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Title: The Science of Fingerprints - Classification and Uses
Author: United States. Federal Bureau of Investigation
Language: English
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THE SCIENCE
OF
FINGERPRINTS
Classification and Uses
UNITED STATES DEPARTMENT OF JUSTICE
FEDERAL BUREAU OF INVESTIGATION
John Edgar Hoover, _Director_
_INTRODUCTION_
the Federal Bureau of Investigation for the use of interested law
enforcement officers and agencies, particularly those which may be
contemplating the inauguration of fingerprint identification files. It
is based on many years' experience in fingerprint identification work
out of which has developed the largest collection of classified
fingerprints in the world. Inasmuch as this publication may serve as a
general reference on classification and other phases of fingerprint
identification work, the systems utilized in the Identification
Division of the Federal Bureau of Investigation are set forth fully.
The problem of pattern interpretation, in particular, is discussed in
detail.
Criminal identification by means of fingerprints is one of the most
potent factors in obtaining the apprehension of fugitives who might
otherwise escape arrest and continue their criminal activities
indefinitely. This type of identification also makes possible an
accurate determination of the number of previous arrests and
convictions which, of course, results in the imposition of more
equitable sentences by the judiciary, inasmuch as the individual who
repeatedly violates the law finds it impossible to pose successfully
as a first, or minor, offender. In addition, this system of
identification enables the prosecutor to present his case in the light
of the offender's previous record. It also provides the probation
officers, parole board, and the Governor with definite information
upon which to base their judgment in dealing with criminals in their
jurisdictions.
From earliest times fingerprinting, because of its peculiar
adaptability to the field, has been associated in the lay mind with
criminal identification to the detriment of the other useful phases of
the science. However, the Civil File of the Identification Division of
the Federal Bureau of Investigation contains three times as many
fingerprints as the Criminal File. These civil fingerprints are an
invaluable aid in identifying amnesia victims, missing persons and
unknown deceased. In the latter category the victims of major
disasters may be quickly and positively identified if their
fingerprints are on file, thus providing a humanitarian benefit not
usually associated with fingerprint records.
The regular contributors who voluntarily submit fingerprints to the
Federal Bureau of Investigation play a most important role in the
drama of identification. Their action expands the size of the
fingerprint files, thereby increasing the value of the files to all
law enforcement agencies. Mutual cooperation and efficiency are
resultant by-products.
The use of fingerprints for identification purposes is based upon
distinctive ridge outlines which appear on the bulbs on the inside of
the end joints of the fingers and thumbs. These ridges have definite
contours and appear in several general pattern types, each with
general and specific variations of the pattern, dependent on the shape
and relationship of the ridges. The outlines of the ridges appear most
clearly when inked impressions are taken upon paper, so that the
ridges are black against a white background. This result is achieved
by the ink adhering to the friction ridges. Impressions may be made
with blood, dirt, grease or any other foreign matter present on the
ridges, or the saline substance emitted by the glands through the
ducts or pores which constitute their outlets. The background or
medium may be paper, glass, porcelain, wood, cloth, wax, putty,
silverware, or any smooth, nonporous material.
Of all the methods of identification, fingerprinting alone has proved
to be both infallible and feasible. Its superiority over the older
methods, such as branding, tattooing, distinctive clothing,
photography, and body measurements (Bertillon system), has been
demonstrated time after time. While many cases of mistaken
identification have occurred through the use of these older systems,
to date the fingerprints of no two individuals have been found to be
identical.
The background and history of the science of fingerprints constitute
an eloquent drama of human lives, of good and of evil. Nothing, I
think, has played a part more exciting than that enacted by the
fascinating loops, whorls, and arches etched on the fingers of a human
being.
[Signature: J. Edgar Hoover]
J. EDGAR HOOVER,
_Director._
_CONTENTS_
_Chapter_ _Page_
I. The Identification Division of the FBI 1
II. Types of Patterns and Their Interpretation 5
III. Questionable Patterns 71
IV. The Classification Formula and Extensions 87
V. Classification of Scarred Patterns--Amputation--Missing at
Birth 98
VI. Filing Sequence 103
VII. Searching and Referencing 109
VIII. How To Take Inked Fingerprints 114
IX. Problems in the Taking of Inked Fingerprints 118
X. Problems and Practices in Fingerprinting the Dead 131
XI. Establishment of a Local Fingerprint Identification Bureau 160
XII. Latent Impressions 173
XIII. Powdering and Lifting Latent Impressions 175
XIV. Chemical Development of Latent Impressions 177
XV. The Use of the Fingerprint Camera 184
XVI. Preparation of Fingerprint Charts for Court Testimony 190
XVII. Unidentified Latent Fingerprint File 194
CHAPTER I
_The Identification Division of the FBI_
The FBI Identification Division was established in 1924 when the
records of the National Bureau of Criminal Investigation and the
Leavenworth Penitentiary Bureau were consolidated in Washington, D.C.
The original collection of only 810,000 fingerprint cards has expanded
into many millions. The establishment of the FBI Identification
Division resulted from the fact that police officials of the Nation
saw the need for a centralized pooling of all fingerprint cards and
all arrest records.
The Federal Bureau of Investigation offers identification service free
of charge for official use to all law enforcement agencies in this
country and to foreign law enforcement agencies which cooperate in the
International Exchange of Identification Data. Through this
centralization of records it is now possible for an officer to have
available a positive source of information relative to the past
activities of an individual in his custody. It is the Bureau's present
policy to give preferred attention to all arrest fingerprint cards
since it is realized that speed is essential in this service.
In order that the FBI Identification Division can provide maximum
service to all law enforcement agencies, it is essential that standard
fingerprint cards and other forms furnished by the FBI be utilized.
Fingerprints must be clear and distinct and complete name and
descriptive data required on the form should be furnished in all
instances. Fingerprints should be submitted promptly since delay might
result in release of a fugitive prior to notification to the law
enforcement agency seeking his apprehension.
When it is known to a law enforcement agency that a subject under
arrest is an employee of the U.S. Government or a member of the Armed
Forces, a notation should be placed in the space for "occupation" on
the front of the fingerprint card. Data such as location of agency or
military post of assignment may be added beside the space reserved for
the photograph on the reverse side of the card.
Many instances have been observed where an individual is fingerprinted
by more than one law enforcement agency for the same arrest. This
duplicate submission of fingerprints can be eliminated by placing a
notation on the first set of fingerprints sent to the FBI requesting
copies of the record for other interested law enforcement agencies,
thereby eliminating submission of fingerprints by the latter agencies.
If a photograph is available at the time fingerprints are submitted to
the FBI Identification Division, it should be identified on the
reverse side with the individual's complete name, name of the
department submitting, the department's number, and it should be
securely pasted in the space provided on the fingerprint card. If a
photograph is to be submitted at a later date, it should be held until
the identification record or "no record" reply from the FBI is
received in order that FBI number or fingerprint classification can be
added to the reverse side of the photograph for assistance of the
Identification Division in relating it to the proper record.
The FBI number, if known, and any request for special handling, such
as collect wire or telephone reply, should be indicated on the
fingerprint card in the appropriate space. Such notations eliminate
the need for an accompanying letter of instructions.
As indicated, the FBI's service is given without cost to regularly
constituted law enforcement agencies and officers. Supplies of
fingerprint cards and self-addressed, franked envelopes will be
forwarded upon the request of any law enforcement officer. The
following types of cards and forms are available: Criminal (Form
FD-249), used for both arrest and institution records; Applicant (Form
FD-258); Personal Identification (Form FD-353); Death Sheet (Form
R-88); Disposition Sheet (Form R-84); Wanted Notice (Form 1-12);
Record of Additional Arrest (Form 1-1). An order form for
identification supplies appears each month with the insert to the FBI
Law Enforcement Bulletin.
In addition to its criminal identification activities, the Bureau's
Identification Division maintains several auxiliary services. Not the
least of these is the system whereby fugitives are identified through
the comparison of fingerprints which are received currently. When a
law enforcement officer desires the apprehension of a fugitive and the
fingerprints of that individual are available, it is necessary only
that he inform the Bureau of this fact so a wanted notice may be
placed in the fugitive's record. This insures immediate notification
when the fugitive's fingerprints are next received.
The fugitive service is amplified by the Bureau's action in
transmitting a monthly bulletin to all law enforcement agencies which
forward fingerprints for its files. In this bulletin are listed the
names, descriptions, and fingerprint classifications of persons wanted
for offenses of a more serious character. This information facilitates
prompt identifications of individuals arrested for any offense or
otherwise located by those receiving the bulletin.
Missing-persons notices are posted in the Identification files so that
any incoming record on the missing person will be noted. Notices are
posted both by fingerprint card and by name, or by name alone if
fingerprints are not available. The full name, date, and place of
birth, complete description and photograph of a missing person should
be forwarded, along with fingerprints, if available. Upon receipt of
pertinent information, the contributing agency is advised immediately.
A section on missing persons is carried as an insert in the Law
Enforcement Bulletin.
The FBI Identification Division has arranged with the identification
bureaus of many foreign countries to exchange criminal identifying
data in cases of mutual interest. Fingerprints and arrest records of
persons arrested in this country are routed to the appropriate foreign
bureaus in cases when the interested agency in the United States has
reason to believe an individual in custody may have a record in or be
wanted by the other nation. Similarly, fingerprints are referred to
the Federal Bureau of Investigation by foreign bureaus when it seems a
record may be disclosed by a search of the Bureau's records. Numerous
identifications, including a number of fugitives, have been effected
in this manner, and it is believed that the complete development of
this project will provide more effective law enforcement throughout
the world. When the facts indicate an individual may have a record in
another country, and the contributor submits an extra set of his
fingerprints, they are transmitted by this Bureau to the proper
authorities.
In very rare cases persons without hands are arrested. A file on
footprints is maintained in the Identification Division on such
individuals.
In view of the fact that many individuals in the underworld are known
only by their nicknames, the Identification Division has for years
maintained a card-index file containing in alphabetical order the
nicknames appearing on fingerprint cards. When requesting a search of
the nickname file, it is desired that all possible descriptive data be
furnished.
The Latent Fingerprint Section handles latent print work. Articles of
evidence submitted by law enforcement agencies are processed for the
development of latent impressions in the Latent Fingerprint Section.
In addition, photographs, negatives, and lifts of latents are
scrutinized for prints of value for identification purposes.
Photographs of the prints of value are always prepared for the FBI's
files and are available for comparisons for an indefinite period.
Should the law enforcement agency desire additional comparisons it
needs only advise the FBI Identification Division, attention Latent
Fingerprint Section, and either name or submit the prints of the new
suspect. It is not necessary to resubmit the evidence. When necessary,
a fingerprint expert will testify in local court as to his findings.
Should a department have any special problems involving the
development or preservation of fingerprints at a crime scene, the
experts are available for suggestions. In connection with the Latent
Fingerprint Section there is maintained a general appearance file of
many confidence game operators. Searches in this file will be made
upon request. In furnishing data on a suspect, the agency should make
sure that complete descriptive data is sent in. Photographs and other
material on individuals who may be identical with those being sought
will be furnished to the interested departments.
During the years many persons have voluntarily submitted their
fingerprints to the Identification Division for possible use in the
case of an emergency. These cards are not filed with the criminal
fingerprints but are maintained separately. Such prints should be
taken on the standard fingerprint form entitled "Personal
Identification" (Form FD-353). No answer is given to Personal
Identification fingerprint cards.
The fingerprint records of the FBI Identification Division are used
liberally not only by police agencies to obtain previous fingerprint
histories and to ascertain whether persons arrested are wanted
elsewhere, but by prosecutors to whom the information from the
Bureau's files may prove to be valuable in connection with the
prosecution of a case. These records are likewise of frequent value to
the judge for his consideration in connection with the imposition of
sentence. Obviously, the ends of justice may be served most equitably
when the past fingerprint record of the person on trial can be made
known to the court, or information may be furnished to the effect that
the defendant is of hitherto unblemished reputation.
It should be emphasized that FBI identification records are for the
_OFFICIAL_ use of law enforcement and governmental agencies and misuse
of such records by disseminating them to unauthorized persons may
result in cancellation of FBI identification services.
CHAPTER II
_Types of Patterns and Their Interpretation_
_Types of patterns_
Fingerprints may be resolved into three large general groups of
patterns, each group bearing the same general characteristics or
family resemblance. The patterns may be further divided into
sub-groups by means of the smaller differences existing between the
patterns in the same general group. These divisions are as follows:
I. ARCH
_a._ Plain arch.
_b._ Tented arch.
II. LOOP
_a._ Radial loop.
_b._ Ulnar loop.
III. WHORL
_a._ Plain whorl.
_b._ Central pocket loop.
_c._ Double loop.
_d._ Accidental whorl.
Illustrations 1 to 10 are examples of the various types of fingerprint
patterns.
[Illustration: 1. Plain arch.]
[Illustration: 2. Tented arch.]
[Illustration: 3. Tented arch.]
[Illustration: 4. Loop.]
[Illustration: 5. Loop.]
[Illustration: 6. Central pocket loop.]
[Illustration: 7. Plain whorl.]
[Illustration: 8. Double loop.]
[Illustration: 9. Double loop.]
[Illustration: 10. Accidental.]
_Interpretation_
Before pattern definition can be understood, it is necessary to
understand the meaning of a few technical terms used in fingerprint
work.
The _pattern area_ is the only part of the finger impression with
which we are concerned in regard to interpretation and classification.
It is present in all patterns, of course, but in many arches and
tented arches it is impossible to define. This is not important,
however, as the only patterns in which we need to define the pattern
area for classification purposes are loops and whorls. In these two
pattern types the pattern area may be defined as follows:
_The pattern area is that part of a loop or whorl in which appear the
cores, deltas, and ridges with which we are concerned in classifying._
_The pattern areas of loops and whorls are enclosed by type lines._
_Type lines may be defined as the two innermost ridges which start
parallel, diverge, and surround or tend to surround the pattern area._
Figure 11 is a typical loop. Lines A and B, which have been emphasized
in this sketch, are the type lines, starting parallel, diverging at
the line C and surrounding the pattern area, which is emphasized in
figure 12 by eliminating all the ridges within the pattern area.
Figures 72 through 101 should be studied for the location of type
lines.
[Illustration: 11]
[Illustration: 12]
[Illustration: 13]
[Illustration: 14]
[Illustration: 15]
[Illustration: 16]
[Illustration: 17]
[Illustration: 18]
Type lines are not always two continuous ridges. In fact, they are
more often found to be broken. When there is a definite break in a
type line, the ridge immediately _outside_ of it is considered as its
continuation, as shown by the emphasized ridges in figure 13.
Sometimes type lines may be very short. Care must be exercised in
their location. Notice the right type line in figure 14.
When locating type lines it is necessary to keep in mind the
distinction between a divergence and a bifurcation (fig. 15).
_A bifurcation is the forking or dividing of one line into two or more
branches._
_A divergence is the spreading apart of two lines which have been
running parallel or nearly parallel._
According to the narrow meaning of the words in fingerprint parlance,
a single ridge may bifurcate, but it may not be said to diverge.
Therefore, with one exception, the two forks of a bifurcation may
never constitute type lines. The exception is when the forks run
parallel after bifurcating and then diverge. In such a case the two
forks become the two innermost ridges required by the definition. In
illustration 16, the ridges marked "A--A" are type lines even though
they proceed from a bifurcation. In figure 17, however, the ridges
A--A are not the type lines because the forks of the bifurcation do
not run parallel with each other. Instead, the ridges marked "T" are
the type lines.
Angles are never formed by a single ridge but by the abutting of one
ridge against another. Therefore, an angular formation cannot be used
as a type line. In figure 18, ridges A and B join at an angle. Ridge B
does not run parallel with ridge D; ridge A does not diverge. Ridges C
and D, therefore, are the type lines.
_Focal points_--Within the pattern areas of loops and whorls are
enclosed the focal points which are used to classify them. These
points are called delta and core.
_The delta is that point on a ridge at or in front of and nearest the
center of the divergence of the type lines._
It may be:
- A bifurcation
- An abrupt ending ridge
- A dot
- A short ridge
- A meeting of two ridges
- A point on the first recurving ridge located nearest to
the center and in front of the divergence of the type lines.
The concept of the delta may perhaps be clarified by further
exposition. Webster furnishes the following definition: "(1) Delta is
the name of the fourth letter of the Greek alphabet (equivalent to
the English D) from the Phoenician name for the corresponding letter.
The Greeks called the alluvial deposit at the mouth of the Nile, from
its shape, the Delta of the Nile. (2) A tract of land shaped like the
letter "delta," especially when the land is alluvial, and enclosed
within two or more mouths of a river, as the Delta of the Ganges, of
the Nile, of the Mississippi" (fig. 19).
When the use of the word "delta" in physical geography is fully
grasped, its fitness as applied in fingerprint work will become
evident. Rivers wear away their banks and carry them along in their
waters in the form of a fine sediment. As the rivers unite with seas
or lakes, the onward sweep of the water is lessened, and the sediment,
becoming comparatively still, sinks to the bottom where there is
formed a shoal which gradually grows, as more and more is
precipitated, until at length a portion of the shoal becomes higher
than the ordinary level of the stream. There is a similarity between
the use of the word "delta" in physical geography and in fingerprints.
The island formed in front of the diverging sides of the banks where
the stream empties at its mouth corresponds to the delta in
fingerprints, which is the first obstruction of any nature at the
point of divergence of the type lines in front of or nearest the
center of the divergence.
[Illustration: 19]
[Illustration: 20]
In figure 20, the dot marked "delta" is considered as the delta
because it is the first ridge or part of a ridge nearest the point of
divergence of the two type lines. If the dot were not present, point B
on ridge C, as shown in the figure, would be considered as the delta.
This would be equally true whether the ridges were connected with one
of the type lines, both type lines, or disconnected altogether. In
figure 20, with the dot as the delta, the first ridge count is ridge
C. If the dot were not present, point B on ridge C would be considered
as the delta and the first count would be ridge D. The lines X--X and
Y--Y are the type lines, not X--A and Y--Z.
In figures 21 to 24, the heavy lines A--A and B--B are type lines with
the delta at point D.
[Illustration: 21]
[Illustration: 22]
[Illustration: 23]
[Illustration: 24]
[Illustration: 25]
[Illustration: 26]
Figure 25 shows ridge A bifurcating from the lower type line inside
the pattern area. Bifurcations are also present within this pattern at
points B and C. The bifurcation at the point marked "delta" is the
only one which fulfills all conditions necessary for its location. It
should be understood that the diverging type lines must be present in
all delta formations and that wherever one of the formations mentioned
in the definition of a delta may be, it must be located midway between
two diverging type lines at or just in front of where they diverge in
order to satisfy the definition and qualify as a delta.
When there is a choice between two or more possible deltas, the
following rules govern:
- _The delta may not be located at a bifurcation which does
not open toward the core._
In figure 26, the bifurcation at E is closer to the core than the
bifurcation at D. However, E is not immediately in front of the
divergence of the type lines and it _does not_ open toward the core.
A--A and B--B are the only possible type lines in this sketch and it
follows, therefore, that the bifurcation at D must be called the
delta. The first ridge count would be ridge C.
- _When there is a choice between a bifurcation and another
type of delta, the bifurcation is selected._
A problem of this type is shown in figure 27. The dot, A, and the
bifurcation are equally close to the divergence of the type lines, but
the bifurcation is selected as the delta. The ridges marked "T" are
the type lines.
[Illustration: 27]
[Illustration: 28]
- _When there are two or more possible deltas which conform
to the definition, the one nearest the core is chosen._
Prints are sometimes found wherein a single ridge enters the pattern
area with two or more bifurcations opening toward the core. Figure 28
is an example of this. Ridge A enters the pattern area and bifurcates
at points X and D. The bifurcation at D, which is the closer to the
core, is the delta and conforms to the rule for deltas. A--A and B--B
are the type lines. A bifurcation which does not conform to the
definition should not be considered as a delta irrespective of its
distance from the core.
- _The delta may not be located in the middle of a ridge
running between the type lines toward the core, but at the
nearer end only._
The location of the delta in this case depends entirely upon the point
of origin of the ridge running between the type lines toward the core.
If the ridge is entirely within the pattern area, the delta is located
at the end nearer the point of divergence of the type lines. Figure 29
is an example of this kind.
[Illustration: 29]
[Illustration: 30]
If the ridge enters the pattern area from a point below the divergence
of the type lines, however, the delta must be located at the end
nearer the core. Ridge A in figure 30 is of this type.
In figure 31, A--A and B--B are the type lines, with the dot as the
delta. The bifurcations cannot be considered as they do not open
toward the core.
[Illustration: 31]
[Illustration: 32]
In figure 32, the dot cannot be the delta because line D cannot be
considered as a type line. It does not run parallel to type line A--A
at any point. The same reason prevents line E from being a type line.
The end of ridge E is the only possible delta as it is a point on the
ridge nearest to the center of divergence of the type lines. The other
type line is, of course, B--B.
The delta is the point from which to start in ridge counting. In the
loop type pattern the ridges intervening between the delta and the
core are counted. The core is the second of the two focal points.
_The core_, as the name implies, is the approximate center of the
finger impression. It will be necessary to concern ourselves with the
core of the loop type only. The following rules govern the selection
of the core of a loop:
- _The core is placed upon or within the innermost
sufficient recurve._
- _When the innermost sufficient recurve contains no ending
ridge or rod rising as high as the shoulders of the loop,
the core is placed on the shoulder of the loop farther from
the delta._
- _When the innermost sufficient recurve contains an uneven
number of rods rising as high as the shoulders, the core is
placed upon the end of the center rod whether it touches the
looping ridge or not._
- _When the innermost sufficient recurve contains an even
number of rods rising as high as the shoulders, the core is
placed upon the end of the farther one of the two center
rods, the two center rods being treated as though they were
connected by a recurving ridge._
_The shoulders of a loop are the points at which the recurving ridge
definitely turns inward or curves._
Figures 33 to 38 reflect the focal points of a series of loops. In
figure 39, there are two rods, but the rod marked "A" does not rise as
high as the shoulder line X, so the core is at B.
[Illustration: 33]
[Illustration: 34]
Figures 40 to 45 illustrate the rule that a recurve must have no
appendage abutting upon it at a right angle between the shoulders and
on the outside. If such an appendage is present between the shoulders
of a loop, that loop is considered spoiled and the next loop outside
will be considered to locate the core. In each of the figures, the
point C indicates the core. Appendages will be further explained in
the section concerning loops.
[Illustration: 35]
[Illustration: 36]
[Illustration: 37]
[Illustration: 38]
[Illustration: 39]
[Illustration: 40]
Figures 46 to 48 reflect interlocking loops at the center, while
figure 49 has two loops side by side at the center. In all these cases
the two loops are considered as one. In figure 46, when the shoulder
line X--X is drawn it is found to cross exactly at the point of
intersection of the two loops. The two loops are considered one, with
one rod, the core being placed at C. In figure 47, the shoulder line
X--X is above the point of intersection of the two loops. The two are
considered as one, with two rods, the core being at C. In figure 48,
the shoulder line X--X is below the point of intersection of the
loops. Again the two are treated as one, with two rods, the core being
placed at C. In figure 49, the two are treated as one, with two rods,
the core being placed at C.
[Illustration: 41]
[Illustration: 42]
[Illustration: 43]
[Illustration: 44]
[Illustration: 45]
[Illustration: 46]
[Illustration: 47]
[Illustration: 48]
[Illustration: 49]
[Illustration: 50]
[Illustration: 51]
[Illustration: 52]
In figure 50, the delta is formed by a bifurcation which is not
connected with either of the type lines. The first ridge count in this
instance is ridge C. If the bifurcation were not present, the delta
would be a point on ridge C and the first ridge count would be ridge
D. In figure 51, the ridge which bifurcates is connected with the
lower type line. The delta in this would be located on the
bifurcation as designated and the first ridge count would be ridge C.
Figure 52 reflects the same type of delta shown in the previous figure
in that the ridge is bifurcating from a type line and then bifurcates
again to form the delta.
_A white space must intervene between the delta and the first ridge
count._ If no such interval exists, the first ridge must be
disregarded. In figures 53 and 54, the first ridge beyond the delta is
counted. In figure 55, it is not counted because there is no interval
between it and the delta. Notice that the ridge running from the delta
toward the core is in a straight line between them. If it were not, of
course, an interval would intervene as in figures 53 and 54.
[Illustration: 53]
[Illustration: 54]
[Illustration: 55]
_The loop_
In fingerprints, as well as in the usual application of the word
"loop," there cannot be a loop unless there is a recurve or turning
back on itself of one or more of the ridges. Other conditions have to
be considered, however. A pattern must possess several requisites
before it may be properly classified as a loop. This type of pattern
is the most numerous of all and constitutes about 65 percent of all
prints.
_A loop is that type of fingerprint pattern in which one or more of
the ridges enter on either side of the impression, recurve, touch or
pass an imaginary line drawn from the delta to the core, and terminate
or tend to terminate on or toward the same side of the impression from
whence such ridge or ridges entered._
_Essentials of a loop_
- A sufficient recurve.
- A delta.
- A ridge count across a looping ridge.
_A sufficient recurve may be defined as that part of a recurving ridge
between the shoulders of a loop. It must be free of any appendages
abutting upon the outside of the recurve at a right angle._
_Appendages_--Some explanation is necessary of the importance attached
to appendages. Much care must be exercised in interpreting appendages
because they sometimes change the shape of the recurving ridge to
which they are connected. For example, a loop with an appendage
abutting upon its recurve between the shoulders and at right angles,
as in illustration 56, will appear sometimes as in illustration 57
with the recurve totally destroyed. For further examples see figures
161 to 184.
[Illustration: 56]
[Illustration: 57]
The same is true of a whorl recurve, as in figures 58 and 59.
It is necessary, therefore, to consider and classify figures 56 and 58
as if they actually appeared as in figures 57 and 59.
In figure 60, there is a ridge marked "A" which enters on one side of
the impression and, after recurving, passes an imaginary line drawn
from the core C to delta D, and terminates on the same side of the
impression from which it entered, marked "B", thus fulfilling all the
conditions required in the definition of a loop. X and Y are the type
lines. It will be noted in figure 61 that there is a ridge which
enters on one side of the impression, recurves, and passes an
imaginary line drawn from the delta to the core. It does not terminate
on the side from which it entered but has a tendency to do so. In this
case, all the requirements of the loop have been met, and consequently
it is classified as such.
[Illustration: 58]
[Illustration: 59]
[Illustration: 60]
Figure 62 shows a ridge entering on one side of the impression,
recurving, and passing beyond an imaginary line drawn from the delta
to the core, although opposite from the pattern shown in figure 61.
After passing the imaginary line, the recurving ridge does not
terminate on the side of the impression from which it entered, but it
has a tendency to do so, and the pattern is, therefore, a loop.
In figure 63, a ridge enters on one side of the impression and then
recurves, containing two rods within it, each of which rises as high
as the shoulder of the loop. From our study of cores, we know that the
top of the rod more distant from the delta is the core, but the
recurving ridge does not pass the imaginary line. For that reason the
pattern is not classified as a loop, but is given the preferential
classification of a tented arch due to the lack of one of the loop
requisites. The proper location of the core and delta is of extreme
importance, for an error in the location of either might cause this
pattern to be classified as a loop.
Figure 64 reflects a similar condition.
[Illustration: 61]
[Illustration: 62]
[Illustration: 63]
[Illustration: 64]
[Illustration: 65]
[Illustration: 66]
In figure 65, there is a looping ridge A which enters on one side of
the impression. The ridges B and C are the type lines. As determined
by rules already stated, the location of the core and the location of
the delta are shown, and if an imaginary line were placed on the core
and delta, the recurving ridge A would cross it. This is another
figure showing a ridge which does not terminate on the side of the
impression from which it entered but tends to do so, and, therefore,
is considered as a loop.
In figure 66, we have a print which is similar in many respects to the
one described in the preceding paragraph, but here the recurving ridge
A continues and tends to terminate on the _opposite_ side of the
impression from which it entered. For this reason the pattern is not a
loop, but a tented arch. The recurving ridge must touch or pass the
imaginary line between delta and core and at least tend to pass out
toward the side from which it entered, so that a ridge count of at
least one can be obtained.
[Illustration: 67]
Figure 67 shows a ridge which enters on one side of the impression
and, after flowing toward the center, turns or loops on itself and
terminates on the same side from whence it entered. This pattern would
be classified as a loop. This pattern should be distinguished from the
pattern appearing in figure 139. Careful study of the pattern in
figure 67 reveals that the core is located at C and the delta D. The
imaginary line between these points will be crossed by the ridge
forming a loop. In figure 139, the core is located on the recurve and
an imaginary line between the delta and the core does not cross a
looping ridge. Figure 139 is thus classified as a tented arch, as will
be seen later.
Figure 68 shows at the center of the print a ridge which forms a
pocket. It will be noticed that ridge A does not begin on the edge of
the print, but this is of no significance. The ridge A within the
pattern area recurves or loops, passing the imaginary line between the
delta and the core, and tends to terminate toward the same side of the
impression from whence it entered. This is a loop pattern possessing
all of the requirements.
In figures 69 and 70, it will be observed that there is a ridge
entering on one side of the pattern which recurves and then turns back
on itself. These patterns are different from any others which have
been shown in this respect but are classified as loops. In each of the
patterns the core and delta are marked "C" and "D". The reader should
trace the type lines in order to ascertain why the delta is located at
point D, and then apply the delta rule.
[Illustration: 68]
[Illustration: 69]
Figure 71 is an example of loops as they appear on the rolled
impression portion of a fingerprint card.
