Estimação estatística da posição do atirador e de ejeção de cartuchos em armas de fogo semiautomáticas.

Abstract

Understanding the dynamics of a crime scene involving a firearm is intrinsically correlated with the shooter's position at the time of the shot. However, estimating their position based solely on the location of ejected cartridges from semi-automatic firearms becomes challenging due to the inherent variability of the data, along with potential movement of the shooter. The aim of this study is to investigate the variability of ejected casings after firearm shots and thereby establish a probable shooter position region based on probabilistic models. To this end, five firearms (CZ 75 P 07, Imbel MD2 / MD6, Taurus 838/840) were used, with approximately 500 shots fired. It was possible to verify that the proposed probability distribution had a suitable fit, with casings being ejected to the right and back of the shooter in typical grips, each with distinct distances and angles in the different firearms analyzed, thus enabling the establishment of a probable shooter position area.

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