This paper reports a study into the recovery of fingerprints in blood from fire scenes. The work aims to establish the range of temperatures and exposure times for which fingerprints in blood can survive exposure and the best practice for soot removal and subsequent fingerprint development. Tests carried out in a laboratory demonstrated that some of the protein dyes currently recommended for development of fingerprints in blood continue to develop marks after prolonged exposure of the print to 200°C. Above this temperature, marks can still be developed, but it is not possible to determine whether the original mark was in blood. Articles were also subjected to simulated fire environments, and it was further demonstrated that a range of soot removal processes could be successfully applied and marks subsequently developed. The best performing soot removal techniques included silicone rubber casting compound and Absorene. For development of marks on nonporous surfaces, acid violet 17 was most effective, whereas the best technique for porous surfaces was acid black 1. Vacuum metal deposition was capable of detecting the position of marks on surfaces exposed to 900°C.
|Number of pages||26|
|Journal||Journal of Forensic Identification|
|Publication status||Published - Jan 2008|