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Guide to Interpreting Single Locus Profiles of DNA Mixtures in Forensic Cases

NCJ Number
132314
Journal
Journal of the Forensic Society Volume: 31 Issue: 1 Dated: (January/March 1991) Pages: 41-47
Author(s)
I W Evett; C Buffery; G Willott; D Stoney
Date Published
1991
Length
7 pages
Annotation
The interpretation of single locus probe (SLP) analysis of a mixed body fluid crime samples is discussed in reference to a multiple rape case.
Abstract
SLP analysis may give rise to several bands. If a suspect's profile is found to match two of the bands, then evaluation of the evidential strength requires careful interpretation. The SLP profile from a vaginal swab was compared with that from a sample from a single suspect. In the first case example, a situation is addressed in which the crime sample revealed four bands, and in the second case example, the crime sample revealed only three bands. Analysis of these results presents principles of the interpretive process which can serve as a guide to caseworkers analyzing similar cases. Following some illustrative numerical examples of the probabilities in which two men could contribute the necessary bands to make up the crime profile, these principles are extended to more complex cases. 1 table, 2 figures, and 2 references (Author abstract modified)