[Illustration: 70]
[Illustration: 71]
Right Hand
--------------------------------------------------------------------------
1. Thumb | 2. Index | 3. Middle | 4. Ring | 5. Little
| finger | finger | finger | finger
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
--------------------------------------------------------------------------
Left Hand
--------------------------------------------------------------------------
6. Thumb | 7. Index | 8. Middle | 9. Ring | 10. Little
| finger | finger | finger | finger
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
--------------------------------------------------------------------------
_Ridge counting_
_The number of ridges intervening between the delta and the core is
known as the ridge count._ The technical employees of the Federal
Bureau of Investigation count each ridge which _crosses or touches_ an
imaginary line drawn from the delta to the core. Neither delta nor
core is counted. A red line upon the reticule of the fingerprint glass
is used to insure absolute accuracy. In the event there is a
bifurcation of a ridge exactly at the point where the imaginary line
would be drawn, two ridges are counted. Where the line crosses an
island, both sides are counted. Fragments and dots are counted as
ridges only if they appear to be as thick and heavy as the other
ridges in the immediate pattern. Variations in inking and pressure
must, of course, be considered.
Figures 72 to 97 and figures 98 to 101 show various loop patterns. The
reader should examine each one carefully in order to study the cores
and deltas and to verify the count which has been placed below each
pattern.
[Illustration: 72. 12 counts.]
[Illustration: 73. 2 counts.]
[Illustration: 74. 16 counts.]
[Illustration: 75. 7 counts.]
[Illustration: 76. 4 counts.]
[Illustration: 77. 7 counts.]
[Illustration: 78. 15 counts.]
[Illustration: 79. 16 counts.]
[Illustration: 80. 9 counts.]
[Illustration: 81. 3 counts.]
[Illustration: 82. 9 counts.]
[Illustration: 83. 20 counts.]
[Illustration: 84. 6 counts.]
[Illustration: 85. 2 counts.]
[Illustration: 86. 8 counts.]
[Illustration: 87. 14 counts.]
[Illustration: 88. 5 counts.]
[Illustration: 89. 12 counts.]
[Illustration: 90. 12 counts.]
[Illustration: 91. 3 counts.]
[Illustration: 92. 16 counts.]
[Illustration: 93. 14 counts.]
[Illustration: 94. 16 counts.]
[Illustration: 95. 18 counts.]
[Illustration: 96. 2 counts.]
[Illustration: 97. 1 count.]
[Illustration: 98. 1 count.]
[Illustration: 99. 2 counts.]
[Illustration: 100. 8 counts.]
[Illustration: 101. 13 counts.]
Figure 102 is a sketch reflecting the various types of ridges which
the classifier will encounter when engaging in counting loop patterns.
In figure 103, the lighter lines are caused by the splitting or
fraying of the ridges. Sometimes ingrained dirt will cause a similar
condition between the ridges. These lines are not considered ridges
and should not be counted.
In figure 104, the dot is not the delta because it is not as thick and
heavy as the other ridges and might not be present if the finger were
not perfectly inked and printed.
When the core is located on a spike which touches the inside of the
innermost recurving ridge, the recurve is included in the ridge count
only when the delta is located below a line drawn at right angles to
the spike.
Figures 105 and 106 are examples of this rule.
If the delta is located in areas A, the recurving ridge is counted.
If the delta is located in areas B, the recurving ridge is not
counted.
[Illustration: 102]
LOOP
25 RIDGE COUNTS
1. SHORT RIDGE
2. }
3. } BIFURCATION
4. }
5. } BIFURCATION
6. RIDGE
7. ENDING RIDGE
8. }
9. } BIFURCATION
10. RIDGE
11. ENDING RIDGE
12. RIDGE
13. SHORT RIDGE
14. }
15. } BIFURCATION
16. }
17. } ISLAND
18. }
19. } BIFURCATION
20. ENDING RIDGE
21. DOT
22. RIDGE
23. }
24. } ISLAND
25. ENDING RIDGE
[Illustration: 103]
[Illustration: 104]
[Illustration: 105]
[Illustration: 106]
_Radial and ulnar loops_
The terms "radial" and "ulnar" are derived from the radius and ulna
bones of the forearm. Loops which flow in the direction of the ulna
bone (toward the little finger) are called ulnar loops and those which
flow in the direction of the radius bone are called radial loops.
For test purposes, fingers of the right hand may be placed on the
corresponding print of the right hand appearing in figure 71, and it
will be noticed that the side of each finger which is nearer to the
thumb on the hand is also nearer to the thumb on the fingerprint card.
Place the fingers of the _left_ hand on the corresponding prints of
the _left_ hand shown in figure 71. It will be noticed that the
arrangement of the prints on the card is the _reverse_ of the
arrangement of the fingers on the hand. _The classification of loops
is based on the way the loops flow on the hand (not the card), so that
on the fingerprint card for the left hand, loops flowing toward the
thumb impression are ulnar, and loops flowing toward the little finger
impression are radial._
_The plain arch_
_In plain arches the ridges enter on one side of the impression and
flow or tend to flow out the other with a rise or wave in the center._
The plain arch is the most simple of all fingerprint patterns, and it
is easily distinguished. Figures 107 to 118 are examples of the plain
arch. It will be noted that there may be various ridge formations such
as ending ridges, bifurcations, dots and islands involved in this type
of pattern, but they all tend to follow the general ridge contour;
i.e., they enter on one side, make a rise or wave in the center, and
flow or tend to flow out the other side.
[Illustration: 107]
[Illustration: 108]
[Illustration: 109]
[Illustration: 110]
Figures 119 and 120 are examples of plain arches which approximate
tented arches. Also, figure 121 is a plain arch approximating a tented
arch as the rising ridge cannot be considered an upthrust because it
is a continuous, and not an ending, ridge. (See following explanation
of the tented arch.)
[Illustration: 111]
[Illustration: 112]
[Illustration: 113]
[Illustration: 114]
[Illustration: 115]
[Illustration: 116]
[Illustration: 117]
[Illustration: 118]
[Illustration: 119]
[Illustration: 120]
[Illustration: 121]
_The tented arch_
In the tented arch, most of the ridges enter upon one side of the
impression and flow or tend to flow out upon the other side, as in the
plain arch type; however, the ridge or ridges at the center do not.
There are three types of tented arches:
- The type in which ridges at the center form a definite
angle; i.e., 90° or less.
- The type in which one or more ridges at the center form an
upthrust. An upthrust is an ending ridge of any length
rising at a sufficient degree from the horizontal plane;
i.e., 45° or more.
- The type approaching the loop type, possessing two of the
basic or essential characteristics of the loop, but lacking
the third.
Figures 122 to 133 are examples of the tented arch.
[Illustration: 122]
[Illustration: 123]
[Illustration: 124]
[Illustration: 125]
[Illustration: 126]
[Illustration: 127]
[Illustration: 128]
[Illustration: 129]
[Illustration: 130]
[Illustration: 131]
[Illustration: 132]
[Illustration: 133]
Figures 122 to 124 are of the type possessing an angle.
Figures 125 to 129 reflect the type possessing an upthrust.
Figures 130 to 133 show the type approaching the loop but lacking one
characteristic.
Tented arches and some forms of the loop are often confused. It should
be remembered by the reader that the _mere converging of two ridges
does not form a recurve, without which there can be no loop_. On the
other hand, there are many patterns which at first sight resemble
tented arches but which on close inspection are found to be loops, as
where one looping ridge will be found in an almost vertical position
within the pattern area, entirely free from and passing in front of
the delta.
Figure 134 is a tented arch. The ridge marked "A--A" in the sketch
enters on one side of the impression and flows to the other with an
acute rise in the center. Ridge C strikes into A at point B and should
not be considered as a bifurcating ridge. The ridges marked "D--D"
would form a tented arch if the rest of the pattern were absent.
[Illustration: 134]
[Illustration: 135]
Figure 135 is a sketch of a pattern reflecting a ridge, A--B, entering
on one side of the impression, recurving, and making its exit on the
other side of the impression. The reader should study this sketch
carefully. It should be borne in mind that there must be a ridge
entering on one side of the impression and recurving in order to make
its exit on the same side from which it entered, or having a tendency
to make its exit on that side, before a pattern can be considered for
possible classification as a loop. This pattern is a tented arch of
the upthrust type. The upthrust is C. There is also an angle at E. D
cannot be termed as a delta, as the ridge to the left of D cannot be
considered a type line because it does not diverge from the ridge to
the right of D but turns and goes in the same direction.
In connection with the types of tented arches, the reader is referred
to the third type. This form of tented arch, the one which approaches
the loop, may have _any combination of two of the three basic loop
characteristics, lacking the third_. These three loop characteristics
are, to repeat:
- _A sufficient recurve._
- _A delta._
- _A ridge count across a looping ridge._
It must be remembered that a recurve must be free of any appendage
abutting upon it at a right angle between the shoulders, and a true
ridge count is obtained only by crossing a looping ridge freely, with
a white space intervening between the delta and the ridge to be
counted.
[Illustration: 136]
[Illustration: 137]
Figures 136 and 137 are tented arches having loop formations within
the pattern area but with deltas upon the loops, by reason of which it
is impossible to secure a ridge count. The type lines run parallel
from the left in figures 136 and 137. These tented arches have two of
the loop characteristics, recurve and delta, but lack the third, the
ridge count.
In figure 138, the reader will note the similarity to the figures 136
and 137. The only difference is that in this figure the type lines are
running parallel from the right. It will be noted from these three
patterns that the spaces between the type lines at their divergence
show nothing which could be considered as delta formations except the
looping ridges. Such patterns are classified as tented arches because
the ridge count necessary for a loop is lacking.
[Illustration: 138]
[Illustration: 139]
[Illustration: 140]
[Illustration: 141]
Figure 139 is an example of a tented arch. In this pattern, if the
looping ridge approached the vertical it could possibly be a one-count
loop. Once studied, however, the pattern presents no real difficulty.
There are no ridges intervening between the delta, which is formed by
a bifurcation, and the core. It will be noted that the core, in this
case, is at the center of the recurve, unlike those loops which are
broadside to the delta and in which the core is placed upon the
shoulder. This pattern has a recurve and a separate delta, but it
still lacks the ridge count necessary to make it a loop.
Figures 140 and 141 are examples of tented arches. These two figures
are similar in many ways. Each of these prints has three abrupt ending
ridges but lacks a recurve; however, in figure 141 a delta is present
in addition to the three abrupt ending ridges. This condition does not
exist in figure 140, where the lower ending ridge is the delta.
When interpreting a pattern consisting of two ending ridges and a
delta but lacking a recurve, do not confuse the ridge count of the
tented arch with that of the ridge count for the loop. The ridge count
of the tented arch is merely a convention of fingerprinting, a fiction
designed to facilitate a scientific classification of tented arches,
and has no connection with a loop. To obtain a true ridge count there
must be a looping ridge which is crossed freely by an imaginary line
drawn between the delta and the core. The ridge count referred to as
such in connection with the tented arches possessing ending ridges and
no recurve is obtained by imagining that the ending ridges are joined
by a recurve only for the purpose of locating the core and obtaining a
ridge count. If this point is secure in the mind of the classifier,
little difficulty will be encountered.
Figures 140 and 141, then, are tented arches because they have two of
the characteristics of a loop, delta and ridge count, but lack the
third, the recurve.
[Illustration: 142]
[Illustration: 143]
Figure 142 is a loop formation connected with the delta but having no
ridge count across a looping ridge. By drawing an imaginary line from
the core, which is at the top of the rod in the center of the pattern,
to the delta, it will be noted that there is no recurving ridge
passing between this rod and the delta; and, therefore, no ridge count
can result. This pattern is classified as a tented arch. There must be
a white space between the delta and the first ridge counted, or it may
not be counted. Figure 143 is also a tented arch because no ridge
count across a looping ridge can be obtained, the bifurcations being
connected to each other and to the loop in a straight line between
delta and core. The looping ridge is not crossed freely. No white
space intervenes between the delta and the loop. These patterns are
tented arches because they possess two of the characteristics of a
loop, a delta and a recurve, but lack the third, a ridge count across
a looping ridge.
Figure 144 is a tented arch combining two of the types. There is an
angle formed by ridge _a_ abutting upon ridge _b_. There are also the
elements of the type approaching a loop, as it has a delta and ridge
count but lacks a recurve.
[Illustration: 144]
[Illustration: 145]
[Illustration: 146]
Figures 145 to 148 are tented arches because of the angles formed by
the abutting ridges at the center of the patterns.
Figure 149 is a tented arch because of the upthrust present at the
center of the pattern. The presence of the slightest upthrust at the
center of the impression is enough to make a pattern a tented arch.
[Illustration: 147]
[Illustration: 148]
[Illustration: 149]
[Illustration: 150]
An upthrust must be an ending ridge. If continuous as in figure 150,
no angle being present, the pattern is classified as a plain arch.
Figures 151 to 153 are plain arches. Figure 154 is a tented arch.
Figure 155 is a plain arch because it is readily seen that the
apparent upthrust A is a continuation of the curving ridge B. Figure
156 is a tented arch because ridge A is an independent upthrust, and
not a continuation of ridge B.
[Illustration: 151]
[Illustration: 152]
[Illustration: 153]
[Illustration: 154]
[Illustration: 155]
[Illustration: 156]
Figures 157 and 158 are plain arches. Figure 158 cannot be said to be
a looping ridge, because by definition a loop must pass out or tend to
pass out upon the side from which it entered. This apparent loop
passes out upon the opposite side and cannot be said to tend to flow
out upon the same side.
[Illustration: 157]
[Illustration: 158]
In figures 159 and 160, there are ending ridges rising at about the
same degree from the horizontal plane.
Figure 159, however, is a plain arch, while 160 is a tented arch. This
differentiation is necessary because, if the first pattern were
printed crookedly upon the fingerprint card so that the ending ridge
was nearer the horizontal plane, there would be no way to ascertain
the true horizontal plane of the pattern (if the fissure of the finger
did not appear). In other words, there would be no means of knowing
that there was sufficient rise to be called an upthrust, so that it is
safe to classify the print as a plain arch only. In figure 160,
however, no matter how it is printed, the presence of a sufficient
rise could always be ascertained because of the space intervening
between the ending ridge and the ridge immediately beneath it, so that
it is safe to classify such a pattern as a tented arch. The test is,
_if the ridges on both sides of the ending ridge follow its direction
or flow trend, the print may be classified as a plain arch. If,
however, the ridges on only one side follow its direction, the print
is a tented arch_.
[Illustration: 159]
[Illustration: 160]
An upthrust, then, must not only be an ending ridge rising at a
sufficient degree from the horizontal plane, but there must also be a
space between the ending ridge and the ridge immediately beneath it.
_This, however, is not necessary for a short upthrust or spike, or any
upthrust which rises perpendicularly._
In connection with the proper classification to be assigned to those
borderline loop-tented arch cases where an appendage or spike is
thrusting out from the recurve, it is necessary to remember that _an
appendage or a spike abutting upon a recurve at right angles in the
space between the shoulders of a loop on the outside is considered to
spoil the recurve_.
If the appending ridge flows off the looping ridge smoothly in such a
way that it forms a bifurcation and not an abutment of two ridges at a
right angle, the recurve is considered as remaining intact. The test
is to trace the looping ridge toward the appendage, and if, when it is
reached, the tracing may be continued as readily upon the appendage as
upon the looping ridge, with no sudden, sharp change of direction, the
recurve is sufficient. Figures 161 to 184 should be studied with this
in mind.
[Illustration: 161. Tented arch.]
[Illustration: 162. Tented arch.]
[Illustration: 163. Tented arch.]
[Illustration: 164. Tented arch.]
[Illustration: 165. Tented arch.]
[Illustration: 166. Tented arch.]
[Illustration: 167. Tented arch.]
[Illustration: 168. Tented arch.]
[Illustration: 169. Loop.]
[Illustration: 170. Loop.]
[Illustration: 171. Loop.]
[Illustration: 172. Loop.]
[Illustration: 173. Loop.]
[Illustration: 174. Loop.]
[Illustration: 175. Loop.]
[Illustration: 176. Tented arch.]
[Illustration: 177. Tented arch.]
[Illustration: 178. Tented arch.]
[Illustration: 179. Loop.]
[Illustration: 180. Loop.]
[Illustration: 181. Loop.]
[Illustration: 182. Loop.]
[Illustration: 183. Loop.]
[Illustration: 184. Loop.]
Figures 185 to 190 show additional examples of tented arches.
[Illustration: 185]
[Illustration: 186]
[Illustration: 187]
[Illustration: 188]
[Illustration: 189]
[Illustration: 190]
The reason that figure 185 is given the classification of a tented
arch is because of the presence of all the loop requirements with the
exception of one, which is the recurve. In this pattern appear three
ending ridges. The lowest ending ridge provides the delta, and the
other two by the convention explained previously, provide the ridge
count. It is a tented arch, then, of the type approaching the loop,
with two of the characteristics, but lacking the third, a recurve.
Figures 186 and 187 are tented arches of the same type. A close
examination of these prints will reveal that when the imaginary line
is drawn between delta and core no ridge count across a looping ridge
can be obtained. It must be remembered that the core of a loop may not
be placed below the shoulder line. Lacking one of the three
characteristics of a loop, these patterns must be classified as tented
arches. When figure 188 is examined, it will be noticed that the
recurve is spoiled by the appendage abutting upon it between the
shoulders at a right angle, so it must also be classified with the
tented arches. In figure 189, the only possible delta must be placed
upon the looping ridge, thus preventing a ridge count although delta
and recurve are present. Figure 190 is assigned the classification of
a tented arch. One of the requirements of a loop type is that the
ridge enters on one side, recurves, and makes its exit on the side
from which it entered. This, of course, makes it necessary that the
ridge pass between the delta and the core. It will be noted from this
figure that although this ridge passes between the delta and the core,
it does not show any tendency to make its exit on the side from which
it entered, and therefore the loop classification is precluded, and it
is a tented arch.
_The whorl_
The patterns to which numerical values are assigned in deriving the
"primary" in the extension of the Henry System of fingerprint
classification used by the Federal Bureau of Investigation are the
whorl-type patterns, which occur in about 30 percent of all
fingerprints.
_The whorl is that type of pattern in which at least two deltas are
present with a recurve in front in each._ Figures 191 to 193 reflect
the minimum requirements for the whorl.
[Illustration: 191]
[Illustration: 192]
[Illustration: 193]
It is important to note that the above definition is very general;
however, this pattern may be subdivided for extension purposes in
large groups where whorls are predominant. Even though this extension
may be used, all types of whorls are grouped together under the
general classification of "Whorl" and are designated by the letter
"W".
The aforementioned subdivisions are as follows: The Plain Whorl, The
Central Pocket Loop, The Double Loop, and The Accidental.
_The plain whorl_
The "plain whorl" consists of the simplest form of whorl construction
and is the most common of the whorl subdivisions. It is designated by
the symbol "W" for both general classification and extension purposes.
_The plain whorl has two deltas and at least one ridge making a
complete circuit, which may be spiral, oval, circular, or any variant
of a circle. An imaginary line drawn between the two deltas must touch
or cross at least one of the recurving ridges within the inner pattern
area. A recurving ridge, however, which has an appendage connected
with it in the line of flow cannot be construed as a circuit. An
appendage connected at that point is considered to spoil the recurve
on that side._
Figures 194 to 211 are typical examples of the plain whorl type.
Figure 212 is, however, a loop, as the circuit is spoiled on one side
by an appendage.
[Illustration: 194]
[Illustration: 195]
[Illustration: 196]
[Illustration: 197]
[Illustration: 198]
[Illustration: 199]
[Illustration: 200]
[Illustration: 201]
[Illustration: 202]
[Illustration: 203]
[Illustration: 204]
[Illustration: 205]
[Illustration: 206]
[Illustration: 207]
[Illustration: 208]
[Illustration: 209]
[Illustration: 210]
[Illustration: 211]
[Illustration: 212]
_Central pocket loop_
Within the whorl group, the subclassification type "central pocket
loop" is used for extension purposes only. In general classification
it is designated by the letter "W". Figures 213 to 236 are central
pocket loops.
_The central pocket loop type of whorl has two deltas and at least one
ridge making a complete circuit, which may be spiral, oval, circular,
or any variant of a circle. An imaginary line drawn between the two
deltas must not touch or cross any of the recurving ridges within the
inner pattern area. A recurving ridge, however, which has an appendage
connected with it in the line of flow and on the delta side cannot be
construed as a circuit. An appendage connected at that point is
considered to spoil the recurve on that side._
_In lieu of a recurve in front of the delta in the inner pattern area,
an obstruction at right angles to the line of flow will suffice._
It is necessary that the inner line of flow be fixed artificially.
_The inner line of flow is determined by drawing an imaginary line
between the inner delta and the center of the innermost recurve or
looping ridge._
In the central pocket loop, one or more of the simple recurves of the
plain loop type usually recurve a second time to form a pocket within
the loop. The second recurve, however, need not be a continuation
of--or even connected with--the first. It may be an independent ridge.
If no second recurve is present, an obstruction at right angles to the
inner line of flow is acceptable in lieu of it. An obstruction may be
either curved or straight. A dot, of course, may not be considered an
obstruction.
_The definition does not require a recurve to cross the line of flow
at right angles. The angle test needs to be applied to obstructions
only._
The recurve or obstruction of the central pocket loop, as that of the
plain whorl, must be free of any appendage connected to it at the
point crossed by the line of flow and on the delta side. An appendage
at that point is considered to spoil the recurve or obstruction.
[Illustration: 213]
[Illustration: 214]
[Illustration: 215]
[Illustration: 216]
[Illustration: 217]
[Illustration: 218]
[Illustration: 219]
[Illustration: 220]
[Illustration: 221]
[Illustration: 222]
[Illustration: 223]
[Illustration: 224]
[Illustration: 225]
[Illustration: 226]
[Illustration: 227]
[Illustration: 228]
[Illustration: 229]
[Illustration: 230]
[Illustration: 231]
[Illustration: 232]
[Illustration: 233]
[Illustration: 234]
[Illustration: 235]
[Illustration: 236]
Figures 237 and 238 are also central pocket loops despite the
appendages connected to the recurves, because they are not connected
at the point crossed by the line of flow.
Figure 239, although possessing a recurve, is classified as a loop
because the second delta is located on the only recurving ridge.
[Illustration: 237]
[Illustration: 238]
[Illustration: 239]
[Illustration: 240]
[Illustration: 241]
[Illustration: 242]
Figures 240 to 244, although possessing one delta and a delta
formation, are classified as loops because the obstructions do not
cross the line of flow at right angles.
[Illustration: 243]
[Illustration: 244]
[Illustration: 245]
[Illustration: 246]
[Illustration: 247]
[Illustration: 248]
Figures 245 to 254 have two deltas and one or more recurves, but they
are classified as loops because each recurve is spoiled by an
appendage connected to it at the point crossed by the line of flow.
[Illustration: 249]
[Illustration: 250]
[Illustration: 251]
[Illustration: 252]
[Illustration: 253]
[Illustration: 254]
_Double loop_
Within the whorl group, the subclassification type "double loop" is
used for extension purposes only. In general classification it is
designated by the letter "W".
_The double loop consists of two separate loop formations, with two
separate and distinct sets of shoulders, and two deltas._
The word "separate," as used here, does not mean unconnected. The two
loops may be connected by an appending ridge provided that it does not
abut at right angles between the shoulders of the loop formation. The
appendage rule for the loop applies also to the double loop. An
appendage abutting upon a loop at right angles between the shoulders
is considered to spoil the loop, while an appendage which flows off
smoothly is considered to leave the recurve intact.
The fact that there must be two separate loop formations eliminates
from consideration as a double loop the "S" type core, the
interlocking type core, and the formation with one loop inside
another.
The loops of a double loop do not have to conform to the requirements
of the loop. In other words, no ridge count is necessary.
It is not essential that both sides of a loop be of equal length, nor
that the two loops be of the same size. Neither is it material from
which side the loops enter.
The distinction between twinned loops and lateral pocket loops made by
Henry and adopted by other authors has been abandoned by the Federal
Bureau of Investigation because of the difficulty in locating and
tracing the loops. Both types have been consolidated under the
classification "double loop."
Figures 255 to 266 are double loops.
[Illustration: 255]
[Illustration: 256]
[Illustration: 257]
[Illustration: 258]
[Illustration: 259]
[Illustration: 260]
[Illustration: 261]
[Illustration: 262]
[Illustration: 263]
[Illustration: 264]
[Illustration: 265]
[Illustration: 266]
Figure 267 is a plain whorl. It is not classified as a double loop as
one side of one loop forms the side of the other. Figure 268 is a
plain loop. It is not a double loop because all of the recurves of the
loop on the right are spoiled by appendages.
[Illustration: 267]
[Illustration: 268]
_Accidental_
Within the whorl group the subdivision type "accidental" is used for
extension purposes only. In general classification it is designated by
the letter "W" and for extension purposes by the letter "X".
_The accidental whorl is a pattern consisting of a combination of two
different types of pattern, with the exception of the plain arch, with
two or more deltas; or a pattern which possesses some of the
requirements for two or more different types; or a pattern which
conforms to none of the definitions._ It may be a combination of loop
and tented arch, loop and whorl, loop and central pocket loop, double
loop and central pocket loop, or other such combinations. The plain
arch is excluded as it is rather the absence of pattern than a
pattern. Underneath every pattern there are ridges running from one
side to the other, so that if it were not excluded every pattern but
the plain arch would be an accidental whorl.
This subclassification also includes those exceedingly unusual
patterns which may not be placed by definition into any other classes.
Figures 269 to 271 are accidentals combining a loop with a tented
arch. Figures 272 to 276 combine a loop and a plain whorl or central
pocket loop. Figure 277 combines a loop and a double loop. Figure 278
combines a loop and a plain arch, so it is classified as a loop.
Figure 279 combines a loop and a tented arch.
[Illustration: 269]
[Illustration: 270]
[Illustration: 271]
[Illustration: 272]
[Illustration: 273]
[Illustration: 274]
[Illustration: 275]
[Illustration: 276]
[Illustration: 277]
Some whorls may be found which contain ridges conforming to more than
one of the whorl subdivisions described. In such cases, the order of
preference (if any practical distinction need be made) should be: (1)
accidental, (2) double loop, (3) central pocket loop, (4) plain whorl.
[Illustration: 278]
[Illustration: 279]
[Illustration: 280]
[Illustration: 281]
_Whorl tracing_
The technique of whorl tracing depends upon the establishment of the
focal points--the deltas. Every whorl has two or more. When the deltas
have been located, the ridge emanating from the lower side or point of
the extreme left delta is traced until the point nearest or opposite
the extreme right delta is reached. The number of ridges intervening
between the tracing ridge and the right delta are then counted. If the
ridge traced passes inside of (above) the right delta, and three or
more ridges intervene between the tracing ridge and the delta, the
tracing is designated as an "inner"--I (fig. 280). If the ridge traced
passes outside (below) the right delta, and three or more ridges
intervene between the tracing ridge and the right delta, the tracing
is designated as an "outer"--O (fig. 281). All other tracings are
designated as "meeting"--M (figs. 282 to 287).
[Illustration: 282]
[Illustration: 283]
[Illustration: 284]
[Illustration: 285]
[Illustration: 286]
[Illustration: 287]
Tracing begins from the left delta. In no instance is a tracing to
begin on a type line. In figure 288, tracing begins at the short ridge
which is the left delta. It is true that inasmuch as the short ridge
ends immediately the type line is next followed, but this is only
because the type line is the next lower ridge. Its status as a type
line is independent and has no bearing on the fact that it is being
traced. This point is illustrated further in figure 289. This pattern
shows an inner tracing. It will be noted that the delta is at the
point on the first recurve nearest to the center of the divergence of
the type lines. It will be further noted that tracing begins at the
point of delta on the left and continues toward the right, passing
inside of the right delta, with three ridges intervening between the
tracing ridge and the right delta. This shows the tracing to be an
inner tracing. If, in this case, the type line were traced (which
would be the incorrect procedure), only two ridges would intervene
between the tracing ridge and the right delta, resulting in an
erroneous meeting tracing. Figure 290 is another example of the
application of this rule. This illustration is also an inner whorl.
When the ridge traced ends abruptly, and it is determined that the
ridge definitely ends, the tracing drops down to the point on the next
lower ridge immediately beneath the point where the ridge above ends,
continuing from there. Figure 291, therefore, is an outer whorl.
[Illustration: 288]
[Illustration: 289]
In this connection it should be noted that the rule for dropping to
the next lower line applies only when the ridge _definitely_ ends.
Short breaks in a ridge which may be due to improper inking, the
presence of foreign matter on the ridges, enlarged pores, disease, or
worn ridges should not be considered as definite ridge endings. The
determination of what constitutes a definite ending will depend, of
course, upon the good judgment of the classifier. When the question
arises as to whether a break encountered in the ridge tracing is a
definite ending, or whether there has been interference with a natural
impression, the whole pattern should be examined to ascertain whether
such breaks are general throughout the pattern. If they are found to
be common, consideration should then be given to the possibility that
the break is not a definite ridge ending. Appropriate reference
tracing should be done in all such cases.
[Illustration: 290]
[Illustration: 291]
Whenever the ridge traced bifurcates, the rule for tracing requires
that the lower limb or branch proceeding from the bifurcation be
followed. This is illustrated in 292.
[Illustration: 292]
Accidentals often possess three or more deltas. In tracing them only
the extreme deltas are considered, the tracing beginning at the
extreme left delta and proceeding toward the extreme right delta, as
illustrated in figure 293.
In a double loop or accidental the problem of where to stop tracing is
sometimes presented. The rule is, _when the tracing passes inside of
the right delta, stop at the nearest point to the right delta on the
upward trend_, as in figure 294. If no upward trend is present,
continue tracing until a point opposite the right delta, or the delta
itself, is reached (figs. 295 and 296).
