Removing Interfering Contaminations From Gelatin Lifters

• NCJ Number: 212646
• Journal: Journal of Forensic Sciences Volume: 50 Issue: 6 Dated: November 2005 Pages: 1386-1393
• Author(s): Yaron Shor M.Sc.; Tsadok Tsach M.Sc.; Sarena Wiesner M.Sc.; Gur Meir
• Date Published: November 2005
• Length: 8 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

This article describes the testing of a technique for removing contaminants from gelatin lifters, which are widely used for recovering shoeprints from crime scenes.

Abstract

Gelatin lifters collect less dust than adhesive lifters and are therefore more suitable for lifting shoeprints from loosely fibrous materials such as paper, clothes (flannel), and corrugated cardboard; however, the disadvantage of pressing a gelatin lifter on such substrata is that it lifts a large quantity of loose fibers, which causes the dusty footwear imprints to be covered with displaced fibers, often rendering the shoeprints invisible to the examiner. The current study placed several shoeprints on fibrous substrates such as corrugated cardboard, flannel cloth, and handmade fibrous paper. The press method was then applied. In most cases, this resulted in concealing dusty shoeprints with detached fibers of the substrates. Researchers then applied a 333 x 175mm adhesive lifter ("white JAC vinyl" manufactured by Industrial Self Adhesives Ltd of Nottingham, England) directly onto the adhesive side of the gelatin lifter. This application used a roller to prevent air pockets. The adhesive lifter was removed immediately, revealing that many of the fibers that concealed the shoeprint had been transferred to the adhesive lifter. The procedure was repeated several times. The small dust particles that formed the shoeprint remained attached to the sticky side of the gelatin lifter, even after force was applied to the roller that pressed the adhesive lifter on the gelatin lifter. The advantages of this means of increasing the clarity of shoeprints are greater than the risks of possibly relocating the dust that forms the shoeprints on the gelatin lifter or reducing image quality. Repeating the procedure too many times increases the risk that the print quality will be impaired. 7 figures and 6 references