Special Reports

BY TRANSFORMING the analysis of stab wounds from crude guesswork into a quantitative science, forensic engineers in Wales hope to produce a new tool for solving murder cases. Working with Home Office pathologists, they are developing a database that should tell the courts exactly how much force was used to inflict a victim's wounds.

The analysis of stab wounds has lagged behind the powerful techniques developed for analysing events such as fires, car crashes and bombings. Forensic scientists are often asked to comment on the force that would have been required to inflict a wound—which can be important in determining whether someone accused of murder intended to kill, or whether they had the strength to inflict the fatal injury. But at present, expert witnesses can usually give only a subjective assessment.

Leonard Nokes, Mike Jones and their colleagues at the University of Wales, Cardiff, are collecting data by attempting to reproduce stab wounds on the actual murder victims. "We get the permission of the authorities and the relatives of the deceased before we carry out any testing," Nokes stresses. Already, data from some of the team's tests have been presented as evidence in court.

The goal, however, is to remove the need to conduct such gruesome experiments. By compiling a database of the characteristics of wounds created with different implements and degrees of force, the Cardiff team aims to create a computer system that can accurately determine the force needed to inflict a victim's wounds.

"Eventually, this research will allow us to build up a computer model so we can analyse wounds without resorting to bodies," Nokes says. The researchers are also developing clay-like materials that mimic the mechanical properties of human flesh. Nokes told the BA that they expect to complete their database in two years' time. Their research may also help companies working to improve the design of stab-proof body armour.