Lisenko I. Traces and injuries on person's clothes and body from the action of domestic-made bullets with polymer components under smooth-bore firearms shots and their forensic importance

The dissertation work is devoted to forensic evaluation of injuries and traces left by domestic-made bullets with polymer components (PCs) under smooth-bore firearms shots on human body and clothes tissues. Trace formation was studied for six grades of bullets with PCs - "Brennecke-Silver", "Taho-12", "Sputnik", "Sport", "Trio" and "Diabolo". On the basis of studies in design peculiarities of cartridges equipped with the above bullets the classification of smooth-bore firearms bullets and the classification of polymer components of cartridges was supplemented. It was found that the presence and distribution of traces and injuries on tissue targets were caused by bullet design characteristics, cartridge polymer components and shooting distance, thus, they may be treated as diagnostic criteria. To reveal barely noticeable traces of polymer a microscopic study in UV rays was proposed. The difference between trace formation on human body and on clothes tissues lies in the fact that the traces from shot factor effect are less evident on skin, whereas small polymer particles are poorly fixed to it. Statistically valid linear regression models were built for determination of shooting distance. A block scheme was developed for algorithm permitting to select a particular mathematical model as working hypothesis to determine shooting distance.