Examination of Firearms Review: 2007 to 2010 - Interpol

The use of heat (using a hair drier and tweezers) to remove self-adhesive stamps
from an envelope was used to further process the sticky side of the stamp but also
the paper underneath the stamp (418). The use of Wetwop on the stamp gave no
results, but the processing of the envelope with ninhydrin led to the detection of a
mark lying initially beneath the stamp. It then appeared that the mark was transferred
from the stamp (after it had touched the palm of the suspect) to the paper, giving a
mirror image of the print.
Three cases related to the detection of fingermarks on foldable or torn substrates
have been reported (419). In one case, folding the ninhydrin-processed substrate
allowed to join two fingermark halves, that was subsequently inserted as a whole in
an AFIS search. In a second case, a torn paper sheet was reassembled to infer the
cutting dynamics performed by the suspect. The last case was about the transfer of
secretion residue that occurred between two paper substrates put in contact, which
led to the detection of a pair of mirrored fingermarks.
The report of a bank robbery for which the suspect entered the bank from the roof,
through the attic, down to a back room was made (420). When dusting the floor,
using black powder to detect footmarks, the author found a very well-defined
handmark (palm and fingers) left on the floor when the suspect supposedly crawled
around the room.
Four case reports were related with corpses' identification. First, latex has been used
to obtain a negative copy of damaged fingertips belonging to corpses in a bad state
of preservation (e.g., mummy and carbonization) (421). Fingertips were first brushed
with ether to remove the grease from the skin, before a thin layer (ca. 0.5 mm) of
liquid latex was spread on the finger using a wooden rounded rod. Once dried (ca.
after 10 minutes), the latex film was removed and placed over a finger-shaped
support previously soaked in latex, to be finally used in a fingerprinting identification
procedure (e.g., inked or photographed). It should be recalled that the record
constitutes a negative picture of the original print, and will have to be reversed in
colour and shape before using it for identification. The only restriction imposed by the
latex technique is that the mummified or charred fingertip must not be previously
treated with sodium hydroxide, because it prevents the rubber from vulcanizing. A
second case reported the use of black powder on the skin (i.e., fingertips and palms)
detached from a cadaver in bad state of conservation (422). The use of black powder
had for effect to darken the ridges and to create a visual contrast enabling the
photography of the skin, and its use as reference material. This solution has been
chosen because an inking process would have caused detrimental effects on the
fragile skin. Finally, the identification of 60-year-old mummified remains (i.e., forearm
and hand) using fingerprints and DNA was reported (423). Fingertips were
rejuvenated by rehydration, before being moulded with silicone rubber, then casted to
create positive impressions of each fingertip. The identification of a badly
decomposed body is the subject of (424). A possible name of the deceased was
available, and ten-print records of this person were on file. One of these ten-print
records showed clear pore details in the palmprints. Only three level II characteristics
were found to be in agreement, however, a lot of pore detail was visible on both
impressions and allowed the identification. In a further approach, the skin was
cleaned, and three more minutiae could be matched to characteristics present on the
exemplar.
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