Soil as significant evidence in a sexual assault/attempted homicide case
In October 1999, a woman and her two small children were assaulted by a male acquaintance on the banks of the New River in the Imperial Valley desert region of California, USA, approximately 160 km east of San Diego. The area includes a number of agricultural fields, old lake deposits, sand dunes and the Salton Sea, a large saline inland sea. The victims escaped from the suspect and hid for 30 h in the New River, thus diminishing the possibility of obtaining physiological fluids as evidence for DNA testing. Wet and soiled clothing and shoes were collected from a suspect's residence within hours of the assault being reported. The suspect denied any contact with the victims or with the crime scene. Analyses of the soil on the suspect's clothing and shoes, and of crime scene soil using microscopical methods and X-ray diffraction, indicated that the soil from the crime scene and soil on the suspect's clothing and shoes were similar. Predominant wind directions and observations of the soil distribution at the crime scene added significance to the observed similarities between the soil samples at the crime scene and the soil on the suspect's clothing and shoes.
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Forensic Geoscience: Principles, Techniques and Applications
Forensic geoscience is an increasingly important sub-discipline within geoscience and forensic science. Although minerals, soils, dusts and rock fragments have been used as only begun to be recognized in the last ten years or so. The police and other investigative bodies are keen to encourage such developments in the fight against crime, particularly since many criminals show a high level of forensic awareness with regard to evidence such as fingerprints, blood and other body fluids. The papers in this volume illustrate some of the main principles, techniques and applications in current forensic geoscience, covering research and casework in the UK and internationally. The techniques described range from macro-scale field geophysical investigations to micro-scale laboratory studies of the chemical and textural properties of individual particles. In addition to forensic applications, many of these techniques have broad utility in geological, geomorphological, soil science and archaeological research.