Major Physical Evidence in Sexual Assault Investigations (From Practical Aspects of Rape Investigation, P 96-136, 1987, Robert R Hazelwood and Ann Wolbert Burgess, eds. NCJ-105948)

• NCJ Number: 105953
• Author(s): D M Moreau
• Date Published: 1987
• Length: 41 pages
• Sale Source: Elsevier Science
• Language: English
• Country: United States of America

Annotation

This paper describes methods for collecting 'questioned' and 'known' evidence (hairs, fibers, blood, semen, and saliva) in sexual assault investigations.

Abstract

'Questioned' evidence is physical evidence typically of unknown origin when it is found. It is collected to compare with a potential source at a later time. 'Known' evidence consists of materials that must be collected as comparison standards against the questioned evidence; e.g., questioned hairs found during a crime scene search have limited value until they are compared with known hair samples taken from the suspect and the victim. Major techniques for locating and collecting 'questioned' hairs and fibers are a visual search with the naked eye, the use of oblique light and ultraviolet light, vacuuming, adhesive lifts, combing/brushing, fingernail scrapings and clippings, and use of the laser. 'Questioned' dried blood may be collected by removing the desired sample intact, scraping, or reconstructing the stain. Semen evidence is usually obtained from areas of the victim's body likely to have been exposed to the offender's ejaculation. This is done by swabbing the regions. Saliva can be located on both porous and nonporous articles, with collection techniques varying according to article characteristics. The recommended techniques for collecting 'known' samples of hairs, fibers, blood, semen, and saliva are intended to provide the laboratory with the best chance of producing optimum results from the evidence. The paper also discusses materials for packaging physical evidence. 11 suggested readings.