Application of Amido Black Mixture for the Development of Blood-based Fingerprints on Human Skin

• NCJ Number: 201261
• Journal: Journal of Forensic Identification Volume: 53 Issue: 4 Dated: July/August 2003 Pages: 404-408
• Author(s): Rodney Lawley
• Date Published: July 2003
• Length: 5 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

This article describes a case in which amido black -- a chemical blood reagent often used by forensic specialists in the development of blood-based latent prints on porous and nonporous surfaces -- was successfully used to develop prints from the dermal surface of a homicide victim.

Abstract

Amido black is a chemical dye solution that binds to protein molecules in blood and yields a dark blue color. This color change darkens the bloody area to such a degree that many fine details, such as dermal ridge impressions, can become clearly visible. In the case described in this article, the victim's body had multiple stab wounds to the upper torso, with bloody smears on the ankles, both legs, and the wrist area of both hands. This evidence suggested the possibility of a violent physical struggle between the victim and the attacker that may have left the attacker's latent prints on the victim's body. The body was first examined with an alternate light source for serological fluids, inherently fluorescent latent prints, and other types of trace evidence. This procedure did not produce any ridge detail, but did indicate the possibility of finger marks on the inner thigh of the victim. Following a fuming procedure on the body with "super glue," investigators conducted an immediate examination of the dermal surface using the alternate light source. Also, a feather-type fingerprint brush was used to apply a fluorescent powder to the skin surface. No latent prints appeared. Amido black was then applied to the bloodstained areas of the body. The developer was lightly sprayed onto the affected area with a common spray bottle. Both the amido black and the rinse solution were sprayed above the target area and allowed to slowly gravitate across the stain. Previously undetected ridge detail was located on the inner right thigh of the body, and an additional nonridge imprint of the attacker's finger position was obtained on the same upper thigh area of the victim. The detail, however, was not sufficient for a suspect comparison, but it demonstrated the promise of this new application for future homicide investigations. 3 references