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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 ou
er 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.

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.

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


[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.