A case study in forensic soil examination from China

Soil examination can provide useful forensic information about the spatial location and human activities of a suspect. Soil is widely used in criminal investigations. In a case that occurred in the countryside of Jilin Province, in the NE of China, soil was found adhering to clothing on a body. Examination of plant debris in the soil using plant DNA barcoding technique found it to be ginseng root, which indicated that the soil might have come from a ginseng plantation. In the first instance, it helped in finding the place where the body was initially buried. Then a comparison was made between the soil recovered from the body and from the ginseng plantation. Composite analysis of minerals, pollen types and elements provided additional information to assist in making comparisons. Trace amounts of soil located on the body played an important role in locating the burial site and was regarded as the most valuable evidence in convicting the suspect of murder even without the suspect's DNA being available.