Dishing the Dirt

NZ scientists at the Institute of Environmental Science and Research have developed a high-tech yet cost-effective new crime -fighting technique. The revolutionary system uses DNA analysis of the bacteria in soil to match a database of samples – the equivalent of a soil “fingerprint.” Says study leader Jacqui Horswell, “If the person says I didn’t murder her because I didn’t go into that back garden, you can say, actually, I think you’ll find you did.” Unlike current techniques, which involve hiring pricey experts, the ESR kit can be used by any forensic scientist familiar with molecular biology. In a spin-off study, doctoral student Rachel Parkinson is creating a tool which will be able to pinpoint a victim’s time of death by looking at the bacteria the body produces as it decomposes and its presence in the surrounding soil. Both studies have sparked considerable international interest, particularly from the University of Tennessee Forensic Anthropology Facility, known as the “Body Farm.”