[Illustration: 293]
[Illustration: 294]
[Illustration: 295]
[Illustration: 296]
CHAPTER III
_Questionable Patterns_
No matter how definite fingerprint rules and pattern definitions are
made, there will always be patterns concerning which there is doubt as
to the classification they should be given. The primary reason for
this is the fact that probably no two fingerprints will ever appear
which are exactly alike. Other reasons are differences in the degree
of judgment and interpretation of the individual classifying
fingerprints, the difference in the amount of pressure used by the
person taking the prints, and the amount or kind of ink used. Nothing
can be done about faulty inking or pressure once the prints are taken.
The patterns which are questionable merely because they seem to have
characteristics of two or more types can be classified by strict
adherence to the definitions in deducing a preference. The following
section is devoted to such patterns with an explanation of each.
[Illustration: 297]
[Illustration: 298]
Figure 297 has two loop formations. The one on the left, however, has
an appendage abutting upon the shoulders of its recurve at a right
angle. The left portion of the impression, therefore, is of the tented
arch type. The combination of two different types of patterns would be
classified in the whorl group (accidental), but this impression has
only the one delta. The right portion of the pattern detail contains a
true loop which fulfills all the loop requirements, i.e., a sufficient
recurve, a delta, and a ridge count across a looping ridge. In the
choice existing between a tented arch and a loop, preference is given
to the loop classification and this impression would be classified as
a loop.
[Illustration: 299]
[Illustration: 300]
[Illustration: 301]
[Illustration: 302]
Figure 298, at a glance, seems to fulfill the requirements of a whorl
(two deltas and a ridge making a complete circuit). The part of the
circuit in front of the right delta, however, cannot be construed as a
recurving ridge because of the appendage abutting upon it in the line
of flow. This pattern, therefore, is a one-count loop.
Figure 299 is a very difficult and unusual pattern. It has
characteristics of three types, the whorl, the loop, and the tented
arch. It is given the preference of an accidental type of whorl (loop
over a tented arch). This pattern should be referenced both as a loop
and as a tented arch.
Figure 300 is shown for the purpose of explaining that in the whorl,
as this print is, appendages at the top of the recurve will not spoil
or affect the recurve. Hence, the impression is a good whorl of the
central pocket loop type and needs no reference.
Figure 301 is classified as a whorl of the double loop type. There are
present two distinct loops and two deltas (the right delta is not
present as the impression was not rolled sufficiently). The pattern is
unusual because the loops are side by side and flowing in the same
direction. The tracing is an inner tracing.
Figure 302 should present no difficulty. It is classified as a plain
arch for its ridge construction follows the rule of a plain arch,
i.e., "enter one side and flow or tend to flow to the other."
Figure 303 is a plain arch. The dot at the center is not elongated
enough to be considered an upthrust. A dot, even though as thick and
heavy as the surrounding ridges, is not considered for any purpose but
ridge counting or fixing a delta.
Figure 304 is a pattern somewhat similar to the previous illustration.
As indicated before, dots are considered as ridges only in ridge
counting and fixing a delta. This pattern, therefore, must be
classified as a plain arch, rather than a tented arch with two ending
ridges and a delta formation.
Figure 305, although showing an appendage upon each recurve on the
left side, is classified as a whorl of the central pocket loop type,
with two deltas and a recurve in front of each. To spoil the recurve
of a whorl the appendage must be connected to the recurve at the point
of contact with the line of flow.
[Illustration: 303]
[Illustration: 304]
[Illustration: 305]
[Illustration: 306]
In figure 306, the impression has two equally good loop formations. As
it has but one delta, it cannot be classified as a whorl of the double
loop type nor as a loop since it would be difficult to make a
preferential choice between the two looping ridges. It is arbitrarily
given the classification of a tented arch.
In figure 307, the difficulty lies in locating the delta. The only
ridges answering the definition of type lines (ridges running parallel
and then diverging to enclose the pattern area) have three ending
ridges between them. The type lines, the delta, and the core are
located as indicated. The pattern is classified as a six-count loop.
Figure 308 is classified as a tented arch, although it appears at
first glance to be a loop. Closer inspection shows that the looping
ridge does not tend to go out the side from which it entered but
rather seems to proceed downward ending in an abutment forming a
definite angle of 90°.
[Illustration: 307]
[Illustration: 308]
[Illustration: 309]
[Illustration: 310]
[Illustration: 311]
In figure 309, an impression is shown which at first appears to be a
loop. Closer inspection will show that one of the elements of the loop
type is missing, namely, a ridge count across a looping ridge; for it
is to be borne in mind that the recurve of the innermost loop should
be free of appendages abutting between the shoulders at right angles.
The core, in this illustration, therefore, is placed where the
appendage of the innermost loop touches the next ridge which is a good
recurve. If an imaginary line is placed between delta and core, it
will be seen that there are no intervening ridges; hence, there is no
ridge count.
Figure 310 is a pattern which contains two elements of a loop but
lacks the third. It is classified as a tented arch. Thus an impression
having a delta and a recurve, but not having a ridge count across a
looping ridge, falls into this classification.
It will be noticed that although this pattern has the resemblance of a
plain arch, the center of the impression actually contains a partially
formed loop. A recurving ridge enters from the right side and exits in
the same direction. A delta also appears just below the recurve. In
attempting to obtain a ridge count, it is seen that the imaginary
line drawn between the delta and the core runs directly along the
ridge emanating from the former and which is joined onto the side of
the recurving ridge. For this reason, no ridge count is possible.
[Illustration: 312]
Figure 311 is a tented arch. There are three loop formations, each one
of which is spoiled by an appendage abutting upon its recurve between
the shoulders at a right angle. It cannot be classified as an
accidental as the patterns are all of the same type, i.e., tented
arches. An accidental type of whorl is a combination of two or more
_different_ types of patterns exclusive of the plain arch.
Figure 312 is a loop. It cannot be classified as a whorl of the double
loop type because the formation above the lower loop is too pointed
and it also has an appendage abutting upon it at a right angle.
Figure 313 at first glance appears to be a whorl of the double loop
type. Upon closer inspection, however, it will be noticed that there
are no delta formations other than on the recurves. There are, then,
two tented arch formations. As two patterns of the same type cannot
form an accidental whorl, the impression must be classified as a
tented arch.
[Illustration: 313]
[Illustration: 314]
Figure 314 is an accidental whorl, combining a loop and a tented arch.
The tented arch is directly beneath the innermost loop, and is of the
upthrust type.
Figure 315 consists of a loop over a dot with an apparent second
delta. This pattern must be classified as a loop, as a dot may not be
considered an upthrust unless elongated vertically.
[Illustration: 315]
[Illustration: 316]
[Illustration: 317]
Even though a dot may be as thick and heavy as the surrounding ridges,
it may be considered only in ridge counting or fixing a delta.
Figure 316 at first glance appears to be an accidental whorl, but on
closer inspection it proves to be a loop. Although there are three
delta formations present, it should be observed that recurving ridges
appear in front of only one (D-1).
Figure 317 has the general appearance of a loop. The looping ridge A,
at the center, has an appendage B abutting upon its recurve. The
abutment is at right angles and therefore spoils the recurve. The
pattern is a tented arch.
Figure 318 is a tented arch which approaches both the loop and the
whorl type patterns. It cannot be considered a whorl, however, as the
recurve on the left is spoiled by an appendage (figs. 58 and 59). Nor
can it be a loop because there is no ridge count across a looping
ridge. The pattern, then, is a tented arch of the type possessing two
of the basic characteristics of the loop and lacking the third. The
delta and the sufficient recurve are present but the ridge count is
missing.
Figure 319 seems at first glance to be a double loop. It will be
noted, however, that the inner delta formation would be located upon
the only looping ridge of the upper loop formation. Since the delta
would be located on the only recurve, this recurving ridge is
eliminated from consideration. The pattern is classified as a loop.
Figure 320 is a loop of two counts, with the delta at B. There is a
ridge making a complete circuit present, but point A cannot be used as
a delta because it answers the definition of a type line. It should be
considered a delta only if it presented an angular formation. Placing
the delta upon the recurve would spoil that recurve.
[Illustration: 318]
[Illustration: 319]
Figure 321 shows two separate looping ridge formations appearing side
by side and upon the same side of the delta. The core in such case is
placed upon the nearer shoulder of the farther looping ridge from the
delta, the two looping ridges being considered as one loop with two
rods rising as high as the shoulder. The ridge count would be four
(fig. 49).
Figure 322 is an accidental whorl. It is classified thus because it
contains elements of three different patterns, the loop, the double
loop, and the accidental. In such case the order of preference
governs. The delta at the left is point A. The delta at the right is
point C. This point becomes the delta since it is the point nearest
the center of the divergence of the type lines. Point B is eliminated
from consideration as a delta since type lines may not proceed from a
bifurcation unless they flow parallel after the bifurcation and before
diverging.
[Illustration: 320]
[Illustration: 321]
[Illustration: 322]
Figure 323 is a loop. There are two delta formations but the dots
cannot be considered as obstructions crossing the line of flow at
right angles. This precludes the classification of the central pocket
loop type of whorl.
Figure 324 is a loop, the two recurving ridges have appendages and are
considered spoiled. The pattern cannot, therefore, be a whorl even
though two delta formations are present.
[Illustration: 323]
[Illustration: 324]
Figure 325 is classified as a tented arch. If examined closely the
pattern will be seen to have an appendage abutting at a right angle
between the shoulders of each possible recurve. Thus no sufficient
recurve is present.
Figure 326 is a plain arch. There is present no angle which approaches
a right angle. Points A, B, and X are merely bifurcations rather than
an abutment of two ridges at an angle.
[Illustration: 325]
[Illustration: 326]
Figure 327 is a tented arch, not because of the dot, however, as it
cannot be considered an upthrust. The tented arch is formed by the
angle made when the curving ridge above the dot abuts upon the ridge
immediately under and to the left of the dot.
[Illustration: 327]
[Illustration: 328]
Figure 328 consists of two separate looping ridge formations in
juxtaposition upon the same side of a common delta. This pattern
cannot be called a double loop as there is no second delta formation.
In order to locate the core, the two looping ridges should be treated
as one loop with two rods in the center. The core is thus placed on
the far rod (actually on the left shoulder of the far loop), resulting
in a ridge count of four (fig. 49).
[Illustration: 329]
[Illustration: 330]
Figure 329 is a loop of three counts. It cannot be classified as a
whorl as the only recurve is spoiled by the appendage abutting upon it
at the point of contact with the line of flow.
Figure 330 is a plain arch as there is no upthrust (an upthrust must
be an ending ridge), no backward looping turn, and no two ridges
abutting upon each other at a sufficient angle.
Figure 331 is a plain arch. The ending ridge at the center does not
rise at a sufficient angle to be considered an upthrust, and it does
not quite meet the ridge toward which it is flowing and therefore
forms no angle.
Figure 332 is a plain arch. There are two ending ridges, but no
separate delta formation is present.
[Illustration: 331]
[Illustration: 332]
[Illustration: 333]
[Illustration: 334]
Figure 333 is a plain arch. The rising ridge at the center is curved
at the top forming no angle, and does not constitute an upthrust
because it is not an ending ridge.
Figure 334 is a whorl of the double loop type. Two loops and two
deltas are present. It is unusual because the loops are juxtaposed
instead of one flowing over the other, and one delta is almost
directly over the other. The tracing is a meeting tracing.
Figure 335 is a tented arch. Although there is a looping ridge, no
ridge count can be obtained. The core is placed upon the end of the
ridge abutting upon the inside of the loop, and so the imaginary line
crosses no looping ridge, which is necessary.
Figure 336 is a plain arch. The ending ridge at the center cannot be
considered an upthrust because it does not deviate from the general
direction of flow of the ridges on either side. No angle is present as
the ending ridge does not abut upon the curving ridge which envelopes
it.
[Illustration: 335]
[Illustration: 336]
[Illustration: 337]
[Illustration: 338]
[Illustration: 339]
Figure 337 is a plain arch because the dot cannot be considered a
delta as it is not as thick and heavy as the surrounding ridges.
Figure 338 is a tented arch consisting of two ending ridges and a
delta. The short ending ridge is considered a ridge because it is
slightly elongated and not a mere dot.
In figure 339, the only question involved is where to stop tracing.
The rule is: _when tracing on a ridge with an upward trend, stop at
the point on the upward trend which is nearest to the right delta_. X
is the point in this pattern.
In figure 340, the question involved is also one of tracing. In this
pattern, the tracing is not on a ridge with an upward trend. The
tracing, therefore, is continued until a point nearest to the right
delta, or the right delta itself, is reached. This tracing is a
meeting tracing.
[Illustration: 340]
There are a few constantly recurring patterns which, though not
questionable or doubtful as they appear, present a peculiarly
difficult problem in classifying. The patterns referred to are usually
double loops, though accidental whorls and loops sometimes present the
same problems. The difficulty arises when a loop is so elongated that
the recurve does not appear until near the edge of a fully rolled
impression or an impression that is rolled unusually far, as in
figures 341 to 344.
[Illustration: 341]
[Illustration: 342]
[Illustration: 343]
[Illustration: 344]
Figure 341, if classified as it appears, would be an accidental whorl.
Figures 342 and 343 would be double loops, and illustration 344, a
loop. It will be observed that these prints are rolled more fully than
normal. If, however, the next time the prints are taken, they are not
rolled quite so far, the patterns would require a very different
classification, and would show no indication of any need for
referencing to their true classification. The result would be a
failure to establish an identification with the original prints. The
only way in which such an error may be avoided is to classify such
impressions as they would appear if not so fully rolled, and to
conduct a reference search in the classification which would be given
to the prints when rolled to the fullest extent. Applying this rule,
illustration 341 is a tented arch, referenced to a whorl. Figures 342
and 343 are loops, referenced to whorls. Figure 344 is a plain arch,
referenced to a loop.
No set rule can possibly be devised to enable a classifier to know
with certainty where to draw the line when it is doubtful which
classification should be given such a print. Individual judgment is
the only standard. The test is: _if the pattern, in the opinion of the
classifier, is rolled to only a normal width, it should be classified
as it appears. If it seems to be rolled to a width beyond the normal
degree, it should be classified as if rolled only to the normal
degree_. Age, weight, size of fingers (as seen in the plain
impressions), heaviness of the ridges, and experience of the
technician in taking fingerprints are all factors in arriving at the
correct conclusion. The necessity for exercising the utmost care in
dealing with this type of pattern cannot be too highly emphasized.
[Illustration: 345]
[Illustration: 346]
The patterns in figures 345 and 346 also have a second loop near the
edge of the impression. In these two patterns, however, the second
loop is very near the delta and consequently will almost invariably
appear even though not rolled to the fullest extent. The foregoing
rule is not applied to this type of impression. Both are classified as
a whorl and referenced to a loop to take care of the rare contingency
of nonappearance.
CHAPTER IV
_The Classification Formula and Extensions_
_The classification formula_
At this point it is necessary to mention that when prints are
classified, markings are indicated at the bottom of each finger block
to reflect the type. The following symbols are used:
- Under the index fingers the appropriate capital letters
should be placed for every pattern except the ulnar loop.
- Under all other fingers, the appropriate small letter
should be placed for every pattern except the ulnar loop and
the whorl as follows:
Arch a
Tented Arch t
Radial Loop r
- Ulnar loops in any finger are designated by a diagonal
line slanting in the direction of the loop.
- Whorls in any finger are designated by the letter "W". The
classification formula may be composed of the following
divisions:
1. Primary
2. Secondary
3. Subsecondary
4. Major
5. Final
6. Key
The positions in the classification line for these divisions when
completely applied are as illustrated:
Key Major Primary Secondary Subsecondary Final
--------------------------------------------------------------------------
Divisions Classification Classification Classification
20 M 1 U IOI 10
--------------------------------------------------------------------------
L 1 U IOI
Second subsecondary
classification
Key Major Primary Secondary Subsecondary Final
--------------------------------------------------------------------------
Divisions Classification Classification Classification
SLM
---
MMS
4 O 5 U IOI 10
--------------------------------------------------------------------------
I 17 U IOI
THE PRIMARY CLASSIFICATION: For the purpose of obtaining the primary
classification, numerical values are assigned to each of the ten
finger spaces as shown in figure 347. Wherever a whorl appears it
assumes the value of the space in which it is found. Spaces in which
types of patterns other than whorls are present are disregarded in
computing the primary.
The values are assigned as follows:
Fingers No. 1 and No. 2 16
Fingers No. 3 and No. 4 8
Fingers No. 5 and No. 6 4
Fingers No. 7 and No. 8 2
Fingers No. 9 and No. 10 1
[Illustration: 347]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| |
-----------------------------|-------------|
SCARS AND MARKS |PLACE OF |
|BIRTH | 29
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | 19
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT LITTLE
| | MIDDLE | |
|N 16| |N 8|
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
D 16| |D 8| |D 4
---------------------------------------------------------------------------
W | W | \ | W | \
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT |4. LEFT RING |5. LEFT LITTLE
N 4| | MIDDLE | |
| |N 2| |N 1
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
|D 2| |D 1|
---------------------------------------------------------------------------
W | W | / | / | /
---------------------------------------------------------------------------
In figure 347, it will be observed that the odd fingers (Nos. 1, 3, 5,
7, 9) contain the letter D, and the even fingers (Nos. 2, 4, 6, 8, 10)
contain the letter N. The D indicates that the values of these fingers
relate to the denominator, the N that they relate to the numerator.
The summation of the numerical values of the whorl type patterns, if
any, appearing in fingers 1, 3, 5, 7, 9, plus one, is the denominator
of the primary. The summation of the values of the whorls, if any, in
fingers 2, 4, 6, 8, 10, plus one, is the numerator of the primary.
Where no whorl appears in a set of impressions, the primary,
therefore, would be 1 over 1. The 1 that is assigned to the numerator
and the denominator when no whorls appear is also added, for
consistency, to the value of the whorls when they do appear. It will
be understood why it was originally assigned to the no-whorl group
when it is considered how easily a zero might be confused with an O,
which is the symbol used for an outer whorl tracing.
To obtain the primary for the prints in figure 347, the number of
whorls appearing in the odd fingers is ascertained to be 2. Their
positions are noted (1 in No. 1 and 1 in No. 7) and the values
assigned to whorls appearing in those fingers are added together (16
plus 2 = 18). To this sum the arbitrary 1 is added, giving us the
total of 19, which constitutes the denominator for this set of prints.
To get the numerator, it is ascertained that there are 3 whorls
appearing in the even fingers (2, 4 and 6), the values of which are
added together (16 plus 8 plus 4 = 28). To this sum the 1 is added,
giving a numerator of 29, and a complete primary of 29 over 19.
By the word "whorl" is meant all types of whorls, including plain
whorls, central pocket loops, double loops and accidentals. The
tracing of the whorl does not enter into the determination of the
primary.
The method of obtaining the primary can probably be shown best by
illustrations. For example, assume that there is a whorl in the right
index finger only. The value of a whorl in this finger is 16. When 1
over 1 is added the resulting primary is 17 over 1. If a whorl appears
in the right thumb and right index finger, the value is 16 over 16
plus 1 over 1 giving a primary of 17 over 17. If whorls appear in both
index fingers, the value is 16 over 2 plus 1 over 1 giving a primary
of 17 over 3. When whorls appear in both thumbs and both index
fingers, the primary is 21 over 19 and is obtained by the addition 16
plus 4 plus 1 over 16 plus 2 plus 1. If whorls appear in all 10
fingers, the primary is 32 over 32 (16 plus 8 plus 4 plus 2 plus 1
plus 1 over 16 plus 8 plus 4 plus 2 plus 1 plus 1). It will be noted
that the primary classifications extend from 1 over 1 in the no-whorl
group to 32 over 32 in the all-whorl group, providing 1,024 possible
combinations. This does not mean that there are 1,024 even
subdivisions of prints according to these primaries. Just as there is
a preponderance of loops when the types of patterns are considered,
there is also a preponderance of certain primaries, notably: the 1
over 1 primary, or no-whorl group; the 17 denominator; the 19
denominator; the 28 denominator, of which the 31 over 28 group is the
largest; and the 32 denominator, including 2 large primary groups
namely, 31 over 32 and 32 over 32. As a matter of fact, the 1 over 1
group, as a whole, contains over 25 percent of the total number of
prints filed in the FBI. On the other hand, there are a number of
primaries which rarely appear. It follows, therefore, that when a
print is classified in one of these larger groups it is necessary to
complete the classification to a greater extent than is necessary in
the more unusual primaries, so that the group to be searched is small
enough for convenience.
In connection with the counting of whorl values to obtain the primary,
it might be noted that when the whorls outnumber the other patterns
more speed can be achieved by counting those patterns and subtracting
rather than by adding the whorls. This procedure should not be
followed until enough experience is acquired so that it may be noted
at a glance where whorls are not present.
The experienced classifier can tell in what fingers whorls are present
by a glance at a primary classification. For example, a primary of 5
over 17 could mean that there are whorls in the thumbs only.
[Illustration: 348]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| |
-----------------------------|-------------|
SCARS AND MARKS |PLACE OF |
|BIRTH | 9 R
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | 2 R
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT LITTLE
| | MIDDLE | |
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
\ | R | \ | W | \
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT M|4. LEFT RING |5. LEFT LITTLE
18| 10| MIDDLE I| I| 13
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
/ | R | / | W | /
---------------------------------------------------------------------------
THE SECONDARY CLASSIFICATION: After the primary classification, the
fingerprints are subdivided further by using a secondary
classification. Before going into detail, it should be noted that
after the primary is obtained the entire remaining portion of the
classification formula is based upon the arrangement of the
impressions appearing in the right hand as the numerator over the
impressions appearing in the left hand as the denominator. The
arrangement of the even over the uneven fingers is discarded after the
primary is obtained. The secondary classification appears just to the
right of the fractional numerals which represent the primary. It is
shown in the formula by capital letters representing the basic types
of patterns appearing in the index fingers of each hand, that of the
right hand being the numerator and that of the left hand being the
denominator (fig. 348). There are five basic types of patterns which
can appear.
1. Arch A
2. Tented Arch T
3. Radial Loop R
4. Ulnar Loop U
5. Whorl W
[Illustration: 349]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| |
-----------------------------|-------------|
SCARS AND MARKS |PLACE OF |
|BIRTH | 1 R
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | 1 aU
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT LITTLE
| | MIDDLE | |
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
\ | R | \ | \ | \
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT M|4. LEFT RING |5. LEFT LITTLE
18| 10| MIDDLE I| I| 13
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
a | / | / | / | /
---------------------------------------------------------------------------
SECONDARY CLASSIFICATION (SMALL-LETTER GROUP): Prints with an arch or
tented arch in any finger or a radial loop in any except the index
fingers constitute the small-letter group of the secondary
classification. Such "small letters," with the exception of those
appearing in the index fingers, are brought up into the classification
formula in their proper relative positions immediately adjacent to the
index fingers (fig. 349). A dash is used to indicate the absence of
each small letter between the index fingers and another small letter
or between two small letters, as
1 aUa-t 1 aU-t.
------- and ------
1 R-a 1 U-a
Thus, if a radial loop appears in the right thumb, the small letter
"r" would be brought up in the numerator column of the classification
formula and placed just to the left of the capital letter representing
the index finger. Similarly, if an arch or tented arch or a radial
loop would appear in the middle, ring, or little finger of the hand,
the small letter representing such a pattern would be placed on the
classification line to the right of the secondary in the numerator
column if the letter is present in the right hand, and in the
denominator column if in the left hand. When two or more small letters
of the same type occur immediately adjacent to each other, they are
indicated thus:
1 rU-2a 1 aTa-a.
------- and -------
1 tU3a 1 tA2at
The small-letter groups are of vital importance to the classification
system, as they are of relatively infrequent occurrence, constituting
approximately 7 to 10 percent of all patterns. Generally speaking,
since these patterns are of such rare occurrence, their very presence
often enables the classifier to dispense with the usual subsecondary
classification and the major division which in the majority of cases
are used in the larger groups.
THE SUBSECONDARY CLASSIFICATION (GROUPING OF LOOPS AND WHORLS): In
classifying prints it is necessary to subdivide the secondary groups.
This is accomplished by grouping according to the ridge counts of
loops and the ridge tracings of whorls. The first of the groups filed
in order, which it will be necessary to so subdivide, would ordinarily
be the
1 R
---
1 R
group where no small letters appear. The Federal Bureau of
Investigation, however, has found it necessary to extend this division
to many of the small-letter groups which become cumbersome. The
subsecondary is placed on the classification line just to the right of
the secondary. Ridge counts are translated into small and large,
represented by symbols I and O. The whorl tracings are brought up as
I, M, or O denoting inner, meeting or outer ridge tracings of the
whorl types. Only six fingers may be involved in the subsecondary--numbers
2, 3, 4, 7, 8, and 9.
A ridge count of 1 to 9, inclusive, in the index fingers is brought up
into the subsecondary formula as I. A count of 10 or more is brought
up as O. In the middle fingers a count of from 1 to 10, inclusive, is
brought up as I, and 11 or more is O. In the ring fingers a count of
from 1 to 13 is brought up as I, and 14 or more is O. A loop
subsecondary could appear in the classification formula as
OIO.
---
IIO
Analyzing this example of a subsecondary, one will know that in the
index, middle, and ring fingers of the right hand there are counts of
over 9, under 11, and over 13, while in the left hand there are in the
index, middle, and ring fingers, counts of under 10, under 11, over
13, respectively. The subsecondary classification, therefore, relates
to the groupings of the prints, and no difficulty should be
experienced in ascertaining whether the I and O arrangement in the
subsecondary relates to loops or whorls when analyzing a
classification, because this information can be obtained from the
primary classification. Figure 350 is an example illustrating the
subsecondary in addition to other divisions of the classification
formula.
[Illustration: 350]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| |
-----------------------------|-------------|
SCARS AND MARKS |PLACE OF |
|BIRTH | 26 5 R OOO 12
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | 12 W MOI
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT LITTLE
| | MIDDLE | |
26| 12| 0| 17| 12
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
\ | R | W | \ | \
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT |4. LEFT RING |5. LEFT LITTLE
| | MIDDLE | |
I| M | 18| I| 15
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
W | W | / | W | /
---------------------------------------------------------------------------
The chart, figure 351, will illustrate the manner in which the ridge
counts are translated into the symbols I and O so they may be grouped
and sequenced with the whorl tracings I, M and O.
THE MAJOR DIVISION: The major division is placed just to the left of
the primary in the classification formula. Where whorls appear in the
thumbs the major division reflects the whorl tracings just as the
subsecondary does. For example, a major division of I over M in the
primary 5 over 17 would reflect an inner-traced whorl over a
meeting-traced whorl in the thumbs. Where loops appear in the thumbs,
however, a table is used to translate the ridge counts into the small,
medium, or large groups, designated by the letters S, M, L. An
expanding table is used for the right thumb when large-count loops
appear in the left thumb, as shown in the chart (fig. 351). This table
is used because it affords a more equitable distribution of prints as
a whole, for filing purposes within the groups indicated.
[Illustration: 351. Classification Chart]
--RIGHT HAND--
---------------------------------------------------------------------------
R THUMB |R INDEX |R MIDDLE |R RING |R LITTLE
---------------------------------------------------------------------------
WHEN LEFT THUMB| 1-9 = I | 1-10 = I | 1-13 = I |
IS 16 OR LESS |10 AND OVER = O|11 AND OVER = O|14 AND OVER = O|
1-11 = S | | | |
12-16 = M | | | |
17 AND OVER = L| | | |
--------------------RIDGE COUNT OF SECOND SUBSECONDARY---------------------
WHEN LEFT THUMB| 1-5 = S | 1-8 = S | 1-10 = S |
IS 17 OR OVER | 6-12 = M | 9-14 = M |11-18 = M |
1-17 = S |13 AND OVER = L|15 AND OVER = L|19 AND OVER = L|
19-22 = M | | | |
23 AND OVER = L| | | |
---------------------------------------------------------------------------
--LEFT HAND--
---------------------------------------------------------------------------
L THUMB |L INDEX |L MIDDLE |L RING |L LITTLE
---------------------------------------------------------------------------
1-11 = S | | | |
12-16 = M |<------------------VALUES SAME AS ABOVE------------------->
17 AND OVER = L| | | |
---------------------------------------------------------------------------
Table for major divisions of loops:
_Left thumb denominator_ _Right thumb numerator_
{ 1 to 11, inclusive, S (small).
1 to 11, inclusive, S (small) { 12 to 16, inclusive, M (medium).
{ 17 or more ridges, L (large).
{ 1 to 11, inclusive, S (small).
12 to 16, inclusive, M (medium) { 12 to 16, inclusive, M (medium).
{ 17 or more ridges, L (large).
{ 1 to 17, inclusive, S (small).
17 or more ridges, L (large) { 18 to 22, inclusive, M (medium).
{ 23 or more ridges, L (large).
The fingerprint card appearing in figure 352 shows a major division of
L over L, which is obtained by counting the ridges (24 in the right
thumb and 18 in the left thumb) which, according to the table, is
translated into L in both thumbs.
THE FINAL: It is, of course, desirable to have a definite sequence or
order of filing the prints within the subdivided groups. This order is
attained through the use of the final, which is based upon the ridge
count of the loop in the right little finger. It is indicated at the
extreme right of the numerator in the classification. Note figure 352.
If a loop does not appear in the right little finger, a loop in the
left little finger may be used. It is then indicated at the extreme
right of the denominator (fig. 353). If no loops appear in the little
fingers, a whorl may be used to obtain a final, counting from left
delta to core if in the right hand and from right delta to core if in
the left hand. If there are two or more cores (usually applies to
accidental whorls), the ridge count is made from left delta (right
hand) or right delta (left hand) to the core which is the least
number of ridges distant from that delta. An exception is made in the
case of the double loop. The double loop is counted from the delta to
the core of the upright loop. Where loops of a double loop are
horizontal, the nearest core is used. Should both little fingers be a
or t, no final is used. The use of a whorl in a little finger for a
final is required only in connection with a large group or collection
of prints, such as the 32 over 32 primary.
