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=Physical Evidence: Soil Analysis=

Soil

 * Soil is the natural accumulation of earth materials such as weathering rocks, minerals, decomposing plants.
 * May contain human made materials such as brick, concrete, glass, and paint.
 * How it develops depends on many factors.
 * In forensic science it is considered class characteristic evidence, but can help to focus investigators and discredit alibis.
 * The most common soils are: sand, organic matter, silt, and clay.
 * Good soils contain humus; humus in soils provides nutrients for plants and also tends to make soils darker, help soils darker, helps it remain friable, or crumbly, and moist.

A man was arrested and charged with the beating of a young girl. The scence of the crime was a construction site adjacent to a newly poured concrete wall. The soil was sand, which has been transported to the scene for construction purposes. As such, it had received additional mixing during the moving and construction process and was quite distinctive. The glove of the suspect contained sand that was similar to that found at the scene and significantly different in composition and particle size from that in the area of the suspect's home. This was important because the suspect claimed that the soil on the gloves came from his garden. What are the necessary steps a crime scene investigator and forensic scientist should take to test this soil sample?

Investigator's Job: 1.Find evidence within the evidence 2. Bag and tag the evidence 3. Bring to forensic scientist

Forensic Scientist's Job: 1.Collecting and analyzing physical evidence 2. Perform a soil analysis density lab 3.Specifically analyze fingerprints, blood, semen, firearms, saliva, and drugs 4.Compare evidence such as the soils found at both crime scenes 5.When collecting soil samples from a crime scene reference samples be taken from various intervals within a one hundred yard radius of the crime site. 6.To preserve the samples each must be wrapped with care and labeled as to the origin of the sample and whether it isa reference or crime sample.

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[|Want to know more about soil? Click this link.] [|Crime Scene Investigation]