Authors: Rust, L.1, Nizio, K.D.2, Forbes, S.L.2

1Forensics, Australian Federal Police, GPO Box 401, Canberra, ACT, 2601 Australia; 2Centre for Forensic Science, University of Technology Sydney, PO Box 123, Broadway, NSW, 2007 Australia; 3Département de Chimie, Biochimie et Physique, Université du Québec à Trois-Rivières, 3351, boul. des Forges, Trois-Rivières (Qc.), G9A 5H7, Canada

Bloodhounds are an iconic figure in the scent detection dog history, however the use of blood-detection dogs which are specifically trained to track blood as evidence for criminal investigations, are a relatively new tool in contemporary policing. Having only been introduced by law enforcement agencies around the world in the last two decades, these specialised canines can assist to streamline crime scene searches as an effective presumptive test for latent and minute traces of blood, succeeding where other techniques may be ineffective or costly for an investigation.
Blood-detection dogs have been utilised in several countries and operationally proven as a valuable resource for tracking individuals involved in violent crimes, sexual assaults, and homicides. