Examination of Firearms Review: 2007 to 2010 - Interpol

2.4.2 Case reports
Bresson and Franck (76) report on a long distance shooting for which they
determined the shooting distance in a somewhat particular way. In their
experiment they fired bullets at different velocities to a concrete plate. The bullet
damage was consequently compared to the damage observed on the crime
scene bullet. The damage was quantified by length and diameter. The velocity
that was calculated from these experiments was used to extrapolate to the
shooting distance. The greatest degree of uncertainty in this method arises from
the lack of information of the muzzle velocity. Hu et al. present a case report
where SEM/EDX was used to reconstruct the shooting trajectory. It demonstrates
the evidential value of trace analysis (77).
2.4.3 Trace analysis
Wehner et al. (78) have investigated the possibility of associating bullets found at
the crime scene to specific trajectories in the body of a gunshot victim. They
investigate heart- and liver-specific cell material on the bullets. The method is
particularly useful in the case of expanding bullets where the insides of those
bullets can be swabbed.
Goddard et al. use advanced methods to examine latent fingerprints on brass
surfaces (79). As brass is a very common material in ammunition, this can be of
interest. Atomic Force Microscopy (AFM) is used to visualize corrosion of the
metal on a nanometre scale. The method shows in detail the corrosion
mechanism between the fingerprint deposit and the metal after heat treatment of
the latter. Also Bond has done quite some work on fingerprint evidence. In a
publication he goes into depth on the visualization of latent fingerprint corrosion
of metallic surfaces (80). It was established that the salts in the fingerprint
residue corrode the metal surface to produce an image of the fingerprint that is
both durable and resistant to cleaning of the metal. The author proposes a heat
treatment to enhance the durability of the fingerprint. Also cartridge cases need
to be heated additionally after discharge. The return, however, is low as cartridge
cases tend to lose some of the fingerprint evidence during loading and ejection.
For these types of evidence, the author suggests an electrostatic enhancement
technique so the conducting powder adheres better to the corroded areas. The
same author has continued this work in another publication (81). Here is
presented a case report in which the author recovers an old latent fingerprint on
a brass cartridge case. It demonstrates that novel techniques can visualize
fingerprints where cyanoacrylate fuming can fail to do so. Edmiston and Johnson
propose an optimal sequence for chemical development of latent prints on
cartridge casings and shotgun shells (82).
Gashi et al. have examined, using infrared video evidence, the temperature
developed during discharge of 9 mm cartridge cases (83). It was concluded that
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