Molecular ballistics connects the molecular genetic analysis of biological traces with the wounding events and complex forensic traces investigated in terminal ballistics.
Backspatter, which originates from a projectile hitting a biological target when blood and/or tissue is propelled back into the direction of the gun, is of particular interest. Those traces of backspatter can consolidate and persist on the outer and inner surfaces of firearms and serve as evidence in criminal investigations.
This is the first research wherein an anatomically correct skull model comprising a commercially available and standardized SYNBONE skull replica covered with rubber, an internally attached triple-contrast mix (blood – acrylic paint – contrast agent) reservoir as source of trace material, and a core of 10% ballistic gelatin as brain simulant was tested for its usability and suitability in molecular ballistic backspatter research.
The model was intended as a closer approximation to and for better comparability with real gunshot scenarios to the head than offered by previous head models.
The results were promising and regarded as proof of principle. Backspatter was produced by both pistol and shotgun shots and could successfully be analysed by forensic DNA profiling. Apart from the blank cartridge guns, all gunshots penetrated the skull model and created backspatter, which was recovered from the distal part of the barrels and analysed. The pistol contact shots and one of three shotgun shots yielded full STR profiles. The shape of the visible backspatter marks on the gun and hand of the shooter ranged from dots and smears to elongated shapes and “exclamation marks” which could be attributed to the direction of their origin, depending on the velocity and angle at the time of the impact.
This complete model setup proved to be well applicable to molecular ballistic research as well as wound channel and fracture pattern investigation.
Euteneuer, J., Gosch, A., Cachée, P., & Courts, C. (2019). Evaluation of the backspatter generation and wound profiles of an anatomically correct skull model for molecular ballistics. International journal of legal medicine, 133(6), 1839-1850.