Development of a simplified computational model to study cranial backspatter using SPH

Investigation of crime requires rigorous testing and sound scientific understanding of the evidence to assist with the reconstruction of the criminal event. From the multitude of forensic specializations, bloodstain pattern analysis evidence from cranial gunshot wounding is of particular interest because of the high mortality rate resulting from head wounding compared to other body parts. Traditionally, animal models and physical models of the human anatomy have been used to study the mechanism and extent of ballistic spatter, including backspatter. Backspatter is a retrograde spattering of the target material from the entry wound. The reverse directionality of backspatter has specific evidential value, as it may establish a link between the victim and the shooter via transfer of biological matter. Backspatter evidence has also been used in courts to distinguish between a homicide and a suicide. Despite the importance of backspatter, the understanding of its mechanism has remained inadequate due to ethical issues, difference in anatomical geometry associated with various animal samples, or material property difference among biological and synthetic materials used in physical models. Hence there is a need to develop simulation tools that will use computational models of cranium geometry and configurations relatively similar to those of humans. Such computational models can act as alternatives to animal or physical models for the investigation of backspatter in a variety of situations.