NCJ Number
207834
Journal
Law Enforcement Technology Volume: 31 Issue: 10 Dated: October 2004 Pages: 124,126,128-130,132,133
Date Published
October 2004
Length
7 pages
Annotation
This article discusses physical evidence collection, identification, and comparison.
Abstract
Physical evidence identification, collection, and comparison require skilled personnel who understand that the context of the crime, along with the type, amount, and quality of the evidence will determine how it is collected and analyzed. Forensic and criminal investigations are described as historical processes that uncover events that happened in the past; in these cases, crimes. The transfer and persistence of physical evidence is examined, as is the contamination of physical evidence. Any transfers of evidence occurring after the criminal activity has stopped is considered contamination, which in itself can be a type of evidence. The identification, classification, and individualization of physical evidence are next explored; the author explains that the individualization of an object involves its classification into a group with only one member. If a forensic scientist can identify properties of the evidence that are unique, the evidence can be individualized. The relationship between perpetrator and victim, as well as the context in which the crime occurred intimately affect the type of evidence collected and examined. Evidence should be collected based on the context of the crime and the relationships of those involved to avoid unnecessary work and cost. Finally, the physical evidence is compared with objects that have a known source, referred to as comparison. Differences and similarities between the evidence and other objects with known sources may make or break a criminal case.