NCJ Number
208915
Journal
Law Enforcement Technology Volume: 32 Issue: 2 Dated: February 2005 Pages: 32,34,36,40
Date Published
February 2005
Length
7 pages
Annotation
After explaining the value of collecting and analyzing crime-scene soil samples in linking suspects to crime scenes, this article suggests techniques for such collection and analysis.
Abstract
Soil evidence is most useful when a suspect can be immediately identified before the soil from the crime scene is lost from his/her shoes. Soil evidence from the victim's or suspect's clothing can indicate an association between the victim and the suspect; for example, if a suspect lives in a neighborhood with a specific soil profile and this profile matches one found at the crime scene or on the victim, then this suggests the suspect left this sample at the scene. The evidence becomes even more convincing if there is soil from the victim's neighborhood on the suspect's clothing or shoes. The methods of collecting soil will vary from scene to scene, and the collection of soil samples will depend on the circumstances of the crime. At indoor scenes there may be footprints in soil or in dust; samples made by footwear should be photographed to scale before being recovered. Particle samples can be collected with a vacuum that has a special metal screen with a filter paper affixed to it. The filter becomes the repository for the particles and is analyzed for particle characteristics. When there is an outdoor scene, soil samples should be taken at uniform distances up to 100 yards from the site of a body. Approximately a tablespoon of soil from less than a half-inch depth should be sufficient for most modern tests. This article also discusses packaging and labeling soil samples, the collection and packaging of clothing and shoes that may contain soil samples, procedures for soil analysis, and the importance of proper communication between crime investigators and laboratory analysts regarding the nature of the evidence and the possible value of the analysis.