[Illustration: 352]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| | LLL
-----------------------------|-------------| LMM
SCARS AND MARKS |PLACE OF |
|BIRTH | 24 L I R O O O 17
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | L I R O O O
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT 24|2. RIGHT 13|3. RIGHT 31|4. RIGHT 21|5. RIGHT 17
THUMB | INDEX | MIDDLE | RING | LITTLE
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
\ | R | \ | \ | \
---------------------------------------------------------------------------
1. LEFT 18|2. LEFT 16|3. LEFT 13|4. LEFT 18|5. LEFT 20
THUMB | INDEX | MIDDLE | RING | LITTLE
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
/ | R | / | / | /
---------------------------------------------------------------------------
THE KEY: The key is obtained by counting the ridges of the first loop
appearing on the fingerprint card (beginning with the right thumb),
exclusive of the little fingers which are never considered for the key
as they are reserved for the final. The key, no matter where found, is
always placed to the extreme left of the numerator of the
classification formula (fig. 353).
_Extensions_
THE SECOND SUBSECONDARY CLASSIFICATION: When a group of fingerprints
becomes so large that it is cumbersome and unwieldy, even though fully
extended, it can be subdivided further by using a second subsecondary
division, which is brought up into the classification formula
directly above the subsecondary, and for which the symbols S, M and L
are used. The following table is used:
_Index_ _Middle_ _Ring_
1 to 5, inclusive, S. 1 to 8, inclusive, S. 1 to 10, inclusive, S.
6 to 12, inclusive, M. 9 to 14, inclusive, M. 11 to 18, inclusive, M.
13 or more, L. 15 or more, L. 19 or more, L.
If this table is referred to, a study of figure 352 will demonstrate
the use of the second subsecondary.
[Illustration: 353]
LEAVE THIS SPACE BLANK| |SEX
+--------------+ | |__________
|FBI No. | | |RACE
+--------------+ |LAST NAME FIRST NAME MIDDLE NAME|
-----------------------------|----------------------------------+----------
SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.
FINGERPRINTED |AND ADDRESS | |(IN.)|
| | |_____|____
| | |DATE OF
-----------------------------| | |BIRTH
RESIDENCE OF PERSON | | |__________
FINGERPRINTED | | |HAIR |EYES
| | | |
-----------------------------|---------------------------------------------
OCCUPATION |ARREST NUMBER|LEAVE THIS SPACE BLANK
| |
-----------------------------|-------------|
SCARS AND MARKS |PLACE OF |
|BIRTH | 22 M 11 U OOO
|-------------|CLASS__________________________
-----------------------------|CITIZENSHIP | L 6 U OMI 13
SIGNATURE OF OFFICIAL |DATE | _ |
TAKING FINGERPRINTS | ||_|CHECK IF |
| | NO CRIMINAL|REF.___________________________
| | RECORD IS |
| | DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT LITTLE
22| 11| MIDDLE 19| O| O
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
\ | \ | \ | W | W
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT M|4. LEFT RING |5. LEFT LITTLE
18| 10| MIDDLE I| I| 13
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
| | | |
---------------------------------------------------------------------------
/ | / | W | W | /
---------------------------------------------------------------------------
WCDX EXTENSION: In the extension used in the Federal Bureau of
Investigation for the large whorl groups, the type of whorl is
designated by the symbols W, C, D, or X for the index fingers and w,
c, d, or x for all other fingers, according to its classification as
defined in figure 354. These symbols are used for subclassification
purposes only and are brought up into the classification formula
directly above the subsecondary in their respective positions, the
right hand being the numerator, the left hand being the denominator.
SPECIAL LOOP EXTENSION: In the all-loop group
(1R-U)
------
(1R-U),
the following special loop extension may be used, utilizing the ridge
counts in fingers Nos. 2, 3, 4, 7, 8, 9, and, if necessary, No. 10:
_Ridge Counts_ _Value_
1 to 4, inclusive 1
5 to 8, inclusive 2
9 to 12, inclusive 3
13 to 16, inclusive 4
17 to 20, inclusive 5
21 to 24, inclusive 6
25 and over 7
The resulting values in this extension are brought up into the
classification formula directly above the subsecondary in their
respective positions, the right hand being the numerator, the left
hand being the denominator.
In addition to the extensions already mentioned, fingerprint groups
may be divided into male and female, and by age (either by year or by
arbitrarily setting an age limit, beyond which a print bearing such an
age would be filed separately in a "Reference" or a "Presumptive Dead"
file).
In the files of the Federal Bureau of Investigation, all prints
bearing an age of 55 through 74 are filed in the "Reference" group and
all prints bearing an age of 75 years or more are filed in the
"Presumptive Dead" file. Persons 75 years of age or older, in regard
to crime, may be considered as generally inactive and thus are filed
as "Presumptive Dead." Such a group provides for removing from the
other files the cards concerning those of whom no notice is ever
received as to death.
A separate file should be maintained for deceased persons, for
possible future reference.
A separate file should be maintained for all prints bearing
amputations and which have an unequivocal statement or marking from
the contributor to that effect.
Permanent scars also may be utilized for this purpose, giving three
more groupings: those prints having permanent scars in the right hand,
those having a scar in the left, and those in which scars appear in
both hands. A separate file may be maintained for mutilated prints
whether or not the permanent-scar division is used. This is usually
composed of prints so badly mutilated, or so mutilated about the cores
and deltas, that intentional mutilation is suspected.
[Illustration: 354]
+--------------+ +--------------+ +--------------+ +--------------+
| WHORL | |CENTRAL POCKET| | DUAL LOOP | | ACCIDENTAL |
| -W- | | LOOP | | -D- | | -X- |
| | | | | | | |
|[Illustration]| |[Illustration]| |[Illustration]| |[Illustration]|
+--------------+ +--------------+ +--------------+ +--------------+
PATTERN HAVING PATTERN HAVING TWO SEPARATE TWO OR MORE
ONE CORE. LINE ONE CORE. LINE AND DISTINCT DIFFERENT TYPES
DRAWN FROM DRAWN FROM LOOPS IN ONE PATTERN.
DELTA TO DELTA DELTA TO DELTA ANY UNUSUAL
CUTS ONE OR CUTS NO PATTERN NOT
MORE RECURVES RECURVES DEFINED IN
OTHER
CLASSIFICATIONS
CHAPTER V
_Classification of Scarred Patterns--Amputations--Missing at Birth_
_Classification of scarred patterns_
Emphasis should be placed upon the necessity for fully referencing all
scarred patterns. In connection with their proper classification, the
following rules should be observed:
- When an impression is so scarred that neither the general
type of pattern nor the ridge tracing or count can be
determined with reasonable accuracy, the impression should
be given both the general type value and the
subclassification value of the corresponding finger of the
other hand.
- When an impression is partially scarred, i.e., large scars
about the core so that the _general type_ cannot be
determined with _reasonable accuracy_, but the ridges allow
reasonably accurate subclassifications by ridge tracings or
counting, the impression should be given the primary value
of the pattern of the corresponding finger and the
subclassification value as indicated by the ridges of
partially scarred impressions.
- When an impression is partially scarred and the general
type of pattern can be determined with reasonable accuracy,
but the ridges cannot be traced or counted so as to fall
within the proper subsecondary classification, the
impression should be given the ridge count or tracing value
of the corresponding finger of the other hand, if the
corresponding finger is of the same general type. If the
corresponding finger is not of the same general type, the
scarred impression should be given the probable value and
referenced to all other possibilities.
- When an impression is so scarred that neither the general
type of pattern nor the ridge tracing or count can be
determined with reasonable accuracy, and it so happens that
the corresponding finger of the other hand is similarly
scarred, both patterns are given the arbitrary value of
whorls with meeting tracings.
In figure 355, the pattern is entirely obliterated. It could have been
a small whorl, a small ulnar or radial loop, an arch, or a tented
arch. If the opposite finger were an arch or tented arch or whorl,
this impression would be classified as arch, tented arch, or whorl
(with the same tracing). If the opposite finger were a small-count
loop, this would be classified as a loop of the same count. If the
opposite finger were a large-count loop, this impression would be
given the count of the opposite finger even though it could never have
had that count. If the opposite finger were scarred in the same
fashion or were amputated or missing, both impressions would be
classified as whorls with meeting tracings.
In figure 356, the general type of the pattern could have been loop
(ulnar if in the right hand) or whorl. If the opposite finger were a
whorl this would be classified as a whorl, and with the same tracing.
If a radial loop were opposite, this would be classified as an ulnar
loop (if in the right hand). The ridge count can be obtained with a
fair degree of accuracy. If an arch or tented arch were opposite, this
impression would be classified as a loop because it looks as if it had
been a loop.
[Illustration: 355]
[Illustration: 356]
[Illustration: 357]
[Illustration: 358]
In figure 357, the ridge count cannot be determined accurately but it
would be classified as a loop, no matter what the opposite finger
might be. If the opposite finger were a loop with a count of from 6 to
17, this impression would be given that count. If the count of the
opposite loop were less or more than 6 to 17, the count for this
finger would be given I or O in the subsecondary classification
depending upon whether the opposite finger was I or O, but would not
be given less than 6 nor more than 17 counts as its possibility is
limited to those counts.
A pattern with a scar similar to either scar in figures 358 and 359
would always be given a loop as it could be seen readily that there
was no possibility of its having been any other type of pattern.
[Illustration: 359]
_Classification of amputations and fingers missing at birth_
When one or more amputations appear upon a fingerprint card, it may be
filed separately from those having no amputations in order to
facilitate searching. It is to be noted that before it may be filed in
the amputation group, the card must contain a definite and unequivocal
statement or marking by the contributor to the effect that a certain
finger or fingers have been amputated or were missing at birth. This
prevents the appearance on later cards of impressions of fingers
thought to have been amputated but which in reality were merely
injured and bandaged when previous prints were submitted.
If one finger is amputated, it is given a classification identical
with that of the opposite finger, including pattern and ridge count,
or tracing, and referenced to every other possible classification.
If two or more fingers are amputated, they are given classifications
identical with the fingers opposite, with no additional references.
If two amputated fingers are opposite each other, both are given the
classification of whorls with meeting tracings.
When a fingerprint card bearing a notation of fingers missing at birth
is classified, the missing fingers should be treated as amputations in
that they are given the identical classifications of the opposite
fingers and are filed in the amputation group. As these fingers are
missing from a prenatal cause, they would have always received the
identical classification of the opposite finger on any previous
occasion.
If all 10 fingers are amputated or missing at birth, the
classification will be
M 32 W MMM.
-----------
M 32 W MMM
If both hands are amputated or missing at birth, the footprints should
be taken as they, too, bear friction ridges with definite patterns. A
footprint file is maintained by the FBI for identification purposes in
instances where the subject has all fingers amputated or missing at
birth.
Partially amputated fingers often present very complex problems and
careful consideration should be given to them. The question often
arises as to the appropriate groups in which they should be filed,
i.e., amputations or nonamputations. As no definite rule may be
applied, it is a matter of experience and judgment as to their
preferred classification.
In those instances in which a partially amputated finger has half or
more than half of the pattern area missing, it is given the
classification of the opposite finger. It will be filed in the
amputation group under the classification of the opposite finger and
reference searches should be conducted in all possible classifications
in the nonamputation groups. If two or more of the fingers are
amputated in this manner, they are given the classification of the
opposite fingers only and are governed by the rules concerning
amputations.
Generally, a "tip amputation," or one which has less than half of the
first joint amputated, will always be printed in the future.
Therefore, a partially amputated finger with less than half of the
pattern area missing is classified as it appears and is referenced to
the opposite finger. It will be filed in the nonamputation group and
reference searches should be conducted under the classification of the
opposite finger, and in the amputation group. It must be referenced
this way even though it never could have originally had the
classification of the opposite finger.
_Classification of bandaged or imprinted fingers_
As noted in the chapter pertaining to "Problems in the Taking of Inked
Fingerprints," an indication to the effect "recently injured,
bandaged" is not sufficient to file a fingerprint card. It is obvious
that a fingerprint card bearing these notations cannot be properly
classified or filed. If the injury is temporary, and if possible,
these prints should not be taken until after healing.
If fingers are injured to the extent that it is impossible to secure
inked impressions by special inking devices, the unprinted fingers are
given classifications identical with the classifications of the
fingers opposite. If only one finger is lacking, reference searches
should be conducted in every possible classification. If more than one
finger is lacking, they should be given the classifications of the
opposite fingers, but no reference searches should be conducted. If
there are two lacking, opposite each other, they should be classified
as whorls with meeting tracings.
If, however, in the case of an injured finger, observation is made of
the ridges of the finger itself and indicated on the print, this
classification should be, insofar as it is possible, utilized. For
example, a missing impression labeled "ulnar loop of about 8 counts"
by the individual taking the prints, should be searched in the
subsecondary as both I and O but should not be referenced as a pattern
other than a loop. If the finger is used as the final, or key, it
should be searched enough counts on each side of 8 to allow for
possible error in the counting by the contributor using his naked
eye.
CHAPTER VI
_Filing Sequence_
The sequence must be arranged properly at all times to make possible
the most accurate work. Prints are sequenced and filed in this order,
according to:
I. _Primary:_
1 32.
- to --
1 32
In the primary classification the denominator remains constant until
all numerator figures have been exhausted from 1 to 32. All prints
with the primary 1 over 1 are filed together. These are followed by 2
over 1, 3 over 1, 4 over 1, etc., until 32 over 1 is reached. The next
primary is 1 over 2, then 2 over 2, etc., until 32 over 2 is reached.
Eventually, through the use of each denominator figure and the
elimination of each numerator over each denominator, the 32 over 32
primary will be reached.
Even in the smaller collections of fingerprints, it will be found that
the groups which are arranged under the individual primaries filed in
sequence, from 1 over 1 to 32 over 32, will be too voluminous for
expeditious searching.
II. _Secondary:_
A. Secondary small-letter group:
A rW3r.
- to ----
A rW3r
Most intricate of all the individual sequences is the small-letter
sequence. It is less difficult if the following method is used:
1. Sequence according to the patterns in the index fingers, grouped
A W.
- to -
A W
When small letters are present, there are 25 possible combinations
which can appear in the index fingers. They are as follows:
A T R U W
- - - - -
A A A A A
A T R U W
- - - - -
T T T T T
A T R U W
- - - - -
R R R R R
A T U R W
- - - - -
U U U U U
A T U R W
- - - - -
W W W W W
2. Within each group sequence:
a. The denominator, by--
(1) Count of the small letters (lesser preceding the greater).
(2) Position of the small letters (those to the left preceding those
to the right).
(3) Type of small letter (sequence a, t, r).
b. The numerator, by--
(1) Count.
(2) Position.
(3) Type.
Thus
A T
- precedes -
A A
A A
--- precedes ---
rAt A3t
A A
-- precedes --
aA Aa
A A
-- precedes --
At Ar
aA aAa
--- precedes ---
aAr aAr
rA Ar
---- precedes ----
aA2a aA2a
aAtat aAtar
----- precedes -----
tA3r tA3r
The following table represents the full sequence of the denominator of
the group having A over A in the index fingers. The full sequence as
listed may be used as the numerator for each denominator as set out
below. Following the group with A over A in the index fingers is the
group with T over A in the index fingers, the sequence being the same
otherwise. Then R over A, U over A, A over T to rW3r over rW3r.
A tAra aA2at tA2tr
aA tArt aA2ar tAtra
tA tA2r aAata tAtrt
rA rA2a aAa2t tAt2r
Aa rAat aAatr tAr2a
At rAar aAara tArat
Ar rAta aAart tArar
aAa rA2t aAa2r tArta
aAt rAtr aAt2a tAr2t
aAr rAra aAtat tArtr
tAa rArt aAtar tA2ra
tAt rA2r aA2ta tA2rt
tAr A3a aA3t tA3r
rAa A2at aA2tr rA3a
rAt A2ar aAtra rA2at
rAr Aata aAtrt rA2ar
A2a Aa2t aAt2r rAata
Aat Aatr aAr2a rAa2t
Aar Aara aArat rAatr
Ata Aart aArar rAara
A2t Aa2r aArta rAart
Atr At2a aAr2t rAa2r
Ara Atat aArtr rAt2a
Art Atar aA2ra rAtat
A2r A2ta aA2rt rAtar
aA2a A3t aA3r rA2ta
aAat A2tr tA3a rA3t
aAar Atra tA2at rA2tr
aAta Atrt tA2ar rAtra
aA2t At2r tAata rAtrt
aAtr Ar2a tAa2t rAt2r
aAra Arat tAatr rAr2a
aArt Arar tAara rArat
aA2r Arta tAart rArar
tA2a Ar2t tAa2r rArta
tAat Artr tAt2a rAr2t
tAar A2ra tAtat rArtr
tAta A2rt tAtar rA2ra
tA2t A3r tA2ta rA2rt
tAtr aA3a tA3t rA3r
B. Secondary loop and whorl group:
R W.
- to -
R W
When no small letters are present, there are 9 possible combinations
which can appear in the index fingers. They are as follows:
R U W
- - -
R R R
R U W
- - -
U U U
R U W
- - -
W W W
At this point it is well to note that it may be preferable in some
instances where small files are concerned to use only a portion of the
classification formula in the filing sequence. In such cases, only
those parts of the filing sequence which are necessary should be used
along with the final and key.
III. _Subsecondary:_
III OOO.
--- to ---
III OOO
The sequence of the subsecondary is as follows:
III IIM IIO IMI IMM IMO IOI
--- --- --- --- --- --- ---
III III III III III III III
IOM IOO MII MIM MIO MMI MMM
--- --- --- --- --- --- ---
III III III III III III III
MMO MOI MOM MOO OII OIM OIO
--- --- --- --- --- --- ---
III III III III III III III
OMI OMM OMO OOI OOM OOO OOO,
--- --- --- --- --- --- etc., to ---
III III III III III III OOO
each numerator in turn becoming the denominator for the complete
sequence of numerators as listed above.
IV. _Major:_
The following sequence is used when loops appear in both thumbs:
S M L S M L S M L
- - - - - - - - -
S S S M M M L L L
When whorls appear in both thumbs the sequence is:
I M O I M O I M O
- - - - - - - - -
I I I M M M O O O
When a whorl appears in the right thumb and a loop in the left, the
sequence is:
I M O I M O I M O
- - - - - - - - -
S S S M M M L L L
When a loop appears in the right thumb and a whorl in the left, the
sequence is:
S M L S M L S M L
- - - - - - - - -
I I I M M M O O O
V. _Second Subsecondary:_
SSS LLL.
--- to ---
SSS LLL
The sequence for filing the second subsecondary is as follows:
SSS SSM SSL SMS SMM SML
--- --- --- --- --- ---
SSS SSS SSS SSS SSS SSS
SLS SLM SLL MSS MSM MSL
--- --- --- --- --- ---
SSS SSS SSS SSS SSS SSS
MMS MMM MML MLS MLM MLL
--- --- --- --- --- ---
SSS SSS SSS SSS SSS SSS
LSS LSM LSL LMS LMM LML
--- --- --- --- --- ---
SSS SSS SSS SSS SSS SSS
LLS LLM LLL, LLL,
--- --- --- etc., to ---
SSS SSS SSS LLL
each group of the numerator becoming in turn the denominator for the
complete sequence of numerators as listed above.
VI. _W C D X Extensions:_
W xX3x.
- to ----
W xX3x
The sequence is as follows: Prints with _c_, _d_, or _x_ in any finger
other than the index fingers constitute the small-letter group. A
sample of the sequence follows:
W cWc xWd Wdx
cW cWd xWx Wxc
dW cWx W2c Wxd
xW dWc Wcd W2x
Wc dWd Wcx cW2c
Wd dWx Wdc cWcd
Wx xWc W2d cWcx
As may be readily seen, the sequence proceeds in the same fashion as
the a, t, r, small-letter sequence.
VII. Special Loop Extension used by the _Federal Bureau of
Investigation:_
111 777.
--- to ---
111 777
The following is a partial sequence for filing this extension:
111 112 113 114 115 116 117
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
121 122 123 124 125 126 127
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
131 132 133 134 135 136 137
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
141 142 143 144 145 146 147
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
151 152 153 154 155 156 157
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
161 162 163 164 165 166 167
--- --- --- --- --- --- ---
111 111 111 111 111 111 111
171 172 173 174 175 176 177 777.
--- --- --- --- --- --- --- etc., to ---
111 111 111 111 111 111 111 777
No matter how many of these divisions may be used, the order should
remain the same; and no matter how many of these divisions are used,
each individual group should be sequenced by:
VIII. _Final:_
Filed in numerical sequence from 1 out. For example, assume that there
are 15 prints in a group having a final of 14. All of these should be
filed together and followed by those prints in the same group having a
final of 15, etc.
IX. _Key:_
All prints appearing in a designated final group are arranged by key
in numerical sequence from 1 out. For example, assume that there are 5
prints in a group having a key of 14. All of these should be filed
together and followed by those prints in the same group having a key
of 15, etc.
CHAPTER VII
_Searching and Referencing_
_Searching_
When searching a print through the fingerprint files in order to
establish an identification, it should be remembered that the
fingerprint cards are filed in such a way that all those prints having
the same classification are together. Thus, the print being searched
is compared only with the groups having a comparable classification,
rather than with the whole file.
After locating the proper group classification, the searcher should
fix in his mind the one or two most outstanding characteristics of the
patterns of the current print and look for them among the prints in
file. If a print is found which has a characteristic resembling one
upon the current print, the two prints should be examined closely to
determine if identical. To avoid making an erroneous identification,
the searcher should be exceedingly careful to ascertain that the
prints being compared are identical in all respects before identifying
one against the other.
To establish identity, it is necessary to locate several points of
identity among the characteristics of the prints. The number of
identical characteristics is left to the discretion of the individual
but he should be absolutely certain that the prints are identical
before treating them as such. Characteristics need not appear within
the pattern area, since any ridge formation is acceptable. Quite often
excellent ridge detail appears in the second joint of the finger. The
characteristics used to establish an identification are shown in
figure 102.
The final and the key may be considered control figures for searching
prints. They limit the number of prints it is necessary to search in a
group to those prints having finals and keys closely related to the
final and key of the print being searched.
Due to the possibility of visual misinterpretation, distortion by
pressure, or poor condition of the ridge detail of the prints in file,
it is advisable to allow a margin for such discrepancies. Except in
cases where the ridge count of the final and/or key is questionable on
the print being searched, the following procedure is used:
Of the prints within any group classification, only those prints are
examined which have a final within 2 ridge counts on each side of the
final of the print being searched. For example, if the print to be
searched has a final of 17, all prints bearing a final 15 through 19
will be compared with it.
Within the final of any group classification, only those prints are
examined which have a key within 2 ridge counts on each side of the
key of the print being searched. For example, if the print to be
searched has a key of 20, all prints bearing a key of 18 through 22
will be compared with it.
In figure 352, it will be noted that there are 17 ridge counts
appearing in the right little finger and this number is used as the
final. It will also be noted that there is a loop of 24 ridge counts
in the right thumb and this number is used as the key inasmuch as it
is the first loop. In this example, the print is searched in the group
classification which has finals ranging from 15 through 19. Within
this group of finals the prints which have keys ranging from 22
through 26 are examined.
_Referencing_
Too much stress cannot be placed upon the necessity of referencing
questionable patterns, whether it be in the interpretation of the type
of pattern, the ridge count, or the tracing.
The factors which make it necessary are: variation in individual
judgment and eyesight, the amount of ink used, the amount of pressure
used in taking the prints, the difference in width of the rolled
impressions, skin diseases, worn ridges due to age or occupations,
temporary and permanent scars, bandaged fingers, crippled hands, and
amputation.
_For the highest degree of accuracy, all rolled impressions should be
checked by the plain impressions_, which generally are not distorted
by pressure. This also helps prevent error caused by the reversal or
mixing of the rolled impressions out of their proper order. For the
same reason, as much of the counting and tracing should be done in the
plain impressions as it is possible to do.
If there is any doubt as to which of two or more classifications
should be assigned to a given pattern, it is given the preferred
classification and reference searches are conducted in all other
possible classifications. For example, if on a print with the
preferred classification
1 A
----
1 Aa
it is questionable whether the left middle finger should be a plain
arch, a tented arch, or a radial loop, the print is searched in the
1 A
----
1 Aa
group, and reference searches are conducted in the
1 A
----
1 At
and
1 A
----
1 Ar
groups. For further illustration, a print is given a preferred primary
classification of
1,
-
1
although the ridge detail on the right thumb is so formed as to
resemble a whorl. The search is completed first in the preferred
1
-
1
primary classification and a reference search is then conducted in the
1
--
17
primary.
All ridge counts that are "line counts," i.e., when one more or one
less count would change the designation of the loop from I to O or
from S to M, etc., must be searched in both groups. For example, in a
print classified
16 M 1 U III 10,
---------------
M 1 U III
if the ridge count of the right middle finger is 10 and the count in
the right thumb is 16 (as indicated by the key), the print would be
searched first as classified, then reference searches would be
conducted in the following groups:
M 1 U IOI, L 1 U III, L 1 U IOI
--------- --------- and ---------
M 1 U III M 1 U III M 1 U III
When there is doubt concerning the tracing of a whorl, it should be
treated in the same fashion. For example, if in the classification
O 5 U
------
I 17 U
doubt existed as to whether the tracing of the right thumb might not
be a meeting tracing, the print would be searched as classified, and a
reference search would be conducted in
M 5 U.
------
I 17 U
If there is no doubt concerning the ridge count used for the final, it
is enough to search out of the group only those prints containing a
final within 2 ridge counts on each side of the final on the print
being searched. When, however, there is doubt concerning the ridge
count of the final, the print should be searched 2 ridge counts on
each side of the two extremes of possibility. For example, if it were
possible for a final to be 6, 7, 8, or 9 ridge counts, the print
should be searched through that part of the group bearing finals of
from 4 through 11.
The above explanation pertaining to the final also applies to the key.
All prints bearing amputations should be referenced to the necessary
files containing prints other than amputations for reference searches.
In instances where only one finger is amputated, reference searches
are conducted in all possible classifications, including all possible
ridge counts or tracings. For example, a print containing the
classification:
AMP
4 S 1 U III 6
-------------
S 1 U III
with the right index finger amputated, the left index finger being an
ulnar loop, would be searched first in the amputation group for the
classification, then reference searches would be conducted in the
following groups in the nonamputation files:
S 1 U III S 1 T II S 17 W III
--------- --------- ----------
S 1 U III S 1 U III S 1 U III
S 1 U OII S 1 R III S 17 W MII
--------- --------- ----------
S 1 U III S 1 U III S 1 U III
S 1 A II S 1 R OII S 17 W OII
--------- --------- ----------
S 1 U III S 1 U III S 1 U III
All prints bearing unprinted or badly crippled fingers are filed in
the nonamputation files, and reference searches are conducted in the
amputation group.
For the purpose of determining if it is feasible to conduct reference
searches in all possible classifications, the method of referencing
amputations is applied to completely scarred patterns (Chapter titled
"Scarred Patterns--Amputations--Missing at Birth"). For example, a
print bearing the preferred classification:
13 O 17 W OOO 14
----------------
L 17 U OOI
with the left middle finger completely scarred, the right middle
finger being an ulnar loop with a ridge count of 13, would be searched
first in the group for that classification, then reference searches
would be conducted in the following groups:
O 17 W OOO O 17 W O 19 W OOO
---------- ------- ----------
L 17 U OII L 17 Ur L 17 U OOI
O 17 W O 19 W OOO
------- ----------
L 17 Ua L 17 U OII
O 17 W O 19 W OOO
------- ----------
L 17 Ut L 17 U OMI
The referencing of partial scars is a problem in which many factors
are present. A full explanation of the scars, their preferred
classifications and their references is made in the chapter,
"Classification of Scarred Patterns--Amputations--Missing at Birth."
When the age extension is utilized and a "Reference" group and a
"Presumptive Dead" file are maintained, it is suggested that a general
allowance of 5 years be considered to allow for a discrepancy in
prints bearing the ages of 50 years or older.
In the files of the Federal Bureau of Investigation the various age
groups are as follows:
1-54 "Regular" file.
55-74 "Reference" file.
75 and over "Presumptive Dead" file.
Reference searches for the preceding groups are conducted in the
following manner:
50-54 Referenced to "Reference" file.
70-74 Referenced to "Presumptive Dead" file and "Regular" file.
75-79 Referenced to "Reference" file and "Regular" file.
80 and older Referenced to "Regular" file only.
If no age is given, it should be searched first in the regular file
and reference searches should be conducted in the "Reference" group
and the "Presumptive Dead" file.
When separate male and female files are maintained, there may be doubt
as to the sex of a subject due to a discrepancy between the sex
indicated and the name and the description and picture. In such case
try to determine the sex from the description and the size of the
prints, then reference the print to the other file. A Photostat copy
can be made and placed in the other file until the true sex can be
determined.
CHAPTER VIII
_How To Take Inked Fingerprints_
The equipment required for taking fingerprints consists of an inking
plate, a cardholder, printer's ink (heavy black paste), and a roller.
This equipment is simple and inexpensive.
In order to obtain clear, distinct fingerprints, it is necessary to
spread the printer's ink in a thin even coating on a small inking
plate. A roller similar to that used by printers in making galley
proofs is best adapted for use as a spreader. Its size is a matter
determined by individual needs and preferences; however, a roller
approximately 6 inches long and 2 inches in diameter has been found to
be very satisfactory. These rollers may be obtained from a fingerprint
supply company or a printing supply house.
[Illustration: 360. Fingerprint stand.]
An inking plate may be made from a hard, rigid, scratch-resistant
metal plate 6 inches wide by 14 inches long or by inlaying a block of
wood with a piece of glass one-fourth of an inch thick, 6 inches wide,
and 14 inches long. The glass plate by itself would be suitable, but
it should be fixed to a base in order to prevent breakage. The inking
surface should be elevated to a sufficient height to allow the
subject's forearm to assume a horizontal position when the fingers are
being inked. For example, the inking plate may be placed on the edge
of a counter or a table of counter height. In such a position, the
operator has greater assurance of avoiding accidental strain or
pressure on the fingers and should be able to procure more uniform
impressions. The inking plate should also be placed so that the
subject's fingers which are not being printed can be made to "swing"
off the table to prevent their interfering with the inking process. A
fingerprint stand such as that shown in figure 360 may be purchased
from fingerprint supply companies. The stand is made of hardwood and
measures approximately 2 feet in length, 1 foot in height and width.
This stand contains a cardholder and a chrome strip which is used as
the inking plate. Two compartments used to store blank fingerprint
cards and supplies complete the stand. This equipment should be
supplemented by a cleansing fluid and necessary cloths so that the
subject's fingers may be cleaned before rolling and the inking plate
cleaned after using. Denatured alcohol and commercially available
cleaning fluids are suitable for this purpose.
[Illustration: 361. Fingerprints properly taken.]
PERSONAL |ROE RICHARD RANDOLPH |SEX
IDENTIFICATION | | MALE
|LAST NAME FIRST NAME MIDDLE NAME|--------------
|----------------------------------|RACE
-------------------------| | W
FINGERPRINTS SUBMITTED BY| |--------------
| |HT. |WT.
|----------------------------------|(Inches)|
|SIGNATURE OF PERSON FINGERPRINTED | 71 | 170
| |--------------
| 1655 Grant Avenue |DATE OF BIRTH
|----------------------------------|6/6/42
-------------------------| Chicago, Illinois |--------------
FINGERPRINTED BY |--------------------------------- |HAIR |EYES
|RESIDENCE OF PERSON FINGERPRINTED |BR |BR
|-------------------------------------------------
-------------------------|DATE FINGERPRINTED|LEAVE THIS SPACE BLANK
PERSON TO BE NOTIFIED IN |8/12/62 |
CASE OF EMERGENCY |------------------|CLASS
NAME Thomas L. Roe |PLACE OF BIRTH | -------------------------
-------------------- |Omaha, Neb. |
ADDRESS 1655 Grant Avenue|------------------|
----------------- |CITIZENSHIP |
Chicago, Illinois|American |REF.
-------------------------|------------------| --------------------------
See Reverse Side for |SCARS AND MARKS |
Further Instructions |Appendectomy |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT
| | MIDDLE | | LITTLE
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
| | | |
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT MIDDLE|4. LEFT RING |5. LEFT LITTLE
| | | |
[Illustration]|[Illustration]|[Illustration]|[Illustration]|[Illustration]
---------------------------------------------------------------------------
| | | |
---------------------------------------------------------------------------
LEFT FOUR FINGERS |LEFT |RIGHT |RIGHT FOUR FINGERS
TAKEN SIMULTANEOUSLY |THUMB |THUMB |TAKEN SIMULTANEOUSLY
| | |
[Illustration] |[Illustration]|[Illustration]|[Illustration]
The fingerprints should be taken on 8- by 8-inch cardstock, as this
size has generally been adopted by law enforcement because of facility
in filing and desirability of uniformity. Figure 361 shows
fingerprints properly taken on one of the standard personnel
identification cards from the Federal Bureau of Investigation. From
this illustration, it is evident there are two types of impressions
involved in the process of taking fingerprints. The upper 10 prints
are taken individually--thumb, index, middle, ring, and little fingers
of each hand in the order named. These are called "rolled"
impressions, the fingers being rolled from side to side in order to
obtain all available ridge detail. The smaller impressions at the
bottom of the card are taken by simultaneously printing all of the
fingers of each hand and then the thumb without rolling. These are
called "plain" or "fixed" impressions and are used as a check upon the
sequence and accuracy of the rolled impressions. Rolled impressions
must be taken carefully in order to insure that an accurate
fingerprint classification can be obtained by examination of the
various patterns. It is also necessary that each focal point (cores
and all deltas) be clearly printed in order that accurate ridge counts
and tracings may be obtained.
In preparing to take a set of fingerprints, a small daub of ink should
be placed on the inking glass or slab and thoroughly rolled until a
very thin, even film covers the entire surface. The subject should
stand in front of and at forearm's length from the inking plate. In
taking the rolled impressions, the side of the bulb of the finger is
placed upon the inking plate and the finger is rolled to the other
side until it faces the opposite direction. Care should be exercised
so the bulb of each finger is inked evenly from the tip to below the
first joint. By pressing the finger lightly on the card and rolling in
exactly the same manner, a clear rolled impression of the finger
surface may be obtained. It is better to ink and print each finger
separately beginning with the right thumb and then, in order, the
index, middle, ring, and little fingers. (Stamp pad ink, printing ink,
ordinary writing ink, or other colored inks are not suitable for use
in fingerprint work as they are too light or thin and do not dry
quickly.)
If consideration is given the anatomical or bony structure of the
forearm when taking rolled impressions, more uniform impressions will
be obtained. The two principal bones of the forearm are known as the
radius and the ulna, the former being on the thumb side and the latter
on the little finger side of the arm. As suggested by its name, the
radius bone revolves freely about the ulna as a spoke of a wheel about
the hub. In order to take advantage of the natural movement in making
finger impressions, the hand should be rotated from the awkward to the
easy position. This requires that the thumbs be rolled toward and the
fingers away from the center of the subject's body. This process
relieves strain and leaves the fingers relaxed upon the completion of
rolling so that they may be lifted easily from the card without danger
of slipping which smudges and blurs the prints. Figures 362 and 363
show the proper method of holding a finger for inking and printing a
rolled impression.
The degree of pressure to be exerted in inking and taking rolled
impressions is important, and this may best be determined through
experience and observation. It is quite important, however, that the
subject be cautioned to relax and refrain from trying to help the
operator by exerting pressure as this prevents the operator from
gaging the amount needed. A method which is helpful in effecting the
relaxation of a subject's hand is that of instructing him to look at
some distant object and not to look at his hands. The person taking
the fingerprints should stand to the left of the subject when printing
the right hand, and to the right of the subject when printing the left
hand. In any case, the positions of both subject and operator should
be natural and relaxed if the best fingerprints are to be obtained.
To obtain "plain" impressions, all the fingers of the right hand
should be pressed lightly upon the inking plate, then pressed
simultaneously upon the lower right hand corner of the card in the
space provided. The left hand should be similarly printed, and the
thumbs of both hands should be inked and printed, without rolling, in
the space provided. Figures 364 and 365 show the correct method of
taking plain impressions of the fingers and thumbs.
[Illustration: 362. Proper method of holding finger.]
[Illustration: 363. Proper method of printing rolled impressions.]
[Illustration: 364. Proper method of taking plain impressions of
fingers.]
[Illustration: 365. Proper method of taking plain impressions of
thumbs.]
CHAPTER IX
_Problems in the Taking of Inked Fingerprints_
From time to time various problems arise concerning the taking of
inked impressions. It is believed that these problems can be divided
into four phases:
- Mechanical operation
- Temporary disabilities
- Permanent disabilities
- General
_Mechanical operation_
In order to take good fingerprints, the necessary equipment should be
maintained in a neat and orderly manner at all times.
Poor impressions are usually caused by one of the following faults:
1. The use of poor, thin, or colored ink, resulting in impressions
which are too light and faint, or in which the ink has run,
obliterating the ridges. The best results will be obtained by using
heavy black printer's ink, a paste which should not be thinned before
using. This ink will dry quickly and will not blur or smear with
handling.
2. Failure to clean thoroughly the inking apparatus and the fingers of
foreign substances and perspiration, causing the appearance of false
markings and the disappearance of characteristics. Windshield cleaner,
gasoline, benzine, and alcohol are good cleansing agents, but any
fluid may be used. In warm weather each finger should be wiped dry of
perspiration before printing.
3. Failure to roll the fingers fully from one side to the other and to
ink the whole area from tip to below the first fissure. The result of
this is that the focal points of the impressions (the deltas or cores)
do not appear. The whole finger surface from joint to tip and from
side to side should appear.
4. The use of too much ink, obliterating or obscuring the ridges. If
printer's ink is used, just a touch of the tube end to the inking
plate will suffice for several sets of prints. It should be spread to
a thin, even film by rolling.
5. Insufficient ink, resulting in ridges too light and faint to be
counted or traced.
6. Allowing the fingers to slip or twist, resulting in smears, blurs,
and false-appearing patterns. The fingers should be held lightly
without too much pressure. The subject should be warned not to try to
help but to remain passive.
The illustrations numbered 366 through 377 show the results of these
faults and show also the same fingers taken in the proper manner.
_Illegible inked prints_
A brief review of the problems of classifying and filing a fingerprint
card in the FBI will help to clarify the FBI's policy concerning the
processing of "bad" inked fingerprints.
The criminal fingerprint file contains the fingerprints of millions of
individuals. The complete classification formula is used. To obtain
it, each inked finger must show all the essential characteristics.
Because of the immense volume of prints it has become necessary to
extend the normal classification formula.
To illustrate this point:
dWdwc
xCdwc
O 32 W OOO 18
I 32 W III
In order to subdivide the 32 over 32 primary still further, the ridge
count of the whorl of the right little finger is used to obtain a
final classification. The extension above the normal classification
formula indicates that each whorl is classified as to the type;
namely, plain whorl (W), double loop (D), central pocket loop (C), and
accidental (X). Accordingly, it is not enough for the FBI
Identification Division to ascertain the general whorl pattern type,
but the deltas and core must show in order to obtain the ridge
tracing, the type of whorl, and also, in some instances, the ridge
count. The complete WCDX extension is outlined in Chapter VI.
Figures 366 to 377 are some examples of improperly and properly taken
inked fingerprints.
An examination of figure 372 shows that it is a whorl. In order to
classify the ridge tracing accurately, however, so that the
fingerprint card can be placed in the correct classification, the left
delta must show. The approximate ridge tracing for the whorl in figure
372 would be MEETING. An examination of the properly taken fingerprint
in figure 373 indicates that the correct ridge tracing is INNER. It
follows that the pattern in figure 372 would not have been placed in
the proper place in file.
[Illustration: 366. Improper.]
[Illustration: 367. Proper.]
[Illustration: 368. Improper.]
[Illustration: 369. Proper.]
[Illustration: 370. Improper.]
[Illustration: 371. Proper.]
[Illustration: 372. Improper.]
[Illustration: 373. Proper.]
The correct whorl tracing is needed to obtain the complete
subsecondary and the major classifications.
It may be noted that both deltas are present in figure 374. This would
enable the technical expert to ascertain the correct ridge tracing,
OUTER. In the core of the whorl, however, there is a heavy amount of
ink which makes it impossible to determine the type of whorl with any
degree of accuracy. If one were to hazard a guess, it would appear to
be a plain whorl. Actually, the correct type of whorl, a double loop,
is clearly visible in figure 375.
It can be ascertained that the pattern in figure 376 is a loop, but an
accurate ridge count cannot be obtained because the left delta does
not appear. The approximate ridge count of this loop is 14 to 16.
This approximation is sufficient for a fingerprint expert to place
this loop in the "O" group of any finger of the subsecondary. The
correct ridge count of this loop is 19, and it appears in illustration
377. The approximate ridge count is not sufficient to place this print
properly in the large files of the FBI because in certain general
complete classification formulas the accurate ridge count is needed to
obtain an extension. These extensions use a smaller grouping of ridge
counts to form a valuation table, and in this way, differ from the
larger grouping of ridge counts which form the basis of the
subsecondary classification. These extensions are called the second
subsecondary and the special loop extension and are outlined in
chapter VI.
[Illustration: 374. Improper.]
[Illustration: 375. Proper.]
[Illustration: 376. Improper.]
[Illustration: 377. Proper.]
There are two additional points which illustrate the FBI's need for
the delta, ridges, and core to show clearly in loops. The first point
is set forth: the ridge count of the loop may be needed to obtain the
key classification. The key classification is an actual ridge count,
and no valuation table is used to obtain a subdivision. The key
classification is used as an integral part of the fingerprint filing
system. The second point is as follows: the ridge count may be needed
to obtain the final classification. The final classification is an
actual ridge count, and no valuation table is used to obtain a
subdivision. The final classification is used as an integral part of
the fingerprint filing system.
The following are just a few examples to illustrate the completeness
of the classification formula used in the FBI fingerprint file:
12 M 9 R OIO 11
S 1 R IOI
Key Major Primary Secondary Subsecondary Final
6 17 aW IIO 9
1 U OII
Key Primary Small letter Subsecondary Final
Secondary
8 S 1 Ua II 6
S 1 U III
Key Major Primary Small letter (Subsecondary Final
Secondary Extension)
SML (Second
SML Subsecondary)
5 0 5 U IOO 14
I 17 U IOO
Key Major Primary Secondary Subsecondary Final
245 (Special Loop
332 Extension)
14 M 1 U IOO 16
S 1 U OII
Key Major Primary Secondary Subsecondary Final
15 I 29 W IOO 19
I 28 W OOI
Key Major Primary Secondary Subsecondary Final
These several examples should help to illustrate the FBI's extended
classification formulas for classifying and filing fingerprints. The
larger collection of fingerprints must of necessity call for a more
detailed analysis of all fingerprint characteristic details. The
closer examination to obtain further fingerprint subdivisions is
dependent on ten legible inked impressions.
The identification officer will understand the problems of accurately
classifying and filing fingerprint cards. He knows there is little
value in placing a fingerprint card in the FBI's files with only an
approximate or an inaccurate classification.
Every fingerprint card filed in the FBI's file is of value to the
particular law enforcement agency which forwarded it, as well as to
all other law enforcement agencies which rely on its being correctly
classified and filed.
_Temporary disabilities_
There are temporary disabilities affecting an individual's hand which
are sometimes beyond the control of the identification officer. These
can be fresh cuts, or wounds, bandaged fingers or finger, occupational
(carpenters, bricklayers, etc.) blisters, and excessive perspiration.
Children, whose ridges are small and fine, would also come under this
heading. Extreme care should be exercised in fingerprinting the
aforementioned.
An indication on the fingerprint card to the effect "fresh cut,
bandaged" is not sufficient to file the fingerprint card. It is
obvious that a fingerprint card bearing these notations cannot be
properly classified and filed. The same situation would occur if there
were a blister on an individual's finger. The blister temporarily
disfigures the ridge detail. When an injury is temporary, the prints,
if at all possible, should not be taken until after the injury has
healed.
Occupational problems (bricklayers, carpenters, etc.) are definitely a
challenge to the identification officer. In some instances, by means
of softening agents (oils and creams), it is possible to obtain
legible inked impressions. It is further suggested that in these cases
a very small amount of ink should be used on the inking plate.
Excessive perspiration can be controlled to some extent by the
identification officer. Excessive perspiration causes the inked
impressions to be indistinct. It is suggested in these cases to wipe
the finger with a cloth and then immediately ink the finger and roll
it on the fingerprint card. This process should be followed with each
finger. It is also suggested that possibly the fingers could be wiped
with alcohol, benzine, or similar fluid which would act as a drying
agent.
In all the above situations, if it is not possible to accurately
classify and file the fingerprint card, the name appearing on the card
will be searched in the alphabetical files and then returned to the
law-enforcement agency.
_Permanent disabilities_
Another phase involves permanent disabilities which can in most cases
be controlled by the identification officer. These can be lack of
fingers (born without), amputations, crippled fingers (bent, broken),
deformities (webbed, extra fingers), and old age.
With respect to lack of fingers, it should be noted that some
individuals are born without certain fingers. The notation "missing"
is not satisfactory because it does not sufficiently explain the
correct situation. It is suggested that "missing at birth" or some
similar notation be made in the individual fingerprint block on the
card. A proper notation concerning this situation will prevent the
fingerprint card from being returned. Figures 378 and 379 illustrate
temporary and permanent disabilities.
[Illustration: 378. Temporary disability.]
[Illustration: 379. Permanent disability.]
Concerning amputations, it is suggested that a proper notation to this
effect appear in the individual fingerprint block or blocks. It is
suggested that if a portion of the first joint of a finger is
amputated, the finger should be inked and printed. A notation
concerning this fact should be made on the fingerprint card in the
individual fingerprint block.
In those cases where all of the fingers are amputated, the inked
footprints should be obtained.
The handling of crippled fingers and certain deformities can be
discussed in a group because they generally present the same problems.
It is not sufficient in all cases to indicate "broken," "bent,"
"crippled." If the fingers are bent or crippled so that they are
touching the palm and cannot be moved, a notation to this effect
should be on the fingerprint card in the proper individual fingerprint
block. However, it is believed that these extreme cases are rare. It
is suggested that the special inking devices used for taking the
prints of deceased individuals be used in taking inked impressions of
bent or crippled fingers.
[Illustration: 380. The spatula, roller, and curved holder used for
taking the inked prints of bent or crippled fingers.]
This equipment, which will be discussed more fully in the section on
printing deceased persons, consists of spatula, small roller, and a
curved holder for the individual finger block. Figure 380 shows the
spatula, roller, and curved holder. It should be further noted in
figure 380 that there are a strip of the entire hand of the
fingerprint card and also individual finger blocks cut from the
fingerprint card. Each of these types can be used in connection with
the curved holder.
Each crippled finger is taken as a separate unit and then the finger
block pasted on a fingerprint card. In figure 381, note the use of the
spatula for applying the ink to a bent or crippled finger; and in
figure 382, observe the use of the curved holder for taking the
"rolled" impression of a bent or crippled finger.
Old age has been placed under permanent disability only for discussion
purposes. The problem is not encountered frequently in taking the
fingerprints of individuals who are arrested. The situation of
crippled fingers due to old age may be met, and it can be handled as
previously suggested. In most cases the problems arise because of the
very faint ridges of the individual. It is believed that in the
majority of cases, legibly inked prints can be taken by using a very
small amount of ink on the inking plate and by using little pressure
in the rolling of the fingers.
[Illustration: 381. The use of the spatula in the application of ink
to the finger.]
[Illustration: 382. The use of the curved holder for taking the
"rolled" impression.]
_Deformities_
If a subject has more than 10 fingers, as occasionally happens, the
thumbs and the next 4 fingers to them should be printed, and any
fingers left over should be printed on the other side of the card with
a notation made to the effect that they are extra fingers. When a
person with more than 10 fingers has an intentional amputation
performed, it is invariably the extra finger on the little finger side
which is amputated.
[Illustration: 383]
It also happens, not infrequently, that a subject will have two or
more fingers webbed or grown together, as in figures 383 and 384,
making it impossible to roll such fingers on the inside. Such fingers
should be rolled, however, as completely as possible, and a notation
made to the effect that they are joined.
Split thumbs, i.e., thumbs having two nail joints, as in figure 385,
are classified as if the joint toward the outside of the hand were not
present. In other words the inner joint is used, and no consideration
whatever is given to the outer joint.
[Illustration: 384]
[Illustration: 385]
_General_
These problems have dealt with the mechanical or operational
processes. However, there are other problems dealing with the
completing of the descriptive information. The fingerprint card may be
returned because of the lack of information in the spaces provided,
such as name, sex, race, height, weight, etc. Any discrepancies in
this information may necessitate the return of the fingerprint card.
The success and value of the FBI's fingerprint files to all law
enforcement agencies are dependent, in a large measure, on the legibly
inked fingerprints taken by law enforcement agencies.
Figure 386 shows an enlarged portion of the bulb of a finger revealing
the microscopic structure of the friction skin. The epidermis consists
of two main layers, namely, the stratum corneum, which covers the
surface, and the stratum mucosum, which is just beneath the covering
surface. The stratum mucosum is folded under the surface so as to form
ridges which will run lengthwise and correspond to the surface
ridges. However, these are twice as numerous since the deeper ridges
which correspond to the middle of the surface ridges alternate with
smaller ones which correspond to the furrows. The sweat pores run in
single rows along the ridges and communicate through the sweat ducts
with the coil sweat glands which are below the entire epidermis. The
friction ridges result from the fusion in rows of separate epidermic
elements, such as the dot shown on the left. Generally speaking, when
an individual bruises or slightly cuts the outer layer or stratum
corneum of the bulb of the finger, the ridges will not be permanently
defaced. However, if a more serious injury is inflicted on the bulb of
the finger, thereby damaging the stratum mucosum, the friction skin
will heal, but not in its original formation. The serious injury will
result in a permanent scar appearing on the bulb of the finger.
[Illustration: 386]
CHAPTER X
_Problems and Practices in Fingerprinting the Dead_
Each year new graves are opened in potter's fields all over the United
States. Into many of them are placed the unknown dead--those who have
lived anonymously or who, through accident or otherwise, lose their
lives under such circumstances that identification seems impossible.
In a majority of such cases, after the burial of the body, no single
item or clue remains to effect subsequent identification. As a result,
active investigation usually ceases and the cases are forgotten,
unless, of course, it is definitely established that a murder has been
committed.
Reliance is too often placed on visual inspection in establishing the
identity of the deceased. This includes having the remains viewed by
individuals seeking to locate a lost friend or relative. The body is
often decomposed. If death was caused by burning, the victim may be
unrecognizable. As a result of many fatal accidents the deceased is
often mutilated, particularly about the face, so that visual
identification is impossible. Yet, in many cases, the only attempt at
identification is by having persons view the remains and the personal
effects.
The recorded instances of erroneous visual identifications are
numerous. In one case a body, burned beyond recognition, was
identified by relatives as that of a 21-year-old man; yet fingerprints
later proved that the corpse was that of a 55-year-old man.
Fingerprints have frequently been instrumental in establishing the
correct identity of persons killed in airplane crashes and incorrectly
"identified" by close relatives.
In one instance a woman found dead in a hotel room was "positively"
identified by several close friends. The body was shipped to the
father of the alleged deceased in another state where again it was
"identified" by close friends. Burial followed. Approximately one
month later the persons who had first identified the body as that of
their friend were sitting in a tavern when the "dead" woman walked
into the room. Authorities were immediately advised of the error; they
in turn advised the authorities in the neighboring state of the
erroneous identification and steps were taken immediately to rectify
the mistake. After permission had been granted by the State Health
Board to exhume the body of the dead woman, fingerprints were taken
and copies were forwarded to the FBI Identification Division. The
finger impressions were searched through the fingerprint files and the
true identity of the deceased was established.
During a 12-month period, the FBI Identification Division received
the fingerprints of 1,708 unknown dead. Of these, 1,298, or almost 76
percent, were identified. The remaining 410 were not identified simply
because fingerprints of these individuals were not in the FBI files.
It should be noted that in these 1,708 cases, it was possible to
secure legible fingerprints of the deceased in the usual manner by
inking the fingers in those instances in which decomposition had not
injured the ridge detail.
[Illustration: 387. Field equipment for disaster identification.]
In addition to the fingerprints of 1,708 unknown dead, the
Identification Division received the fingers and/or the hands of 85
unknown dead individuals. In these cases, decomposition was so far
advanced that it was not possible to secure inked fingerprints in the
regular manner. Of these, 68 bodies, or 80 percent of the group, were
identified. Of the 17 unidentified, the fingerprints of 14 were not in
the FBI files. In three cases decomposition was so far advanced that
all ridge detail had been destroyed.
In order to emphasize what can be accomplished, it is pointed out that
in those cases in which hands and fingers were submitted, the time
which elapsed from death until the specimens were received ranged from
a week to 3 years. Incredible as it may seem, it has been possible to
secure identifiable impressions 3 years after death.
These statistics of achievement in the field of identifying unknown
dead re-emphasize the fact that in all cases involving the
identification of a deceased person, fingerprints should be used as
the medium for establishing a conclusive and positive identification.
Generally speaking, in the course of their work fingerprint operators
find it necessary to take the impressions of three classes of deceased
persons.
They are:
- Those who have died recently, in which cases the task is
relatively simple.
- Those dead for a longer period, in which cases difficulty
is experienced due to pronounced stiffening of the fingers,
the early stages of decomposition, or both.
- Those cases in which extreme difficulty is encountered
because of maceration, desiccation, or advanced decay of the
skin.
These problems will be considered separately.
_1. Fingerprinting the Newly Dead._
When the fingers are flexible it is often possible to secure inked
fingerprint impressions of a deceased person through the regular
inking process on a standard fingerprint card. Experience has proved
that this task can be made easier if the deceased is laid face down
and palms down on a table (fig. 388).
In all cases where inked impressions are to be made, care should be
exercised to see that the fingers are clean and dry before inking. If
necessary, wash the digits with soap and water and dry thoroughly.
In the event difficulty is encountered in trying to procure
fingerprints by the regular method, it may prove more convenient to
cut the 10 "squares" numbered for the rolled impressions from a
fingerprint card. After the finger is inked, the square is rolled
around the finger without letting it slip. Extreme caution should be
exercised to see that each square bears the correct fingerprint
impression. After all the inked impressions are properly taken, the
ten squares bearing the impressions are pasted or stapled to a
standard fingerprint card in their proper positions, i.e., right
thumb, right index, right middle, etc. Whenever possible the "plain"
or "simultaneous" impressions should also be taken.
In some cases it will be found necessary to obtain or improvise a tool
similar to a broad-bladed putty knife or spatula to be used as an
inking instrument. The ink is rolled evenly and thinly on the knife or
spatula and applied to the finger by passing the inked knife or
spatula around it. The tool, of course, replaces the usual glass
inking slab or plate, the use of which is extremely difficult or
awkward when printing a deceased person.
_2. Fingerprinting the Dead, Where Stiffening of the Fingers and/or
Early Decomposition Are Present._
This second group consists of cases in which the hands of the deceased
are clenched, or the finger tips are wrinkled, or decomposition has
begun, and/or where there are combinations of these three conditions.
Cases of this sort may necessitate cutting off the skin. Legal
authority is necessary before cutting a corpse. Such authority may be
granted by state law or by an official having authority to grant such
a right.
[Illustration: 388]
In cases where rigor mortis (stiffening of the muscles) has set in and
the fingers are tightly clenched, the fingers may be forcibly
straightened by "breaking the rigor." This is done by holding the hand
of the deceased person firmly with one hand, grasping the finger to be
straightened with the four fingers of the other hand and placing the
thumb, which is used as a lever, on the knuckle of the finger and
forcing it straight (fig. 389). The inking tool and "squares," as
previously explained, are then used to secure the fingerprint.
In the event the rigor cannot be completely overcome, it will be most
helpful to improvise or secure a spoon-shaped tool for holding the cut
squares or cut strips while printing the fingers, similar to the tool
mentioned briefly in the discussion of crippled fingers. This tool,
somewhat resembling a gouge without the sharp edge, should have a
handle, a concave end, and a frame or clamp to hold the cardboard
squares or strips. In Figure 390, one type of tool is illustrated.
This tool eliminates the necessity of rolling the deceased's finger,
since the "square" assumes the concave shape of the tool, and the
gentle pressure applied to the inked finger when it is brought in
contact with the square results in a "rolled" impression without
actually rolling the finger.
[Illustration: 389]
Another problem encountered in this second group includes cases in
which the tips of the fingers are fairly pliable and intact, yet due
to the presence of wrinkles in the skin, complete impressions cannot
be obtained. This condition can be corrected by the injection of a
tissue builder, procurable from a dealer in undertaker's supplies. If
this is not available, glycerin or water may be used.
The method is simple. Injection of the tissue builder, glycerin, or
water, is accomplished by the use of a hypodermic syringe. The
hypodermic needle is injected at the joint of the finger up into the
tip of the finger, care being used to keep the needle below the skin
surface (fig. 391). The solution is injected until the finger "bulbs"
are rounded out, after which they are inked and printed.
Occasionally, in stubborn cases, entry of the needle at the joint and
injection of the fluid will not completely fill the finger bulb. It
may be necessary, therefore, to inject the fluid at other points of
the finger such as the extreme tip or sides, until suitable results
are achieved (fig. 392). The tissue builder has a distinct advantage
over glycerin or water, inasmuch as the builder hardens after a short
time and is not lost, whereas glycerin and water sometimes seep out
when pressure is applied in printing. To offset seepage at the point
where the hypodermic needle is injected, whenever possible, tie a
piece of string tightly around the finger just above the point of
entry of the needle.
When the tissue builder is purchased, a solvent for cleaning the
hypodermic syringe and needle should be acquired, inasmuch as the
builder will harden in the syringe and needle.
[Illustration: 390]
[Illustration: 391]
[Illustration: 392]
Those cases in which decomposition in its early stage is present
belong in this group also. Frequently, the outer layer of skin has
begun to peel from the fingers. A careful examination should be made
to determine if the peeling skin is intact or if a part of it has been
lost. If the skin is in one piece, an effort should be made to secure
prints just as though it were attached normally to the finger. Or, if
it is deemed advisable, the skin may be peeled off in one piece,
placed over the finger of the operator, and inked and printed as
though it were his own finger.
Occasionally the first layer of skin is missing. There remains the
dermis or second layer of skin which is also of value for
identification purposes. This second layer would be dealt with as
though it were the outside skin, using the techniques described above.
The ridge detail of the second layer of skin is less pronounced than
that of the outer skin, however, and more attention and care are
needed in order to obtain suitable impressions.
So far this discussion has dealt with the taking of impressions of
fingers when the flesh is fairly firm and the ridge detail intact. A
different problem arises when the fingers are in various stages of
decay. The techniques of treating the fingers in such cases vary
greatly, depending upon the condition of the fingers with respect to
decomposition, desiccation, or maceration.
