Identifying pre-existing ballistic trauma in burnt bone

Abstract

Distinguishing peri-mortem trauma from heat-induced trauma is often a challenging aspect of forensic anthropology casework where fire has been used as a means of concealing evidence. This paper aims to explore the extent to which peri-mortem ballistic trauma characteristics are still present after burning and whether they can be distinguished from heat-induced fractures. This research used Sus domesticus femora and ribs that had been manually defleshed and shot with 7.92 × 57 mm Mauser ammunition at a shooting distance of 3 m, 10 m and 20 m. This type of firearm and ammunition were commonly used in a number of conflicts, such as the Spanish Civil War (1936–1939). The fracture patterns as a result of the ballistic trauma were analysed prior to placing the samples in an electric furnace, where they were heated at a peak temperature of 850 °C for 30 min. Post-burning, each fragment was analysed for ballistic and heat-induced trauma. Following reconstruction, entry and exit wound morphology and radiating fractures remained, with entry wounds being more clearly defined than exit wounds. Ballistic trauma characteristics such as bevelling were still apparent after burning. The results of this study reveal that pre-existing ballistic trauma is still identifiable after bones have been exposed to heat and it is possible to reconstruct the bones to gain a better interpretation.