NCJ Number
196832
Journal
Journal of Forensic Identification Volume: 52 Issue: 5 Dated: September/October 2002 Pages: 561-571
Date Published
September 2002
Length
11 pages
Annotation
This article reports on research designed to determine whether the use of dental stone, which has been commonly used to obtain three-dimensional footwear impressions at a crime scene, can be effective in lifting and preserving two-dimensional fingerprint and footwear impressions from various substrates.
Abstract
At a burglary scene at a business premises, one of the authors developed a footwear impression on a textured Arborite counter. Black magnetic powder was used to enhance this impression. After the usual photography, the author decided to use dental stone in an attempt to lift the impression. The dental stone was poured onto the enhanced impression and allowed to cure. With a slight nudge, the hardened dental stone readily released from the counter, producing an indelible, two-dimensional, exceptional-quality footwear impression embedded into the dental stone. Subsequently, both authors conducted experiments at the Toronto Police Service Forensic Identification Services lab to determine the ability of dental stone to lift two-dimensional footwear and fingerprint impressions from various surfaces. The surfaces for the footwear impressions were a dimpled plastic sterilite container lid, a dimpled plastic Rubbermaid container lid, unfinished oak, unfinished pine, a dimpled binder cover, and a smooth arborite counter top. For the fingerprint tests, impressions were deposited onto each of 13 substrates. Sixty-five fingerprints were then enhanced by using black magnetic fingerprint powder. The findings indicate that dental stone casting is a viable alternative to other more established techniques currently being used to lift and preserve footwear and fingerprint impressions. It is an excellent tool for use on surfaces previously considered unsuitable. The advantages and disadvantages of dental-stone lifts are discussed. 5 figures