_3. Fingerprinting the Dead in Difficult Cases._
In cases involving badly decomposed bodies the first thing to do is to
examine the fingers to see if all are present. If they are not, an
effort should be made to determine whether the missing finger or
fingers or even a hand was amputated during the person's lifetime, or
whether the loss was due to other causes such as destruction by animal
or marine life. Deductions from this examination should be noted on
the fingerprint record. This point is made in view of the fact that in
the fingerprint files of the FBI and some police departments, the
fingerprint cards reflecting amputations are filed separately. Noting
amputations may lessen to a great extent a search through the
fingerprint files.
In making the initial examination, attention should be given to the
removal of dirt, silt, grease and other foreign matter from the
fingers. Soap and water are good cleansing agents. So is xylene, a
chemical which will readily clean grease and fatty matter from the
fingers. Good results can be achieved by utilizing a child's
soft-bristled toothbrush in cases where the skin is fairly firm. The
brushing should be done lightly and the strokes should follow the
ridge design in order to clean not only the ridges but the depressions
as well. In the event that the skin is not firm enough to use the
toothbrush, a cotton swab may be used. The fingers should be wiped
very lightly with either soap and water or xylene, always following
the ridge contours.
At this point the fingers are again examined to determine the
condition they are in, based upon the circumstances in which the body
was found. Study and actual experience have shown that there are three
general types of conditions to be considered: Decomposition or
putrefaction, prevalent in bodies found in brush or buried in earth;
desiccation or mummification (that is, dried out), noted in bodies
which have been found in the open (ridge detail not in contact with
the ground) in dry protected places, or bodies subjected to severe
heat; and the group involving maceration (water soaking), which
ordinarily results from being immersed in water.
The degree of decomposition, desiccation, or maceration varies from a
comparatively early stage to an extremely advanced stage. Accordingly,
each case must be considered individually. For example, what is done
successfully in one case of desiccation may not show favorable results
in another. Hence, the techniques outlined below point out generally
what can be done, and has been done, with success.
[Illustration: 393]
When a body is found, the hands usually will be tightly clenched. The
first problem will be to straighten the fingers. If rigor mortis has
set in and an effort to straighten the fingers as previously explained
fails, the difficulty can be overcome easily. Using a scalpel, make a
deep cut at the second joint on the inner side of each of the four
fingers. They can now be straightened with the application of force
(fig. 393). The thumb, if it is cramped or bent, can generally be
straightened by making a deep cut between the thumb and the index
finger. These incisions are made for the obvious purpose of examining
the fingers to determine if there is any ridge detail. Before this
fact can be definitely ascertained it may be necessary to cleanse the
pattern areas with soap and water or xylene, as previously explained.
[Illustration: 394]
_Advanced decomposition_
If the case is one involving decomposition, the operator is confronted
with the problem of dealing with flesh which is rotted or putrefied.
The flesh may be soft or flabby and very fragile. If this is so, an
examination is made of the finger tips to see if the outer skin is
present. If the outer skin is present and intact, it may be possible,
using extreme care, to ink and print in the regular manner. Sometimes,
the outer skin, although present, will be too soft and fragile to ink
and roll in the regular way. In such cases, when the ridge detail is
discernible, the skin, if it is easily removed from the finger, or the
finger itself may be cut off at the second joint and placed in a 10-
to 15-percent solution of formaldehyde for approximately an hour to
harden it. Skin placed in a formaldehyde solution usually turns a
grayish white and becomes firm. However, it will be brittle and may
split if not handled carefully. The skin is placed in the solution
only until it hardens sufficiently, after which it is removed and
carefully wiped dry with a piece of cloth. Then the skin, placed over
the operator's own thumb or index finger and held in place by his
other hand, is inked and rolled as though the operator were printing
his own finger. If a legible print is not obtainable in this manner,
the operator should examine the underside of the skin.
[Illustration: 395]
In many instances, where the ridge detail on the outer surface has
been destroyed or is not discernible, the ridge detail is clearly
visible on the underside (fig. 394). If this is the case, the skin is
inverted (turned inside out) very carefully to prevent splitting or
breaking and then is inked and printed in the usual way. It must be
borne in mind, however, that when the underside of the skin is printed
the resulting impression will be in reverse color and position; that
is, the ink is actually adhering to what would be furrows of the
pattern when viewed from the proper or outer side. If it is deemed
inadvisable to try to invert or turn the skin inside out for fear of
damaging it, a photograph of the inner ridge detail is made and the
negative is printed to give an "as is" position photograph for proper
classification and comparison purposes. In order to secure good
photographs of the ridge detail it may be advisable to trim the skin,
flatten it out between two pieces of glass, and photograph it in that
position (fig. 395).
When the entire finger is placed in the solution during the hardening
process, the skin, in absorbing the formalin solution, may swell and
come loose from the finger. Should this occur, the skin must be
removed carefully and the procedure outlined above followed. If,
however, the skin still adheres to the finger and is not too wrinkled,
ink is applied and prints made. Should the skin be too wrinkled to
secure a satisfactory impression, consideration is given to the
injection of the tissue builder under the skin as previously
mentioned, in order to distend the pattern area. If successful, the
finger is inked and printed. This, of course, can be done only when
the skin is intact.
Should part of the skin be destroyed to the extent that tissue builder
cannot be injected effectively, while examination discloses that the
pattern area is present but wrinkled, cut off the entire pattern area
from the joint to the tip of the finger (fig. 396). Care must be
exercised to insure getting the complete fingerprint pattern as well
as cutting deep enough to avoid injury to the skin.
[Illustration: 396]
After excision, the flesh is carefully and meticulously removed from
the inside by scraping, cutting, and trimming until only the skin
remains, or until the specimen is so thin it can be flattened out to
remove most of the wrinkles. If the skin is fairly pliable, the
operator should attempt to place it over one of his own fingers and
try several prints. If the prints secured are not suitable, the piece
of skin (exert care to avoid breaking or splitting) is flattened out
between two pieces of glass and photographed (figs. 397, 398, 399).
[Illustration: 397. Inked print made from the finger of deceased
before treatment.]
[Illustration: 398. Inked print made after skin was removed and
treated.]
[Illustration: 399. Photograph of ridge detail of skin flattened
between two pieces of glass.]
The foregoing outline covers the procedures followed in cases
involving decomposition in which the outer skin is still present. In
many instances of decomposition the outer skin has been destroyed or
is in such a condition as to be of no value. It must be emphasized
again that the second layer of skin possesses the same ridge detail as
the outer layer and this, though finer and less pronounced, is just as
effective for identification purposes.
If, from examination, it is apparent that the outer layer of skin is
missing and the second layer is intact, the finger should be cleansed,
dried, inked, and printed in the usual manner. If the specimen is
wrinkled but pliable it may be possible to inject tissue builder, as
previously mentioned, to round out the finger, then ink and print it.
Occasionally, some of the outer skin is still attached but is of no
value. This skin should be removed by carefully picking or prying it
off with a scalpel in such a manner as not to destroy or injure the
ridge detail of the second layer. After the outer fragments have been
removed, the second layer is cleaned, inked, and printed. In the event
the resultant impressions are not suitable for classification and
identification purposes, the most likely reason for it is that the
ridge detail is too fine to print even though there are few if any
wrinkles in it. If this is the case, the finger should be cut off at
the second joint and photographed. Should wrinkles which cannot be
removed by injecting tissue builder, and which also preclude the
taking of suitable photographs, be present, the pattern area is cut
off with a scalpel from the first joint to the tip. The flesh is then
cut and scraped out as previously described, until the specimen is
thin enough to flatten out between two pieces of glass which may be
held together by scotch tape. The skin is then photographed.
Occasionally, even after the flattening process it will be noted in
the ground glass of the camera that the skin may be seen plainly but
the ridge detail is very poor. This difficulty may be due to the poor
contrast of the ridges and furrows when using direct lighting. If so,
it can be overcome by scraping the skin to transparency and then
photographing it by transmitted light (i.e., passing light through the
skin). Sometimes, due to the condition of the skin, even though it is
tissue thin, it will not be transparent. This can be overcome by
soaking the skin in xylene for a few minutes and then photographing it
by transmitted light while it is still impregnated with the xylene. If
the substance dries too fast to permit proper photographing, the skin
should be photographed while immersed in the xylene. (See subtopic of
this chapter pertaining to "general photography.") Of course, after
the skin has been photographed the negative should be printed to give
a reverse position so that the print will be comparable with inked
impressions on fingerprint cards.
_Desiccation and charring_
The problem confronting the fingerprint examiner in treating fingers
which are desiccated or dried and shriveled is that of distending and
softening the skin. Desiccated fingers are generally found to have the
outer layer of skin intact and the ridge detail fairly clear. However,
due to the shrinking, numerous wrinkles will be present, and as the
drying process continues the skin and flesh harden until the fingers
become almost as hard as stone.
It is sometimes possible to distend or swell the flesh by utilizing a
1- to 3-percent solution of sodium hydroxide or potassium hydroxide,
sometimes referred to as caustic potash. As a matter of caution, this
process should be tried with one finger before using it for the
remaining fingers. This point of caution is made because of the
reaction of the potassium or sodium hydroxide, which is actually one
of destruction. While absorption and swelling of the flesh occur, the
disintegrating action of the fluid may result in total destruction of
the flesh.
The finger to be distended is cut from the hand at the second joint
and placed in the hydroxide. When it has resumed its normal size by
the absorption of the solution, it is inked and printed. There is no
set time for this process. The procedure may require a few hours or as
much as several days until suitable results are obtained.
After the finger has been in the solution for about 30 minutes, it
should be removed and examined in order to note the extent of the
swelling and the reaction of the flesh to the solution. If no material
change is noted, the finger is returned to the solution. A close watch
is maintained and the finger is examined from time to time.
The solution may cause thin layers of skin to peel from the finger.
Should this occur, the loose skin is carefully scraped off and the
finger rinsed in water for a few minutes. It is then returned to the
hydroxide for continuation of the process.
If, during the course of an inspection, it is seen that the flesh is
becoming too soft, the finger should be placed in a 1- to 3-percent
solution of formaldehyde or alcohol for several minutes in order to
harden it.
If, after several hours in the hydroxide, the finger has not reached
its normal size, it should be placed in water for an hour or two. This
has a tendency to hasten the swelling. When the finger is removed, it
will be noted that a film has coated the surface. This coating is
carefully scraped off and the finger is replaced in the hydroxide
solution for an hour or so, again scraped if coated, soaked in clean
water, etc. This process of alternating from solution to water,
scraping, and replacing in hydroxide is continued until desirable
results are obtained. The finger is then inked and printed.
The above process will so saturate the finger with solution that it
may be too wet to print properly. Accordingly, the finger may be
dipped into acetone for several seconds, removed, and be permitted to
dry, after which it is inked and printed.
The complete process may take from several hours to as much as 10 days
to secure suitable results. If the final results of the above
procedure are satisfactory with the one finger being tested, the
remaining fingers are given the same treatment. Care must be taken to
identify each finger properly as to right index, right middle, etc.,
to avoid any mixup.
In the event that the reaction of the solution on the first finger
treated is not satisfactory and the operator feels that it would be
futile to continue the process, the finger should be removed from the
solution immediately, washed carefully in water, and placed in
formaldehyde to harden sufficiently for it to be handled without
causing injury to the ridges. The pattern area is cut off in such a
manner that sufficient surrounding surface permits the skin to be
trimmed. Then from the cut side the skin is carefully scraped and cut
to remove the excess flesh. While the cutting and scraping are being
done, from time to time the skin should be soaked in xylene and
massaged for purposes of softening to remove wrinkles. When the skin
is thin enough and sufficiently pliable, the operator places the skin
on his own finger, inks and prints it in the usual manner.
If the results are satisfactory, the same procedure is followed with
the remaining fingers. In the event the resultant inked prints are not
suitable, the skin should be scraped until it is sufficiently thin to
be flattened between two pieces of glass and photographed.
Here again it is pointed out that should there be a poor contrast
between the ridges and furrows when using direct lighting, the skin is
scraped as thin as possible without tearing and it is then
photographed by transmitted light.
There are also included, as cases of desiccation, bodies which have
been burned or subjected to severe heat. Often there are cases where
the skin has become loose but is hard and crisp, or where the finger
has been severely burned and is reduced almost to carbon, yet is firm.
In these instances the ridge detail usually has not been destroyed.
When a body which has been severely burned is located, the problems of
identification should be anticipated. Accordingly, before the body is
removed, a careful examination of the fingers should be made in order
to determine if the removal would, in any way, cause damage to the
fingers. Should it be felt that because of the condition of the body
removal would cause injury to the ridge detail, securing of
fingerprints at the scene, or possibly the cutting off of the hands or
fingers to avoid destruction of the skin, should be considered. An
examination of the fingers may disclose that the outer skin is
hardened and is partially loosened from the flesh. It is sometimes
possible, by twisting back and forth, to remove this outer skin
intact. If this is done, the operator may place the skin on his own
finger, ink and print in the usual way.
If the skin is intact on the finger and is not wrinkled, of course
there is no problem and the usual method is employed to secure
impressions.
Should wrinkles be present and the skin pliable, tissue builder is
injected into the bulbs, which are then inked and printed.
In the event the wrinkles cannot be removed in this fashion, the
pattern area is cut off and the excess flesh scraped out as before.
While the scraping and cutting are being accomplished, the skin should
be soaked and massaged in xylene to soften. The skin is then placed on
the operator's finger, inked and printed. Should prints made in this
manner be unsatisfactory, the next recourse is photography.
In some instances the fingers of burned bodies will be charred. Such
cases require very careful handling as there is a probability of
destroying or disturbing the ridge detail through mistreatment. In
these instances the procedure is determined by the degree of charring.
In extreme cases the only method of recording is by photographing,
using side lighting to secure the proper contrast of ridges and
depressions. Obviously, no attempt should be made to ink and roll as
the pressure necessary to secure the prints would cause the skin to
crumble.
In instances where the charring has not reached the extreme stage the
procedures previously set forth should be applied; that is, treatment
of the skin by cleaning, softening, inking and printing, or, finally,
by photographing (fig. 400).
[Illustration: 400. Photograph of charts used in actual case to
establish the identity of a charred body, victim of murder. Chart A
shows skin removed from one of the fingers treated and photographed.
Chart B shows an inked impression of the same finger during victim's
life.]
_Water-soaked fingers_
The third and final type of case which may confront the identification
officer concerns the problem of maceration, that is, long immersion of
the fingers in water.
One of the cardinal rules for securing legible impressions is that the
fingers must be dry. Accordingly, in these cases it becomes a matter
of drying the fingers in addition to contending with other
difficulties. Usually the skin on the fingers absorbs water, swells
and loosens from the flesh within a few hours after immersion.
If an examination discloses the skin to be water-soaked, wrinkled and
pliable, but intact, the first step is to cleanse the skin carefully
as previously described. Next, wipe the fingertip with alcohol,
benzine or acetone, waiting a few seconds for it to dry. The skin is
pulled or drawn tight across the pattern area so that a large wrinkle
is formed on the back of the finger, then the bulb is inked and
printed.
If the skin is broken and hanging loose, but its pattern area is
intact, it should be removed from the finger, cleansed and placed in
alcohol or benzine (not acetone) for about a minute, then stretched
carefully over the operator's finger so as to remove any wrinkles. It
may then be printed.
Sometimes the skin is intact on the finger but so wrinkled and hard
that it is not possible to draw it tight for inking. In this case it
may be advisable to inject tissue builder to round out the bulbs for
inking and printing. Should this fail, the ridge detail is
photographed on the finger; or the skin is cut off, flattened between
two pieces of glass and then photographed. Here, again, it must be
pointed out that when the ridge detail does not show on the surface of
the outer skin the underside should be examined, for many times the
detail can be seen clearly. Should this be true, of course, the
underside is photographed.
In cases where it is noted that the outer skin is gone and the finger
is not saturated with water, it is possible to dry the surface
sufficiently for inking and printing purposes by rolling the finger on
a blotter. If this fails, the finger is wiped off with a piece of
cloth which has been saturated with alcohol, benzine or acetone, after
which it may be inked and printed.
_Drying the fingers_
In many instances it will be found that the outer skin is gone and the
fingers themselves are saturated with water. A quick method of drying
out the fingers is to place them in full strength acetone for
approximately 30 minutes. The fingers are then placed in xylene for
about an hour or until the xylene has overcome the reaction of the
acetone. After removal from the xylene the fingers should be placed on
a blotter until the surface of the fingers appears dry. They are then
ready to be inked and printed.
It will be noted in this procedure that when the fingers are removed
from the acetone they dry and harden in a matter of seconds. The
purpose of the xylene is to resoften the fingers. After this
treatment, should the resulting inked impressions be unsuitable for
classification purposes, the ridge detail should be photographed.
_X-ray photography_
The use of X-ray photographs (radiography) has been advocated by some
for purposes of recording the ridge details in decomposed, desiccated,
or macerated cases. Briefly, the procedure involves the covering of
the fingers with heavy salts such as bismuth or lead carbonate, in a
thin, even film over the pattern area and then, by the use of the
X-ray, reproducing the ridge detail. This procedure necessitates the
use of X-ray equipment and a technician skilled in making radiographs.
It is, therefore, an expensive operation. The results of the
radiograph in no way compensate for the expense, time, and skill
required inasmuch as in those cases where many wrinkles and creases
appear in the fingers, especially desiccated specimens, the results
have been very poor. In instances where there are no wrinkles or only
a few, and where the creases are not too deep, the ridge detail is
reproduced very well in the radiograph. In these cases, however, it is
usually possible to secure impressions by inking and rolling in the
regular way or, should this fail, ordinary photography will certainly
give satisfactory results. For economical and practical purposes the
use of the X-ray is not recommended.
_General photography_
In the foregoing instances in which it has been impossible to obtain
suitable inked impressions it will be noted that the last resort has
always been photography. In all probability in advanced cases of
decomposition, desiccation, and maceration it may not be possible to
secure inked impressions which can be properly classified. Hence, it
will be necessary to photograph the ridge detail. Accordingly, there
are outlined below several methods of photographing the ridges which
have been used with success.
In photographing the ridge detail on fingers it has been determined to
be most practicable to photograph the finger natural, or 1/1, size
inasmuch as comparisons will usually be made with inked impressions
which are natural size. Any camera built or adjusted to taking 1/1
size pictures, and with which the lighting may be arranged to best
advantage, may be used.
There is a wide choice of film which can be used for this purpose. The
so-called soft films are all good for photographing ridge detail on
fingers. Process film is not recommended inasmuch as the film presents
too much of a contrast. Consequently, if it is used, some of the ridge
detail will be lost, especially if wrinkles are present in the skin.
Lighting is accomplished by the use of gooseneck lamps, floodlights,
or a spotlight. If a fingerprint camera is used, its lights may be
sufficient.
The manner of lighting may be by direct light, side light, transmitted
light or reflected light, depending upon the prevailing condition of
the finger or skin.
Direct light is used in those cases in which the ridge detail is
fairly clear and there are no wrinkles present; or, if wrinkles are
present, they are not deep enough to interfere with photographing the
ridges.
Side lighting is used when there are no wrinkles of any consequence
and the ridge detail is clear but because of discoloration the ridges
are not readily seen in the ground glass as there is lack of contrast
between ridges and depressions. Accordingly, the lights, instead of
being focused directly on the skin or finger, are placed to the side
of the object so that the light is directed across the skin or finger,
thus highlighting the ridges and shading the depressions.
In side lighting, two lights may be used. Better results are often
obtained, however, by using only one light, such as a spotlight, the
beam of which can be controlled to best advantage.
Transmitted light is used in cases in which the skin has peeled off or
in which the dermis has been removed, cut, and scraped thin so that
light will go through. The prepared skin is placed between two pieces
of glass pressed together in order to flatten the skin or dermis and
remove creases. By trimming some of the surplus skin or dermis,
especially at the top, it may be more easily flattened. After the
glass is properly mounted in front of the camera, the lights are
placed behind it and light is directed through the skin. The ridge
detail is brought into focus on the ground glass. Before the picture
is actually taken it is suggested that the ground glass be checked by
first using one light and then two lights to see which is more
effective.
There will be instances in which the second layer of skin, cut and
scraped thin enough to flatten out, fails when dry to have a
sufficient contrast between ridges and depressions for purposes of
photographing. The same piece of skin when soaked in xylene will show
a marked contrast, which it loses on drying. This difficulty is
overcome by photographing the skin while in solution, which can be
done by placing the skin in a test tube or a small bottle of a size to
keep the skin upright and the ridges toward the camera. The test tube
or bottle is then filled with xylene.
If the skin is sufficiently thin, transmitted light may be used.
Should it be found, however, that transmitted light is not effective,
then direct light may be tried and the results checked in the ground
glass (fig. 401).
When photographing a small curved surface such as a test tube, direct
lighting will usually create a high light. If the high light as shown
in the ground glass is over the ridge detail on the skin, a poor
photograph will result. If the high light cannot be removed by
rearranging the lights, then reflected light should be tried.
In order to effect reflected light a large piece of white paper,
cardboard, or similar material is used. A hole is cut in the center of
the paper or cardboard. This must be big enough for the camera lens to
protrude through. The ends of the paper or board are curved toward the
skin or finger to be photographed. The lamps which are to be used are
placed facing the curved paper or cardboard in such fashion that the
light will strike the paper or board and be reflected by the curved
surface to the object.
The lamps should be close enough to the paper or board to give the
maximum light. Care should be exercised, however, not to place them
too close, because of the fire hazard.
Any arrangement of lamps and reflectors giving a similar effect as the
above should prove suitable.
Fingers or skin which have a mottled, reddish-brown color because of
decomposition, exposure to severe heat, or diffusion with blood
present a problem of lack of contrast between ridges and depressions
for photographic purposes. This lack of contrast can be overcome to a
large extent by the use of a yellow or light red filter. Sometimes, in
those cases where the discoloration is due to the diffusion of blood
throughout the tissues, the blood can be washed out by saturating and
rinsing the specimen in a 10- to 20-percent solution of citric acid.
If, of course, the blood is not removed satisfactorily, the
photographing should be done with the filter.
[Illustration: 401]
As previously stated, the fingerprint camera can be readily adapted to
the use of photographing fingers or skin specimens for ridge detail.
Sometimes it is possible to photograph the skin or finger in the same
manner as one does a latent print. There will be instances, however,
in which the standard use of the fingerprint camera will not be
possible or effective, such as for side light, reflected light, and
sometimes transmitted light, or instances in which it is not possible
to get the finger or skin flush with the opening of the camera. In
these instances the lights of the camera are not used, so the
batteries should be removed and gooseneck lamps or other suitable
lighting equipment and ground glass utilized when the finger or skin
is prepared for photographing (fig. 402).
The camera is opened either at the point where the lights are housed
or at the lens point, whichever is most effective. Then, opening the
shutter, the operator moves the camera either toward or away from the
finger or skin to the point where the ridge detail is sharpest in the
ground glass. The camera is held firmly, the ground glass is removed,
the film is inserted and the photograph taken.
[Illustration: 402]
With respect to exposure time, it is possible only to generalize and
point out that each case will have its own individual aspects.
Controlling features for consideration will be the type of film, the
type and size of lights, the method of lighting (direct, side,
transmitted or reflected) and also whether or not filters are used.
Accordingly, there may be a wide variation of exposure time in
different cases.
The best approach for arriving at the proper exposure time is merely
to make a test exposure, develop the film, and from an examination
determine if it is underexposed or overexposed. Time the next exposure
accordingly, until satisfactory results are obtained.
As has been mentioned previously, when photographing the ridges on
fingers or skin, the ridge detail will be in reverse position, the
opposite from an inked impression made from the same skin or finger.
(This is true except in those cases in which the underside of the
epidermis is photographed.) Accordingly, when the negative is
printed, it should be printed gloss side to sensitive side of paper to
give the position comparable to an inked print made from the same skin
or finger. In order to avoid error or confusion a notation should be
made on the photograph of each finger, or, if they are cut and mounted
on a fingerprint card, point out that the position has been reversed
and that the prints are in their correct position for classifying and
searching. Otherwise, it is possible that the right hand may be
mistaken for the left hand and vice versa.
If the underside of the epidermis or outer skin is being photographed,
the negative should be printed in the normal manner, that is, emulsion
side of negative to sensitized side of paper. Here, reversal of
position is not necessary for when the ridge detail is viewed from the
underside it appears to be in the same position as the inked
impression normally is reflected on a fingerprint card.
Care should be taken to see that each photograph is labeled correctly
to indicate the finger it represents, such as right thumb, right
index, right ring, etc. It is imperative that no error occurs in such
labeling, inasmuch as it is highly probable that the resultant
classification would be incorrect and failure to make an
identification might very easily follow.
_Deceased infants_
The foregoing has dealt with the securing of fingerprints of unknown
deceased persons for identification purposes. The basis for such
action is the presumptive possibility that the unknowns had been
fingerprinted previously and through this medium might be identified.
Another type of problem, however, arises with the finding of a
deceased infant. It can be safely assumed that the possibility of
there being in existence a set of known fingerprints of the infant is
extremely remote. Nevertheless, in view of the fact that many
hospitals throughout the country, as part of the general routine of
recording a birth, secure the infant's footprints, it would follow
that there could be a remote possibility of identifying the deceased
infant through its footprints. The foregoing principles and procedures
would then apply in securing the foot impression of a deceased infant.
It is fully realized that in practically all cases involving the
finding of an abandoned infant corpse the infant is probably
illegitimate issue and delivery did not occur in a hospital, but there
have been instances where such was not the case.
The importance of securing footprints of deceased infants killed in a
common disaster cannot be overemphasized. Such disasters may involve
the death of infants of lawful issue, and in many instances there are
hospital footprint records available which may prove of value as a
positive means of identification.
_Technical consideration_
The methods described are intended to record, either by printing with
ink or by photographing as legibly as possible, the ridge details of
the tips of the fingers of unknown dead for identification purposes.
The securing of the impressions enables the fingerprint examiner to
classify and search them through a file. This "search," of course,
means merely to make a comparison of the deceased's prints with the
prints of known individuals.
It is well to bear in mind the fact that the dermis or epidermis may
have undergone certain physical changes and that in order for the
fingerprint examiner to make a proper comparison he must know the
changes which can and do occur. Otherwise, he may fail to make an
identification (fig. 403).
[Illustration: 403. Epidermis or outer layer of skin commencing to
peel from dermis or second layer of skin, result of decomposition.]
Consider first the epidermis or outer layer of skin in cases of
maceration (the skin is water soaked). There may be considerable
swelling. The ridges become broader and are more distinct. An inked
impression in such an instance may show a pattern larger in area than
a print made from the same finger when the person was alive. Also, if
the skin is on the finger but is loose, inking and rolling could
distort the impression so that some of the ridge formations would seem
to be in a different alignment from corresponding details in a print
made during life. When decomposition commences, what are really solid
ridges may be broken, giving rise to the possibility that there appear
to be more characteristics than there actually are (figs. 404 and
405).
[Illustration: 404. Inked fingerprint made during life.]
[Illustration: 405. Inked impression of same finger of deceased
showing effect of decomposition.]
The existence of wrinkles may also cause the impression to acquire an
appearance of dissimilarity when compared with the original inked
print.
With respect to cases of desiccation, there will probably be
shrinkage, hence, the impressions made may appear smaller than in life
and the ridges will be finer. In cases in which the epidermis has been
lost and there remains only the dermis or second layer, there will
usually be shrinkage with the same results. Here also, wrinkles, if
present, may cause a difference in appearance from the normal print.
[Illustration: 406]
In addition to shrinkage and wrinkles in cases involving the second
layer of skin, there is a radical change in the appearance of the
ridges themselves. The second or dermal layer of skin is composed of
what are called dermal papillae which have the appearance of minute
blunt pegs or nipples. The dermal papillae are arranged in double rows
(fig. 406). Each double row lies deep in a ridge of the surface or
epidermal layer and presents the same variations of ridge
characteristics as are on the outer layer of skin except that they are
double. Accordingly, when the second layer of skin is printed or
photographed, the ridge detail will appear in double. That is, the
ridges will appear as though they were split. This may well confuse
the fingerprint examiner in that what may be a loop having 10 ridge
counts may appear to be a loop having 20 ridge counts when the
impression is made from the second or dermal layer of skin. These
double rows of ridges are finer and not as sharp as the detail on the
outer skin, which adds to the difficulty of arriving at a correct
classification and making a proper comparison.
_FBI aid_
The above techniques and procedures have been dealt with upon the
basis that the law enforcement officers would, when a corpse has been
found, attempt to secure a set of finger impressions in an effort to
identify the unknown dead. If, however, the officer feels that the job
is too difficult or is beyond his scope, consideration should be given
to cutting off the hands or fingers of the deceased and forwarding
them to the Identification Division of the FBI for processing. If this
course is decided upon, it is reiterated that local statutes governing
the cutting of the dead must be complied with and proper authorization
must be secured.
[Illustration: 407]
In order to facilitate the transmission of such specimens to the FBI
the following suggestions are made:
First, it is deemed most desirable, when possible, to have both of the
hands, severed at the wrist, forwarded in their entirety (fig. 407).
It is desired that the hands, rather than each separate finger, be
sent inasmuch as it eliminates the possibility of getting the fingers
mixed up or incorrectly labeled. If, however, it is not possible to
send the hands for some reason, then, of course, the fingers should be
cut off and forwarded. In cutting, the fingers should be cut off at
the palm beginning with the right thumb, then the right index, ring,
etc., just as though they were to be printed. As soon as each finger
is cut off it should be placed in an individual container, such as a
small glass jar, and immediately marked as to which particular finger
it is.
In the event that the hands or fingers of more than one dead are being
transmitted, it is absolutely necessary that not only the fingers be
properly labeled but that each body also be given an identifying
number or symbol which must be indicated on the hands or fingers cut
from that body as well, in order to avoid the embarrassing situation
of identifying the hands and not knowing from which body they were
cut.
