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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 v
lume of prints it has become necessary to

extend the normal classification formula.

To illustrate this point:



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


Key Major Primary Secondary Subsecondary Final

6 17 aW IIO 9


Key Primary Small letter Subsecondary Final


8 S 1 Ua II 6


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


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.