Gunshot Wounds: Visual and Analytical Procedures

Abstract

In most instances of death from gunshot wounds, the forensic pathologist is readily able to determine whether or not a particular gunshot wound was inflicted at contact, intermediate, or distant range. In some instances, however, such a determination is virtually impossible. Most difficulty occurs in differentiating a contact wound from a distant wound. A contact wound is apparent when soot is present on the outside of the skin, if there is a muzzle imprint, or if there is tearing of the skin caused by the effects of gas. However, determination of whether a wound is contact or distant can be a problem when (1) the body is decomposed; (2) the deceased has survived days or weeks after the initial wound; (3) the wound is a contact wound and there are multiple layers of clothing that filter out the soot and powder; and (4) the edges of the wound have dried in contact wounds with small caliber weapons.

Differentiation of Bullet Type Based on the Analysis of Gunshot Residue Using Inductively Coupled Plasma Mass Spectrometry*

“…Thus, the suite of elements considered potentially useful for differentiating shot from control tissue and between the two bullet types consisted of 24 Mg, 31 P, 39 K, 56 Fe, 63 Cu, 66 Zn, 121 Sb, 138 Ba, and 208 Pb. These metals could originate from the ammunition primer, gunpowder, cartridge case, or the bullet itself, as well as from the gun barrel (7). The three elements currently considered characteristic of GSR, Sb, Ba, and Pb, come from the primer, and Pb and Sb could also come from the bullet.…”

“…described four elemental combinations that were observed in GSR particles and were therefore regarded as characteristic of GSR (6). The most prominent of these combinations was antimony (Sb), barium (Ba), and lead (Pb), which come from ammunition primers and bullets (7). However, SEM/EDS is limited by the ability to locate GSR particles on the adhesive tab, which becomes difficult if the particles are embedded in the adhesive or are obscured by other debris from the sample (8,9).…”

Gunshot residue patterns on skin in angled contact and near contact gunshot wounds

“…Powder soot may help to differentiate between entrance and exit wounds, draw conclusions on the muzzle-to-target distance and on the muzzle-target angle [2][3][4]. The pattern of gunshot residues is influenced by various factors including the distance between muzzle and target, target, weapon and ammunition parameters and the muzzle-target angle [3][4][5].…”