In shipping, the hands, fingers, or skins may be placed in preserving
solutions such as 5-percent solution of formaldehyde, 5-percent
solution of alcohol, or embalming fluid. When hands or fingers are
desiccated (dried out), however, it is most desirable that they be
placed in airtight containers and sent without any preservative. If
glass containers are used, the specimens should be packed in such a
manner as to avoid breakage. Dry ice is a suitable preservative for
transmitting such specimens but it should not be used when shipping
will take more than 24 hours.
In making up a package using dry ice, the hands or fingers, properly
tagged, should be placed in cellophane or paper bags. A material such
as sawdust, shavings or similar packing which acts as an insulation is
placed around the specimens. A sufficient amount of dry ice is then
placed in the package which is then packed tight with more sawdust or
shavings. The dry ice should not be in direct contact with the
cellophane or paper bags which contain the hands or fingers.
A letter covering transmittal of the specimens should be prepared in
duplicate. It should, of course, indicate the sender. The names of any
probable victims, sex, race and approximate age of the deceased
should, if such information is available, be secured from the coroner
or medical examiner and be included in the letter. A copy of the
letter should be placed in the package. The original should be mailed
separately. Both letter and package should be addressed as follows:
DIRECTOR
FEDERAL BUREAU OF INVESTIGATION
U.S. DEPARTMENT OF JUSTICE
WASHINGTON 25, D.C.
Attention: Identification Division--Latent Fingerprint Section.
If the package contains glass jars it should be marked "Fragile" to
insure careful handling in transit.
The package should be sent railway express, prepaid, or, where there
is need for speed, by air express, prepaid. When they are received by
the Identification Division, the specimens will undergo various
treatments which may necessitate further cutting, scraping, etc. In
all cases, regardless of condition, the specimens will be returned
after examination.
All of the foregoing matter has dealt with instances in which it has
been assumed that all ten fingers are available, or a sufficient
number of the fingers of a deceased have been secured and impressions
suitable for searching through the fingerprint files of the FBI have
been recorded.
There will be cases, however, where only a few, or possibly only one,
of the fingers has sufficient ridge detail for identification. In such
instances a search through the FBI files would be impractical. This,
however, does not preclude the possibility of making a positive
identification by the use of the one finger. Though a search through
the file is not possible, a comparison can be made with the
fingerprints of individuals who it is thought the deceased may be or,
in some instances, with the fingerprints of missing persons.
In this connection, where one or only a few fingers are forwarded to
the FBI, the names of all possible victims should also be submitted.
The fingerprints of those individuals, if available, will then be
taken out of file and compared with the ridge detail on the finger of
the deceased in an endeavor to establish a positive identification.
Many such identifications have been effected.
In conjunction with the usual services afforded authorized law
enforcement agencies, the services of an FBI fingerprint expert are
also made available in those cases where expert testimony is necessary
to establish the identity of the deceased through fingerprints,
providing, of course, such an identification has been made.
Extreme caution should be exercised in the case of the chemicals
previously mentioned in this article. Acetone, alcohol, benzine, and
xylene are highly inflammable and should neither be used near open
flames nor while the operator is smoking. The fumes given off by
acetone, benzine, xylene, and formaldehyde are toxic and may cause
sickness. They should be used in a well-ventilated room only. It is
also suggested that the fingerprint examiner wear rubber gloves when
using acetone, benzine, xylene, formaldehyde, potassium hydroxide, or
sodium hydroxide. These chemicals will cause the skin to peel. Strong
concentrations may cause burns.
In conclusion, it is pointed out that the procedures and techniques
which have been described are those currently being used by the
fingerprint experts of the FBI. These methods are fast and the results
have been most satisfactory. This Bureau does not claim, however, that
satisfactory results cannot be achieved through variations thereof or
different methods.
CHAPTER XI
_Establishment of a Local Fingerprint Identification Bureau_
For the information and assistance of officials who desire to
establish a local fingerprint identification bureau, the following
suggestions are being made to indicate the principal materials
necessary to equip such a bureau:
_Fingerprinting equipment_
For the purpose of taking fingerprints there should be a stand with a
clamp for holding the fingerprint cards steady. This latter item is
necessary to prevent smudging the prints. A tube of printer's ink is
used. The ink is applied by a roller to a glass plate upon which the
fingers are inked before being rolled on the cards. The complete
equipment for the above process may be secured from a number of
commercial sources or it can be made. Figure 408 depicts an inking
stand.
_Fingerprint files_
It is suggested that the fingerprint card be white, light cardboard, 8
by 8 inches, slightly glazed. This size is convenient, as it allows
all the space necessary for recording the classification of the prints
and general descriptive information concerning the individual. In the
event the new bureau desires to contribute copies of its fingerprints
to the Federal Bureau of Investigation, the latter will, upon request,
gladly furnish fingerprint cards for the purpose together with
envelopes and instructions on how to take fingerprints. It is
suggested that the new bureau design its cards similar to those
furnished by the Federal Bureau of Investigation, as these have been
designed after special study and have been found to be satisfactory
over a long period of time. Figures 409 and 410 show the fingerprint
side and reverse side of the criminal fingerprint card used by the
Federal Bureau of Investigation.
In classifying and comparing fingerprints it is necessary to use a
magnifying or fingerprint glass. Such instruments can be obtained from
various commercial sources. Figure 411 shows the type of magnifying
glass used by the Federal Bureau of Investigation.
[Illustration: 408. Diagram of a FINGERPRINT INKING STAND]
The fingerprint cards should be filed according to fingerprint
classification sequence in cabinets, preferably steel. It is further
suggested that the cabinets be three drawers high, with each drawer
divided into three rows for filing. Such cabinets or similar ones can
be obtained from various commercial sources. Figure 412 shows the type
of fingerprint cabinet used in the Federal Bureau of Investigation.
In order to facilitate the location of classification groups, it is
suggested that guide cards be placed in the rows of fingerprint cards
at frequent intervals. These guide cards should be slightly longer
and heavier than the fingerprint cards and should have small tabs on
the top to hold classification identifying symbols. Figure 413 shows
the type of guide card used by the Federal Bureau of Investigation.
[Illustration: 409]
LEAVE THIS SPACE BLANK |TYPE OR PRINT |SEX |RACE
| | |
|LAST NAME FIRST NAME MIDDLE NAME|--------|-----
| |HT. |WT.
| |(Inches)|
| | |
|----------------------------------|--------|-----
|CONTRIBUTOR AND |ALIASES |HAIR |EYES
|ADDRESS | | |
| | |--------------
-------------------------| | |DATE OF BIRTH
SIGNATURE OF PERSON | | |
FINGERPRINTED | | |--------------
| | |PLACE OF BIRTH
| | |
|-------------------------------------------------
-------------------------|YOUR NUMBER |LEAVE THIS SPACE BLANK
SCARS AND |AMPUTATION | |
MARKS | |------------------|CLASS
| |PLACE FBI NUMBER | -------------------------
-------------------------|HERE |
SIGNATURE OF DATE |------------------|REF.
OFFICIAL TAKING | _ CHECK IF NO | --------------------------
FINGERPRINTS ||_| REPLY |
| IS DESIRED |
---------------------------------------------------------------------------
1. RIGHT THUMB|2. RIGHT INDEX|3. RIGHT |4. RIGHT RING |5. RIGHT
| | MIDDLE | | LITTLE
| | | |
---------------------------------------------------------------------------
| | | |
---------------------------------------------------------------------------
1. LEFT THUMB |2. LEFT INDEX |3. LEFT MIDDLE|4. LEFT RING |5. LEFT LITTLE
| | | |
| | | |
---------------------------------------------------------------------------
| | | |
---------------------------------------------------------------------------
LEFT FOUR FINGERS TAKEN |LEFT |RIGHT |RIGHT FOUR FINGERS TAKEN
SIMULTANEOUSLY |THUMB |THUMB |SIMULTANEOUSLY
| | |
| | |
| | |
| | |
A practice which has been of the utmost benefit in the Federal Bureau
of Investigation is as follows: When a fingerprint card is taken out
of its regular file for any reason, a substitute card is put in its
place, to remain until the return of the card. This substitute card,
or "charge-out" card, is of a different color from the fingerprint
card and slightly longer. On it are recorded the name, the
classification formula, and peculiar characteristics, such as scars
and peculiar pattern formations, appearing on the original card. By
indicating the date and reason for charging out the original card, the
Bureau is able to keep an accurate check on the whereabouts of all
prints at all times. It is suggested that the local bureaus adopt a
practice of this kind whenever a fingerprint card is drawn from the
files and it is known that it may be out for a period of time longer
than the remainder of the day on which it is drawn. Figure 414 shows
the type of charge-out card used in the FBI.
[Illustration: 410]
FEDERAL BUREAU OF INVESTIGATIONS, UNITED STATES DEPARTMENT OF JUSTICE
WASHINGTON, D.C.
--------------------------------------------------------------------------
CURRENT ARREST OR RECEIPT
--------------------------------------------------------------------------
DATE ARRESTED | CHARGE OR OFFENCE |DISPOSITION OF SENTENCE
OR RECEIVED |(If code citation is used |(List final disposition only.
|it should be accompanied by|If not now available
|charge) |submit later on FBI Form R-54
| |for completion of record.)
| |
| |
---------------|---------------------------|
OCCUPATION |RESIDENCE OF PERSON |
|FINGERPRINTED |
| |
-------------------------------------------|
If COLLECT wire reply or COLLECT telephone |
reply is desired, indicate here |
_ _ |
|_| Wire reply |_| Telephone reply |
| FOR INSTITUTIONS USE ONLY
---------------- |
Telephone number | Sentence expires____________
-------------------------------------------|------------------------------
| INSTRUCTIONS
|1. FORWARD ARREST CARDS TO FBI
| IMMEDIATELY AFTER
| FINGERPRINTING FOR MOST
| EFFECTIVE SERVICE.
|
|2. TYPE or PRINT all
| information.
|
|3. Note amputations in proper
| finger squares.
|
Please Paste Photograph in This Space |4. REPLY WILL QUOTE ONLY
| NUMBER APPEARING IN THE
Since photograph may become detached | BLOCK MARKED "CONTRIBUTOR'S
indicate name, FBI number, and arrest | NO."
number on reverse side whether attached to |
fingerprint card or submitted later. |5. Indicate any additional
| copies for other agencies
| in space below--include
| their complete mailing
| address.
-------------------------------------------|------------------------------
| SEND COPY TO:
|
|
|
|
--------------------------------------------------------------------------
FD-249
Each fingerprint card handled by the bureau should receive a
fingerprint number and these numbers can be assigned in consecutive
order.
As the bureau increases in size, it will be found a source of much
convenience to have fingerprints of males and females kept in separate
files.
_Name files_
There will be times when it may be necessary to locate an individual's
fingerprints when no current fingerprints are available, but the name
with a police number or the classification is known. In order to
facilitate work of this nature, as well as to keep a complete record
and check on each set of fingerprints, it is necessary that the files
be indexed in a manner similar to that in which books in a library are
indexed.
[Illustration: 411]
[Illustration: 412]
In this connection, for each fingerprint card there is prepared an
index card. On this the name of the individual is placed, with all
known aliases, the fingerprint classification formula, the police or
arrest number, the date of arrest or other action. It is desirable,
also, to have on this card such general information as age, height,
weight and race. Figure 415 shows the front of a suggested type of 3-
by 5-inch index card.
[Illustration: 413]
[Illustration: 414]
| | | | | | |
| | | | | | |
| | | | | |FBI NUMBER |Followed
+--------+--------+----------+----------+-------+-------------+
|ASSEMBLY| POST G | N-IDENTS | DOC. LAB | MISC. | |
+--------+--------+----------+----------+-------+ |
|Searched Thru|
+-------------+
................................. Classification....................
MASTER PRINT NAME
................................. Reference.........................
CURRENT PRINT NAME
+--------------+--------------+---------------+-------------+-------------+
|1. Right Thumb|2. Right Index|3. Right Middle|4. Right Ring|5. Right |
| | | | |Little |
| | | | | |
| | | | | |
+--------------+--------------+---------------+-------------+-------------+
|6. Left Thumb |7. Left Index |8. Left Middle |9. Left Ring |10. Left |
| | | | |Little |
| | | | | |
| | | | | |
+--------------+--------------+---------------+-------------+-------------+
TYPE OF CURRENT PRINT |Number and Initials of
Criminal | Non-Criminal |Employee Charging Out:
| |
Date..................|Date...................|............................
16-58188-1 U.S. GOVERNMENT PRINTING OFFICE
Figure 416 shows the reverse side of the 3- by 5-inch index card.
These are filed alphabetically in special cabinets. An index card also
should be made for every alias which an individual has used. Figure
417 shows an electrically operated file cabinet in which the index
cards are filed. It is suggested that the alias cards be of a
different color from the one bearing the correct name, known as the
"Master." Each alias card also should have typed on it the correct
name of the individual, for purposes of reference and cross-checking.
For convenience and accuracy these files, as in the fingerprint files,
should also have suitable guide cards.
[Illustration: 415]
| |
______________________________________________|______________|____________
LAST NAME FIRST NAME MIDDLE NAME | F.P. CLASS | IDENT NO.
| | |
______________________________________________|______|_______|____________
ALIAS RACE SEX AGE
__________________________________________________________________________
ADDRESS | | | | |
| | | | |
__________|__________|________|________|______________|___________________
HEIGHT WEIGHT EYES HAIR COMPLEXION OCCUPATION
|
______________________________________|___________________________________
DATE AND PLACE OF BIRTH SCARS AND MARKS
__________________________________________________________________________
(SEE OTHER SIDE FOR ARREST RECORD)
[Illustration: 416]
DATE | NUMBER | CHARGE | DISPOSITION
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
______|__________|__________|_________________
| | |
It is advisable to make use of charge-out cards when original index
cards are drawn from the files. Figure 418 shows a charge-out card.
To supplant the 3- by 5-inch index cards mentioned above, many law
enforcement agencies have found it desirable to use a separate sheet,
sometimes referred to as a "History Sheet" or "Information Sheet,"
containing the complete case history of the subject involved. These
separate sheets can be filed by fingerprint number sequence and
contain not only the data such as the known aliases, the fingerprint
classification formula, the arrest number, and other essential items
which are set out on the 3- by 5-inch cards as heretofore described,
but also contain a concise summary of the subject's arrest history,
particularly with reference to his criminal activities in the
particular city. They may also contain a summarized case history with
respect to each arrest or commitment, including such items as the date
and place of arrest, complete home address, relatives, the essential
facts concerning the prosecution of charges, and the ultimate
disposition.
[Illustration: 417]
_Jacket folder file_
When an identification bureau receives prints of individuals on whom
it already has prints, it is not practical to keep more than one set
of prints per person in what may be called the active fingerprint
file. In these instances the better print should be designated a
"Master" print by having the word "Master" stamped thereon. It should
be given a number, to be known as the master number, which number
should also be placed on all other sets of prints which may be found
to be identical with the "Master" print. The "Master" print is placed
in the active files. The extra prints are placed together in a heavy
folder with their master number stamped thereon. This jacket folder is
then filed in a separate cabinet. Also, if copies of all information
regarding an individual, photographs, and FBI transcript of record are
kept in this folder, his complete record will always be assembled in
an easily accessible unit. The "Master" number should also be placed
on the index card and all the alias cards of the individual. Also,
each new alias and arrest number should be placed on the original
index card. The additional records are kept in folders which are
arranged in numerical order, beginning with Nos. 1, 2, 3, and so on.
[Illustration: 418]
1-154 |-----------| | GPO: 1962 OF--663475
| | |
|-----------| |-------------------------
| | | POSTING
|-----------| |-------------------------
| | |
| | |DOB
-------------------------|-----------|-----------|-------------------------
| ASSEMBLY | MISC. | DESCRIPTION
---------------------------------------------------------------------------
NAME_____________________________________________________
__________________________________________________
NAME______________________________________________
___________________________________________________________________________
(ARREST NUMBER) (DEPARTMENT) (CITY) (STATE)
A further suggestion in connection with the maintenance of this folder
file, besides the use of a separate "Master" numbering system, is the
use of the arrest fingerprint number. As indicated previously, each
person arrested and fingerprinted is assigned a number. This number
appears on the fingerprint card, name-index card, and photograph. The
practice of handling every new arrest fingerprint card in the bureau
should include searching the fingerprint card in the fingerprint file
to ascertain if the subject has a previous record. If the subject does
not have a previous record, a new number should be assigned. In this
connection it is noted that only one copy of the fingerprint card
should be maintained in the file by fingerprint classification. To
indicate the new arrest on the old index card, the date of the new
arrest can be shown. Whether the bureau follows the "Master" numbering
system or the "previous arrest" numbering system should make very
little difference in the ultimate purpose. All extra copies of
fingerprint cards, complete record sheets, photographs, and all
information pertaining to the individual are filed away in the folder
file. This complete record is readily accessible at all times. It will
now be found that the bureau has a complete record of each individual
who has an arrest record on file, with provision made for accurate
cross-referencing and checking between names and fingerprints.
_Dispositions_
It is important to the bureau to have complete information concerning
the ultimate disposition on each arrest fingerprint card. If the
disposition of a charge is known at the time the person is
fingerprinted, this fact should be indicated in the space provided on
the fingerprint card. For example, in the case of an individual who is
arrested, fingerprinted, and turned over to the county jail, this
disposition can be indicated on the fingerprint card which is
forwarded to the Federal Bureau of Investigation. The fingerprint card
should not be held by the bureau pending final disposition of the
charge.
In those cases where the disposition is pending prosecutive or court
action, a separate 3- by 5-inch disposition file can be maintained. On
these cards information concerning the name, fingerprint number, race,
sex, charge, name of the arresting officers, and the fingerprint
classification should appear. These cards are filed in a
pending-disposition file. The 3- by 5-inch disposition cards are made
at the time the fingerprints of the person are taken. When the final
disposition is obtained it should be noted on the card. In those cases
where there is only one fingerprint card in the bureau, the
disposition can be noted on the name-index card or the reverse side of
the bureau's fingerprint card. In those cases where there is a
jacket-folder file for the individual this disposition card can then
be placed in the folder.
"Disposition Sheets" (No. R-84) can be obtained from the Federal
Bureau of Investigation for forwarding this information so that the
files of the FBI will have complete information concerning the
arrests. At the time the final disposition is obtained, these
disposition sheets can be completed and forwarded to the Federal
Bureau of Investigation.
_Death notices_
When persons whose fingerprints are on file are reported as deceased,
the prints should be taken from the active file and assembled with
any other prints of the person concerned. These should be plainly
marked "Dead" and filed in a separate cabinet or section. All the
index cards on this individual should also be marked "Dead" and filed
in a separate section. These should be retained for possible future
reference.
In this connection, "Death Notice" forms (No. R-88) can be obtained
from the Federal Bureau of Investigation so that information
concerning these deaths can be properly noted in its fingerprint file.
_Record of additional arrest_
It is not necessary for a bureau to send a regular fingerprint card to
the Identification Division of the Federal Bureau of Investigation on
individuals who have been arrested repeatedly and whose previous
records are known to the local law enforcement agency. In such cases
the "Record of Additional Arrest" form should be used.
Complete information must be given on this form. It is imperative that
the FBI number and the finger impressions be placed on this form. The
Identification Division of the Federal Bureau of Investigation will
send no answer upon receipt of this form.
The form will be placed in the FBI number folder on the individual and
later when a regular fingerprint card is received the arrest
information from all the forms will be compiled and included on the
subject's record as "supported by fingerprints."
"Record of Additional Arrest" forms (No. 1-1) can be obtained from the
Federal Bureau of Investigation.
_Wanted notices_
All wanted notices containing fingerprints, including the wanted
notices inserted in the FBI Law Enforcement Bulletin, should be filed
in the fingerprint file by classification formula, and the names
appearing on these wanted notices should be indexed and placed in the
name files. Concerning the small wanted notices inserted in the FBI
Law Enforcement Bulletin, a suggested procedure would be to paste each
individual notice on a blank 8- by 8-inch white card. The wanted
notices are filed by the fingerprint classification and the names
indexed and placed in the name file. When an apprehension notice is
received concerning the wanted notice, a proper notation should be
made on the name card and the wanted notice in the fingerprint file.
If these canceled wanted notices endanger the efficiency of the file,
it is suggested that the name-index card and the fingerprint-wanted
notice be destroyed. Should the bureau adopt this practice it is
suggested that the 8- by 8-inch cards be used again for other wanted
notices. In this manner it would be possible to use the blank card for
eight of these notices.
The Federal Bureau of Investigation will make available to law
enforcement agencies a special "Wanted Notice" form (No. 1-12) in
order that they can place wanted notices against the fingerprints in
the files of the FBI.
_Photographs_
Arrangements should be made to procure a camera for taking photographs
of the persons fingerprinted. This is known as a "mugging" camera and
various types are on the market. It is believed that the photographs
should include a front and side view of the person. In most instances
a scale for indicating height can be made a part of the picture even
though only the upper portion of the individual photographed is taken.
Of course, if the scale is used, the person photographed should be
standing even though only the upper portion of the body appears in the
photograph. The necessary lights should be provided for obtaining
photographs. A standard set of scales should be obtained in order that
the correct weight can be ascertained.
[Illustration: 419]
The negatives and photographs can be filed by fingerprint number in a
separate file. In those cases where the individual has more than one
arrest all the photographs can be placed in the jacket-folder number
file. The negatives, in these instances, can remain in the photograph
file.
_Latent fingerprints_
To adequately develop the latent prints at crime scenes, it is
necessary that the proper equipment be provided. This equipment
includes latent fingerprint powders, brushes, lifting tape,
fingerprint camera, searchlight, and scissors. All of this equipment
can be obtained from commercial fingerprint supply companies. Figure
419 shows some of the equipment used by the FBI. The techniques of
developing latent fingerprints and their uses are more fully explained
in the following chapters.
It is believed that by following the basic ideas outlined, the
officials of law enforcement agencies can be assured of best results
in establishing and maintaining a small identification bureau. For
further information, the Federal Bureau of Investigation will furnish
to duly constituted law enforcement officials any additional data
which may be of material assistance in the maintenance of such a
bureau.
CHAPTER XII
_Latent Impressions_
Each ridge of the fingers, palms, and soles bears a row of sweat pores
which in the average person constantly exude perspiration. Also, the
ridges of the fingers and palms are in intermittent contact with other
parts of the body, such as the hair and face, and with various
objects, which may leave a film of grease or moisture on the ridges.
In touching an object, the film of moisture and/or grease may be
transferred to the object, thus leaving an outline of the ridges of
the fingers or palm thereon. This print is called a latent impression,
the word "latent" meaning hidden, that is, the print many times is not
readily visible.
Latent impressions, regardless of the area of the ridges present, are
of the greatest importance to the criminal investigator as
identification of them may solve the crime and result in successful
prosecution of the subject. Consequently, every effort should be made
to preserve and _identify_ them.
Visible prints in mediums such as blood, grease, dirt, or dust are
equally important to the investigator but, strictly speaking, are not
latent impressions.
A search of the crime scene should be conducted in a logical manner.
Points of entry and exit should be examined, along with surfaces or
objects disturbed or likely touched during the commission of the
crime. The examiner should wear a pair of light cloth gloves and
handle an object only insofar as is necessary and then only by edges
or surfaces which are not receptive to latent impressions. A record of
the exact location of a print on an object and of the object itself
should be made, since these facts may be of the utmost importance in
any trial resulting from the investigation. No one should handle an
object other than the examiner himself.
Portable articles removed should be labeled or marked so that they may
be readily identified thereafter.
The beam of a flashlight played over the surface of an object will
frequently show the location of latent impressions, although this is
not an infallible test for their presence.
Evidence should be examined as soon as feasible after its discovery.
Following the location of any latent prints at the scene of a crime,
the prints of all persons whose presence at the place under inspection
has been for legitimate purposes must be excluded from further
attention. It is advisable, therefore, during the initial stages of an
investigation where latent prints are found, to secure the inked
prints of all members of the household, the employees, and any police
or other officials who may have touched the objects on which the
latent impressions were found. Inked prints taken for this purpose are
referred to as elimination prints.
Due to the fragmentary nature of most latent prints it is not possible
to derive a classification which makes a file search practicable. A
latent impression may be identified, however, by comparison with the
prints of a particular suspect.
Inked fingerprints taken for comparison with latent impressions should
be as legible and as complete as possible, including the areas not
essential to classification, since identifications are often made with
these areas. Inked palm prints taken should likewise be complete and
clear and should include impressions of the finger joints. Persons not
experienced in latent print comparisons should not attempt to evaluate
latent fragments, since the area necessary for an identification may
be extremely small compared to that of an average inked fingerprint.
Articles which are to be transported by mail or express should be so
packed that the surfaces bearing latent impressions are not in contact
with other surfaces. This may be accomplished by mounting the articles
on a piece of fiber board or plywood. The board should then be secured
in a box so that the objects will not touch or be shaken against the
sides in transit. The package should be plainly marked "Evidence," to
prevent inadvertent handling on opening. Cotton or cloth should never
be placed in direct contact with any surface bearing latent prints.
Any number of paper or cardboard specimens may be placed in a single
protective wrapper, since contact with other surfaces does not harm
latents on such objects. Lifts, negatives and photographs are readily
enclosed with letters.
An explanatory letter should accompany all evidence. If it is
necessary to pack the evidence separately, a copy of the letter should
be placed in every package so that the recipient will know immediately
the import of the contents. All items of evidence should be marked and
described exactly in the accompanying letter so that they will not be
confused with packing material of a similar nature, and to provide a
check on what the package should contain.
In addition, the letter should include for record purposes a brief
outline of the crime, i.e., type, date and place of occurrence, and
names of victims and subjects. If suspects are named for comparison,
sufficient descriptive data should be set out to permit location of
their fingerprint records. This information, in preferential order,
comprises the individual's complete name, aliases, FBI number, date of
prior arrest or fingerprinting, fingerprint classification, date and
place of birth, and physical description.
Evidence is preferably forwarded by registered mail or railway
express, as these means provide records of dispatch and receipt.
Elimination or suspect fingerprints are best enclosed with the
evidence itself, with a notation as to the type of prints forwarded.
CHAPTER XIII
_Powdering and Lifting Latent Impressions_
The sole purpose in "developing" a latent impression is to make it
visible so that it may be preserved and compared. Various powders and
chemicals are used for this purpose. When a latent print is plainly
visible, it should be photographed before any effort is made to
develop it.
No attempt should be made to brush or apply powder to prints in dust,
obviously greasy prints, or bloody prints, as this will almost surely
destroy them. Objects which have been wet or immersed in water may
still bear identifiable latent impressions. Before any examination is
attempted, however, the object must be dried.
Powder brushed lightly over a latent-bearing surface will cling to
grease or moisture in the ridges of a latent print, making it visible
against the background. Obviously, a powder should be used which will
contrast with the color of the surface. Photographic contrasts should
also be considered.
A gray powder and a black powder are adequate for latent print work.
Many fingerprint powders of various colors and compositions are
available from fingerprint supply houses but none are superior to the
gray and black.
A very small amount of powder is placed on the brush for application
to the surface. Once the contour of a print is visible, the brush
strokes should conform to the direction of the ridges. All excess
powder should be brushed from between the ridges. Too much powder and
too little brushing are the chief faults of beginners.
Gray powder is used on dark-colored surfaces. It is also used on
mirrors and metal surfaces which have been polished to a mirrorlike
finish, since these surfaces will photograph black with the
fingerprint camera.
Black powder should be applied to white or light-colored surfaces.
Aluminum powder affords the same contrast as the gray. Gold and red
bronze powders, although of a glittering appearance, will photograph
dark and should consequently be used on light-colored surfaces.
Dragon's blood powder is a photographically neutral powder and may be
dusted on either a light or dark surface.
On clear transparent glass, either gray or black powder may be used,
it being necessary only to use a contrasting black or white background
when photographing.
Prints should be lifted after photographing. Both rubber and
transparent tape are available for this purpose. Rubber lifting tape
is procurable in black or white 4" x 9" sheets and has the adhesive
surface protected with a celluloid cover. A black powder print should
obviously be lifted on white tape and a gray powder print on black
tape.
Gold bronze and red bronze powders should be lifted on white tape,
aluminum on black. Dragon's blood may be lifted on either black or
white.
After cutting a piece of tape sufficiently large to cover the entire
latent print, the celluloid covering is removed and the adhesive side
applied to the latent. The tape should be pressed evenly and firmly to
the surface, taking care not to shift its position. It is then peeled
gently from the surface and the piece of celluloid placed over the
print to protect it. The operator should handle the lift in such a
manner that he will leave no prints of his own on the adhesive
surface. A small paper identification tag bearing the initials of the
operator, date, and object from which lifted should be placed under
one corner of the celluloid, or this information may be written on the
back of the lift itself if it can be done in a permanent, legible
manner.
If an excessive amount of powder adheres to the latent print, a more
legible print may sometimes be obtained by lifting a second time (on a
new piece of tape, of course).
It should be noted that a print lifted on rubber tape is in a reverse
position. Consequently, in preparing a photograph of a print on such a
lift, it will be necessary to print the negative from the reverse side
in order for the print to appear in its correct position for
comparison. Preparation of such photographs should not be attempted by
persons of inadequate knowledge and experience.
Transparent tape with a durable adhesive surface is available in 1" to
2" widths for fingerprint work. The common variety of transparent tape
is not suitable due to the deterioration (drying) of the adhesive
surface. The print on a piece of transparent tape is in correct
position. Transparent lifts should be affixed to a smooth, grainless,
opaque background of a black or white color contrasting with the
powder used. Every effort should be made to avoid air bubbles under
such lifts. In no instance should a transparent lift ever be folded
back on itself or stuck to another piece of such tape as a backing,
since it is generally not possible to determine the correct position
of such a print.
Groups of latent impressions, such as those of adjacent fingers or
fingers and palms which appear to have been made simultaneously,
should be lifted as units, that is, on a single piece of tape, as this
may facilitate the task of making comparisons.
