NCJ Number
212359
Journal
Journal of Forensic Identification Volume: 55 Issue: 6 Dated: November/December 2005 Pages: 711-725
Date Published
November 2005
Length
15 pages
Annotation
This article reports on experiments carried out at the Canadian Police College (CPC) on the use of BackTrack, a computer program that analyzes bloodstain patterns.
Abstract
Bloodstain pattern analysis allows forensic investigators to reconstruct events of a crime scene and to determine the approximate position of the victim as well as the direction of inflicted blows. The determination of bloodstain impact angles relies on trigonometric relationships, the calculations of which have been incorporated into a computer program called BackTrack. The program allows investigators to calculate the virtual flight paths of blood droplets in three-dimensional representations using digital photographs as data. The experiments carried out at the CPC involved the use of two mock crime scene bloodstain patterns, which were analyzed by BackTrack and rendered in three-dimensional representations for court presentation. In both cases, BackTrack was able to successfully determine the location of the blood source within 6 cm. The experiment also successfully incorporated virtual bloodstain projection strings into AutoCAD to show the virtual flight paths of blood droplets. Figures, table, references