CHAPTER XIV
_Chemical Development of Latent Impressions_
Chemical treatment in the development of latent finger impressions on
paper, cardboard, and newly finished or unpainted wood may involve a
slightly more complicated technique than that in which powders are
utilized, but the results justify the additional effort.
It is very strongly recommended that powders not be applied to
articles of the above types. This recommendation is made for several
reasons. First, powders cannot be removed from paper and possibly may
interfere with some types of document examinations. In this
connection, they are likely to prevent restoration of the specimen to
a legible condition. Powders will not develop as many latent
impressions as chemicals on paper or cardboard. In some cases they
will obscure latent impressions subsequently developed chemically.
Neither scientific training nor complete knowledge of the chemical
processes involved is necessary for one to become proficient in the
use of chemical developers, two of which will be discussed more fully.
These two, iodine and silver nitrate, are the most commonly used,
inasmuch as they are relatively inexpensive, readily procurable,
effective, and easy to apply.
All specimens which are treated should be handled with tweezers or
gloves.
When iodine crystals are subjected to a slight amount of heat they
vaporize rapidly, producing violet fumes. These fumes are absorbed by
fatty or oily matter with which they come in contact. If the specimen
treated bears latent impressions which contain oil or fat, the print
is developed or made visible by the absorption of the iodine fumes and
the ridges of the print appear yellowish-brown against the background.
Iodine prints are not permanent and begin to fade once the fuming is
stopped. It is necessary, therefore, for the operator to have a camera
ready to photograph the prints immediately.
Control of the fumes is achieved by using the crystals in an iodine
gun or fuming cabinet. The iodine gun may be assembled by the
individual examiner, by a druggist, or it may be purchased through a
fingerprint supply house.
Material for making the iodine gun, as well as iodine crystals, may be
procured from a chemical supply house or through a druggist. The gun
itself consists essentially of two parts. One tube (the end of the gun
through which the breath is blown) contains a drying agent such as
calcium chloride, to remove moisture from the breath. Without this,
the moisture from the breath and saliva would condense at the end of
the gun, drip onto the specimen and cause stains which might prove
indelible. The second tube contains a small amount of iodine crystals
which are vaporized by the heat of the breath, augmented by the warmth
of the hand cupped around the tube containing the iodine. This vapor
is blown onto the specimen (fig. 420). Glass wool serves to hold the
calcium chloride and iodine in place.
[Illustration: 420. Iodine fuming gun in use.]
Due to the amount of physical exertion involved, the gun is generally
limited to the examination of a few small specimens. Where a large
number of specimens are to be treated, the fuming cabinet, a
box-shaped wooden receptacle with a glass front and top permitting the
operator to control the amount of fumes in the cabinet and observe the
development of the latent impressions, is used (fig. 421). The fumes
are generated by placing a small alcohol burner under an evaporating
dish containing the iodine crystals. This is set in a hole cut in the
bottom of the cabinet. As soon as the fumes begin to appear in
sufficient amounts, the burner is removed. The specimens may be hung
in the cabinet by wooden clothes pins fastened to a removable stick
which is supported by wooden strips affixed near the top edges of the
cabinet. The top of the cabinet is removable to permit access.
Diagrams for the construction of the iodine gun or fuming cabinet will
be furnished on request to members of the law enforcement profession.
Many specimens bear small, greasy areas which, in addition to any
latent impressions of a greasy nature, will also appear
yellowish-brown after exposure to iodine fumes. All these stains will
eventually disappear if the specimen is placed in a current of air
from a fan or vent. All latent impressions on an object will not be
developed by the iodine process but only those containing fat or oil.
Due to this fact and the fact that iodine evaporates from the surface,
it is used prior to (it cannot be used afterward), and in conjunction
with, the silver nitrate process.
[Illustration: 421. Iodine fuming cabinet in use.]
No ill effects have been noted from contact with small amounts of
iodine vapor but prolonged or excessive contact will produce
irritation of the skin and respiratory passages. To prevent gradual
loss of the chemical through evaporation and the corrosion of
surrounding metal surfaces, iodine crystals should be kept in an
airtight container when not being used.
The development of latent impressions with silver nitrate is dependent
on the fact that the sodium chloride (the same substance as common
table salt) present in the perspiration which forms the ridges in most
latent impressions reacts with the silver nitrate solution to form
silver chloride. Silver chloride is white but is unstable on exposure
to light and breaks down into its components, silver and chlorine. The
ridges of the fingerprints developed in this manner appear
reddish-brown against the background. Immersion in the silver nitrate
solution will wash traces of fat and oil from the paper;
consequently, it is necessary to fume the specimen for latents of such
a nature prior to treatment with silver nitrate.
Once the requisite equipment is assembled, the steps in the process
are these:
Dip the specimen in the solution, blot and dry it, expose to light,
and photograph latents when contrast is good.
Chemically standardized solutions are not required for the successful
application of this process. It has been determined through long
practice that a 3-percent solution of silver nitrate is adequate for
the purpose, although concentrations up to 10 percent are sometimes
used. A solution of approximately 3 percent may be prepared by
dissolving 4 ounces of silver nitrate in 1 gallon of distilled water.
Smaller quantities of 3-percent solution are made by using the
components in the same proportion. For instance, one quart of water
will require 1 ounce of the crystals. For a 10-percent solution, use
13-1/3 ounces of crystals per gallon.
An alcohol solution may be preferred. This is prepared by mixing 4
ounces of silver nitrate crystals, 4 ounces of distilled water, and 1
gallon of grain alcohol, 190 proof. The alcoholic solution dries
faster, and when treating paper bearing writing in ink, it is less
likely to cause the ink to run. On the other hand, the alcoholic
solution is much more expensive and there is some loss by evaporation
while in use.
The solutions may be used several times before losing their strength
and when not in use should be kept in brown bottles in cupboards to
retard deterioration. If the strength of the solution is doubtful, the
operator should attempt to develop test latent impressions before
proceeding on evidence.
Silver nitrate crystals and distilled water in small amounts are
obtainable from druggists or in large amounts from chemical supply
houses. Dealers in distilled water are located in many communities.
Tap water should not be used in the preparation of the solution
because it generally contains chemicals which will partially
neutralize the silver nitrate.
It is suggested that the solution be placed in a glass or enamelware
tray approximately 18 by 12 by 5 inches for use, a size used in
photographic development. Treatment with this solution is called
"silvering." The specimen is immersed in the solution so that the
surfaces are completely moistened, then taken out, placed between
blotters to remove the excess solution, and dried. The drying is
readily accomplished with an electric hair dryer. Blotters may be
dried and used several times before discarding. It is not necessary to
work in a dark room. Work in an illuminated room but not in direct
sunlight. Soaking the specimen in the solution does not aid
development and is actually undesirable as it requires a longer drying
time. The specimen should be reasonably dry before exposing to the
light, otherwise the latent prints may be developed while the paper
is still wet, thus necessitating drying in subdued light to prevent
darkening.
Development of the latent impressions occurs rapidly when the specimen
is exposed to a blue or violet light source. A 1,000-watt blue or
daylight photographer's lamp, a mercury arc (most ultraviolet lamps
are of this type), or carbon arc is excellent for the purpose (fig.
422). If a weaker light is used, a stronger mixture of the solution
should be prepared. For instance, if a 300-watt bulb is used, the
10-percent solution would be preferable. Direct sunlight will cause
the latent impressions to appear very rapidly and if several specimens
are exposed at once it is not possible for a single operator to
properly control the development. Sunlight coming through a window
pane will serve for development. Where fingerprints containing sodium
chloride (normally exuded from the sweat pores in the ridges) have
been deposited, the silver chloride formed will darken against the
background.
[Illustration: 422. Developing silver nitrate prints using 1,000-watt
bulb reflector.]
As soon as the ridge detail of the prints is clearly visible, the
paper should be removed from the light. Continued exposure will darken
the paper and the contrast will be lost.
Paper so treated should be kept in darkness; that is, in a heavy
envelope or drawer until ready to photograph.
Immediate photographing, as in the case of iodine prints, is not
always essential, since the prints are permanent and become illegible
only through eventual clouding of the background. Prompt photographing
is recommended, however, as, in exceptional instances, silver-nitrate
prints have become illegible in a matter of hours. Darkening
ordinarily will occur slowly if the paper is preserved in absolute
darkness, and silver-nitrate prints so preserved more than 10 years
have been observed to be quite clear.
Items such as cardboard cartons, newspapers, road maps, large pieces
of wrapping paper, or smooth, unpainted wood surfaces, too large for
dipping, may be treated by brushing the solution over the surface with
a paint brush (fig. 423). Brushing does not damage or destroy latent
impressions on surfaces of this type. Cardboard boxes may be slit down
the edges and flattened out to permit easy placement under the light.
[Illustration: 423. Silver nitrate solution being applied with paint
brush.]
Wet paper should be handled with extreme care to prevent tearing. In
treating very thin types of paper the solution is best applied with a
cotton swab or brush.
Photographs, Photostats, and blueprints of any value should not be
treated with silver nitrate, since the developed prints or stains
cannot be removed without destroying them.
In working with silver nitrate, wear rubber gloves or handle all
specimens with tweezers; avoid spilling it on clothing. It will cause
dark brown stains on clothing, skin, and fingernails. Such stains are
not easily removed. Areas of the skin subjected to prolonged contact
are deadened, will turn black and peel.
If removal of silver nitrate prints (called "de-silvering") is
desired, this may be accomplished by placing the specimen in a
2-percent solution of mercuric nitrate in a tray similar to that used
for the silver nitrate.
To prepare a small amount of this solution, dissolve two-thirds of an
ounce of mercuric nitrate crystals in 1 quart of distilled water and
add one-third of a fluid ounce of nitric acid. Shake well. This
solution, too, may be used several times before losing its strength
and is not necessarily discarded after each use. It is not necessary
to keep it in a dark bottle.
The specimen bearing silver nitrate prints is immersed in this
solution until all traces of the prints disappear. It should then be
rinsed thoroughly in water to remove all mercuric nitrate. If this is
not done the paper deteriorates, becoming brittle and crumbly. A tray
of distilled water may be used for rinsing or a tray of ordinary tap
water changed several times during the rinsing. The specimen is then
laid out flat to dry.
Wrinkles, such as are left in paper after ordinary drying, may be
prevented by ironing with a moderately hot iron. An electric iron with
a temperature control is desirable. If kept too hot it will scorch or
wrinkle the paper somewhat. The bottom of the iron should be clean so
that unremovable smudges will not be left on the paper.
No ill effects have been noted from working in the 2-percent mercuric
nitrate solution with bare hands for very short periods, but it is a
caustic solution and it is suggested that the specimens be handled
with tweezers or that rubber gloves be worn if contact is prolonged.
CHAPTER XV
_The Use of the Fingerprint Camera_
If a fingerprint is visible, an effort should be made to photograph it
before any attempt is made to develop it. In every case a print
developed with powder should be photographed before lifting. It
sometimes happens that the print does not lift properly although it
may be quite clear after development.
The camera which is especially adapted to the purpose and which is
easiest to handle and operate is the fingerprint camera, one type of
which is shown in figure 424. This camera has several advantages in
photographing fingerprints:
It photographs the prints in natural size.
It contains its own light source.
It has a fixed focus.
Cameras of this type are available in models operated by batteries and
110-volt current. It is believed that the battery-operated type has
the greater utility, since house current may not be available at the
crime scene. When not in use the batteries should be removed as they
will eventually deteriorate and corrode the brass contacts in the
camera.
[Illustration: 424. The fingerprint camera.]
The camera is of the box type and has three button controls which will
open: (1) The metal flap covering the aperture, (2) the front portion
of the frame providing access to the self-contained light bulbs, and
(3) the camera in half, providing access to the batteries and the
shutter as shown below in figure 425.
[Illustration: 425. Button controls permit access to bulbs, batteries,
and shutter.]
A 2-1/4 x 3-1/4 film pack adapter or a 2-1/4 x 3-1/4 cut film holder
holds the film in the camera. The film pack adapter will hold a pack
of 12 sheets of film, and accordingly, will permit the taking of 12
pictures. The cut film holder is a unit which holds two sheets of film
utilizing each side of the holder.
It is pointed out that the FBI uses the film pack exclusively in view
of the fact that practically all latent examinations will necessitate
the taking of more than two pictures. Further, the film pack is made
so that it may be loaded into the adapter in the open light. Also, the
films are numbered 1 through 12, which is a valuable feature in that
in maintaining notes concerning the latent examinations it is a simple
matter to note by the number of the negative where the latent
impression was developed and photographed. Should it happen that
during a latent examination all twelve of the films are not used, the
film pack, with the slide in place, is taken into the darkroom and
only those films which have been exposed are removed and developed.
The unexposed films remain in the film pack adapter with the slide in
and may be used later.
As was previously mentioned, the camera has a fixed focus; that is,
the camera will take a legible picture only when the latent print is
at the focal point, or exactly flush with the opening of the camera.
The latent print must not be inside the open end of the camera, nor
must it be beyond; otherwise, the picture will be blurred.
[Illustration: 426. When object being photographed does not cover
camera opening, outside light is excluded with piece of cloth.]
Since the camera has its own light source, any leakage of outside
light will cause overexposure of the film. Consequently, if the
surface of the object bearing the latent print which is to be
photographed is uneven or does not cover the entire front of the
camera opening, it will be necessary to use some opaque material such
as a focusing cloth or heavy dark material to cover the front of the
camera so as to exclude all outside light (fig. 426). If a latent
print on a pane of glass or an automobile window is being
photographed, it will be necessary to back up the latent so that there
will be no light leakage. Material showing a pattern or grain should
not be used for this purpose as any such pattern will photograph in
the background and possibly obliterate the ridges of the latent print.
To insure an equal distribution of the light over the latents being
photographed, the impressions should be centered in the opening of the
camera. This is accomplished by opening the angular front section of
the camera after the metal plate covering the front has been opened,
and setting the aperture over the latent impressions so that they will
be as near the center as possible. Then, holding the camera firmly in
place, it is carefully closed (fig. 427).
During exposure the camera must be held perfectly still. Any movement
of the camera or object will result in a fuzzy or double image.
In photographing a small, movable object such as a bottle or tumbler,
the camera should not be placed on its end and an attempt made to
balance the object across the opening. Instead, the camera should be
placed on its side and the bottle or tumbler built up to the opening
so that there is no necessity for holding the object (fig. 428). There
will be, of course, instances where the camera will have to be held,
such as to the side of a wall, cabinet or automobile. Here an extreme
effort should be made to avoid moving the camera or permitting it to
slip during exposure.
[Illustration: 427. Centering of latent in aperture insures equal
distribution of light over print.]
Anticipating the possible use of the photographic negatives in a court
proceeding, it becomes of paramount importance to be able to identify
them. This is done by using what is called an identification tag. The
tag consists of a small piece of paper bearing the date, initials of
the examiner, and possibly a case number, and it should be
hand-written. The tag is placed near the latent prints being
photographed so that it will appear in the picture. It should be borne
in mind that concentration should be on the latent impressions, which
must be centered, and the identification tag should be to one side and
not covering any of the latent prints. Another method of
identification, if the surface permits, is to write the
above-mentioned data on the surface of the object bearing the latents
so that the information set out will also be a part of the picture.
Too much emphasis cannot be placed on the importance of the
identification tag. The lack of such data, by discretion of the
court, may exclude the latents as evidence, in the absence of the
original specimen bearing the latents.
[Illustration: 428. In photographing objects with curved or irregular
surfaces, camera should be laid flat and latent-bearing surface built
up to opening.]
The following are suggested exposure times for Tri-X film (available
in 2-1/4" x 3-1/4" film packs) with battery-operated cameras having
lenses without diaphragms:
Black powder print on white or light background--snapshot
Gray or white powder print on black or dark background--1 second
These same exposure times can be used on some cameras having lenses
with diaphragms, provided the lens opening is set at f6.3.
The above exposure times are for cameras with batteries in average
condition. If batteries become weak the exposures may be increased
slightly.
In making snapshots the shutter mechanism should be manipulated as
rapidly as possible since slow motion will appreciably lengthen the
exposure. In making time exposures the camera shutter must be held
open for the desired time. Personnel with photographic experience may
desire to use cut film with the fingerprint camera. A few tests will
determine the optimum exposure times for any particular type of film.
Briefly, the procedure for taking photographs of latents is as
follows: The film pack is placed into the film pack adapter with the
safety paper side of the film pack to the slide side of the adapter,
care being taken to see that all of the paper tabs are outside of the
adapter. The adapter is placed on the camera in its proper position by
opening a slide clamp attached to the camera, fitting the side of the
adapter into the slot away from the clamp and pushing it down flat
into the opening. Don't try to slide the adapter into the opening from
the top. The adapter is locked in position by closing the clamp. Next
the slide is removed and the tab marked "Safety Cover" pulled out as
far as it will come and torn off. The camera is placed in position and
the first exposure made; then the tab marked "1" is pulled and the
next film is in position for exposure. This procedure is followed with
each succeeding film until all have been exposed.
When the last tab has been pulled out, the pack can be removed from
the adapter in daylight. If all of the films have not been exposed the
slide is replaced into the adapter and the film pack removed from it
in a darkroom, as previously stated.
As a matter of regular policy, it is recommended that more than one
exposure be made of each latent, varying the normal exposure time to
insure satisfactory results, especially when the contrast is not a
good black on white or gray on black.
Before starting to photograph, note the following:
- Check shutter action.
- Check bulbs, batteries, and lights.
- Center latents in opening of camera.
- Latent being photographed must be flush with opening of
camera.
- Outside light must be excluded.
- Include identification tag in photograph.
- Remove slide and pull safety tab of film pack before
making exposure.
- Hold camera still while making exposure.
- Pull correct number tab after each exposure (be careful
not to pull more than one).
- Do not use grained or uneven material as a backing when
photographing latents on transparent glass.
- Mirrors, polished chrome, and nickel plate will photograph
black in the fingerprint camera.
The foregoing has dealt with the standard use of the fingerprint
camera when the direct light afforded by the camera gives suitable
results. There will be cases, however, where the results from the use
of the direct light may not be adequate. Such cases may involve molded
or embedded prints, such as prints in putty, wax, soap, etc. Should
direct light give poor results, side lighting may prove effective.
This can be done by loosening two of the bulbs on one side so that
they will not light. The light given by the other two bulbs is
directed so as to pass at right angles, as much as possible, across
the ridges of the embedded latent print. Adjustment of the exposure
time must be made when this is done.
CHAPTER XVI
_Preparation of Fingerprint Charts for Court Testimony_
In testifying to fingerprint identification, the expert often prepares
charts to visually aid the court and jury in understanding the nature
of his testimony. Many times it is undoubtedly difficult for the
layman to perceive, from a vocal explanation alone, the full import of
an expert's testimony, due to its technical nature; consequently, some
graphic representation of the facts presented is amply justified and
rewarded. The preparation of the charts is ultimately the sole
responsibility of the expert using them. As a matter of interest to
law enforcement personnel engaged in fingerprint work, a brief
explanation of the preparation of such charts follows, along with
suggestions and remarks based on long experience in these matters.
To do the work conveniently, it will be necessary to have available,
in addition to the ordinary photographic developing and printing
materials, a projection enlarger which will enlarge preferably to at
least ten diameters. In the projection method of enlargement, the
image is printed directly from the original negative, and the
preparation of an enlarged negative is unnecessary.
Aside from the photographic equipment, the needed materials are: a
roll of scotch photographic tape 1 inch wide to outline the areas of
the fingerprints on the negatives to be used; some stiff cardboard
approximately 1/32 inch thick on which to mount the prepared charts; a
tube of rubber cement; and a bottle of translucent ink, other than
black or white.
A light-box on which to view the negatives while blocking, and a
lettering set to draw the lines and numbers uniformly on the charts,
while not absolutely essential, are helpful conveniences. A light-box
is basically a frosted pane of glass with a light beneath it to
produce soft, even, non-glaring illumination. If no light-box is
available, a clear window may be utilized in "blocking" the negatives.
If the expert finds it necessary to have an outside source prepare his
photographs, he should retain personal custody of the evidence during
the operation.
The original latent print and inked print with which it is identical
should be photographed actual size. This procedure eliminates
guesswork in enlarging both to the same degree. Whatever areas of the
two prints are deemed requisite to illustrate the method of
identification are then outlined (blocked) on the negatives with the
masking tape, so that only those areas will show in the subsequent
enlargements. Generally, if the legible area of the latent print is
small, it is well to show the complete print. If the area is large,
however, as in a palm print, an area which will not make the chart too
bulky or unwieldy may be selected.
In blocking, the negative is affixed to the window pane or light-box
by means of strips of photographic tape across the corners, with the
side to be blocked up. This prevents constant shifting of the negative
while it is being prepared. The latent print should be blocked first.
Corners of the blocked areas should be square. Care should be
exercised to have as nearly as possible the same ridge formations
shown and the ridge formations in the same upright or horizontal
positions. This may be facilitated by fixing a negative, bearing ruled
squares, between the negative being blocked and the glass to which it
is attached.
If the latent print was developed or photographed as a light print on
a dark background, a reverse-color negative should be prepared and
blocked in order that both prints may appear as black ridges on light
backgrounds. This is done by placing the original negative adjacent to
a new sheet of film and exposing it. The resultant negative contains
the same image as the original except that the color of the image has
been reversed.
If the negative is a photograph of an opaque lift, the print appears
in reverse position; that is, as a mirror image, and the negative will
accordingly have to be blocked from the dull or emulsion side in order
for it to appear in a position comparable to that of the inked print.
Failure to present the prints in question in the same color and
position may possibly confuse the observer and nullify the purpose for
which the chart is made.
The degree of enlargement is not important in itself, so long as the
ridges of the latent print are readily distinguishable by the eye. Ten
diameters have been found adequate, although any enlargement from 5 to
30 will serve. It should be remembered, however, that small
enlargements are difficult to see a few feet away and that large ones
lose some of the contrast between ridges and background. A white
border of at least 1-1/2 inches or a width equal to about one-third
the enlarged area should be left for charting purposes.
Any chart prepared must be technically correct; that is, the
corresponding ridge characteristics in the two prints must be
similarly numbered and indicated.
Several ways of pointing out the similar ridge formations have been
observed, but the one which appears soundest is also simplest and
consists of merely marking the characteristics with lines and numbers.
All of the ridge characteristics in the prints need not be charted.
Twelve characteristics are ample to illustrate an identification, but
it is neither claimed nor implied that this number is required.
All fingerprint identifications are made by observing that two
impressions have ridge characteristics of similar shapes which occupy
the same relative positions in the patterns.
Methods involving superimposition of the prints are not recommended
because such a procedure is possible only in a very few instances, due
to the distortion of ridges in most prints through pressure and
twisting. Such a procedure is not necessarily a test of identity.
Likewise, presenting charts with the shapes of the characteristics
drawn in the margin is not recommended. Individual ridge
characteristics may vary slightly in actual shape or physical position
due to twisting, pressure, incomplete inking, condition of latent
print when developed, powder adhering to background, etc.
Identifications are based on a number of characteristics viewed in a
unit relationship and not on the microscopic appearances of single
characteristics.
Since the enlarged photographs appear in black and white, an ink other
than black or white should be used to line the chart. Such an ink
should be preferably translucent so that it will be possible to see
the ridges which it traverses. A translucent carmine drawing ink
serves well. In placing the lines on the chart, they should be
arranged so that they do not cross or touch.
The chart will present a clearer, neater, and more pleasing appearance
if it is numbered clockwise and the numbers are evenly spaced (fig.
429). It is not necessary, however, to place the numbers evenly around
the photograph.
[Illustration: 429. Chart illustrating method of fingerprint
identification.]
Ordinarily, the numbers are placed on three sides and the type of
print (latent or ink) noted at the bottom. In any case, the manner of
numbering should be subservient to an explanation of the
characteristics in an orderly sequence; and, if the situation warrants
it, all of the points may be illustrated on a single side of the
photograph.
A single line should be drawn from each characteristic to a numbered
point on the margin. Care should be taken to draw the line exactly to
the characteristic point, not short of it, beyond it, or obscuring it.
Erasures should be avoided. If the ink runs or blots, it is sometimes
possible to remove it with a cloth dampened in denatured alcohol,
without damaging the photograph.
If the enlargement is great, that is, 25 or 30 diameters, it might be
well to draw a small circle around each characteristic and then draw
the line from the circle to the number, since the ridge will be much
thicker than the illustrating line. All lines and numbers should be
checked for absolute accuracy. The expert should also study the
enlargements for _apparent discrepancies_ in the prints, which he
might be called upon to explain.
The charted enlargements are readily mounted on stiff cardboard with
rubber cement, which may be purchased in small tubes. After cementing
the photograph to the cardboard, it should be placed under a heavy
flat object which will cover the entire surface until dry to prevent
warping and wrinkling. After drying, trim the two enlargements to the
same square size with heavy scissors, a pen knife or scalpel, and
fasten them together, book-fashion, with strips of the photographic
tape used in blocking the negatives. Of course, if charts are large,
20 to 36 inches square, mounting is unnecessary and they will have to
be supported in the courtroom with thumbtacks or metal rings.
Some courts do not permit numbering or lining of the photographs and
the enlargements alone in these cases will have to suffice. If there
is some question about admissibility of the charted enlargements, it
is well to prepare an extra uncharted set.
CHAPTER XVII
_Unidentified Latent Fingerprint File_
From time to time the FBI is requested to conduct surveys and
participate in conferences and in police schools on the problem of
fingerprint identification.
As a result of its observations in the course of these activities it
has been found that many identification bureaus are not fully aware of
the importance which latent finger impressions can have in connection
with the ordinary handling of arrest fingerprint cards.
Many bureaus and departments spend considerable time in developing
latent impressions in a particular case. If no immediate results are
forthcoming, the latent impressions are filed for future reference.
Single fingerprint files have been maintained with success by some
departments. Many others do not attempt to keep a file because of
either limited personnel or lack of funds. In many departments,
however, where such a file is maintained, too often latent impressions
are simply filed with no regard to possible future use. Actually,
these impressions should be treated as evidence directly connecting
the subject with the crime.
Active consideration should be given to the latent impressions until
they are identified or the case has been successfully prosecuted. It
is definitely felt that the following suggested procedure might have
some decided advantages.
It is suggested that in all cases where latent impressions are
developed at the crime scene, or on an object used in connection with
the commission of a crime, the impressions be properly photographed
and lifted. The evidence, where possible and practicable, should be
properly packed, labeled, and stored for future use in court (fig.
430).
Use care in wrapping the evidence to see that the latent impressions
on the objects are not destroyed. If the specimens are later used in
court, the impressions should still be clearly visible. In the same
manner, all evidence not of a bulky nature, such as photographic
negatives, photographs, and lifts of latent impressions, should be
similarly preserved for future court use. It is to be emphasized that
all material in one case should bear a case number. All specimens not
of a bulky nature can be placed in an envelope and filed by this case
number (fig. 431).
The above procedure is the usual one followed by the majority of
identification bureaus in handling latent impressions. In order,
however, to keep the latents in an active state, the photographs of
all the latent impressions found in a particular case should be cut up
and pasted on a 3 by 5 card bearing the case number and title of the
case (fig. 432).
[Illustration: 430. Evidence labeled and latents protected for storing
for future court use.]
[Illustration: 431. Latent material in a case should be filed under a
single case number.]
If numerous latents are developed, several cards should be used, all
having the same number and title. These cards are then filed by case
number in a regular filing cabinet. Before this step is taken, every
effort should be made to secure and compare the fingerprints of
individuals who may legitimately have placed their prints on the
objects which were examined. In addition, as part of the case report
bearing the same case number as the latent impressions, there should
be a notation pointing out that latent impressions were developed in
the case and that they are on file.
[Illustration: 432. For ready current comparisons latents in a case
are placed on a 3 x 5 card bearing case title and number.]
Case #2345
Unknown Subjects
Jones' Drug Co.
B&E
3-15-47
Fingerprint comparisons in this unidentified file can be made on the
basis of fingerprints taken from day to day of individuals
fingerprinted for criminal identification purposes. A routine may be
set up whereby the fingerprints of individuals arrested each day will
be compared the following day with the latent fingerprints filed in
the unidentified latent file. It is most important that this procedure
be rigidly followed from day to day. It is to be borne in mind that
the comparisons are made whether the particular person is or is not a
suspect in a certain case. Special attention should be paid to
fingerprints of individuals charged with burglary, breaking and
entering, armed robbery, and other similar crimes.
Should an identification be made of some latent prints, and others in
the same case remain unidentified, the 3 by 5 card should remain in
file until the case is fully closed, inasmuch as more than one person
may be involved in the crime. Of course, if all the latents are
identified, then the 3 by 5 card is removed and placed with the
negatives, lifts, etc.
It may be deemed advisable to remove these latents from the file in
instances where the statute of limitations covering the crime has run.
If the above procedure is rigidly followed, identification in many
instances will result--more than would be effected if the department
maintained only a single fingerprint file in which the latent prints
were merely filed away. Very often such a latent fingerprint file is a
source of information when all logical investigative leads have been
exhausted.
_This résumé of latent impressions has been prepared by the
Federal Bureau of Investigation in the belief that it may be
of possible interest to law enforcement officers desiring to
avail themselves of latent identification evidence in
connection with their investigative activities. It should be
borne in mind that the comments and expressions set out in
this book are not intended to convey the thought that the
Federal Bureau of Investigation believes the points
emphasized are the only ones of moment, or that other
methods of developing latent impressions are not equally
acceptable. The Federal Bureau of Investigation will be glad
to answer any questions on the foregoing which may occur to
any law enforcement officer who reads this material._
*** End of this LibraryBlog Digital Book "The Science of Fingerprints - Classification and Uses" ***
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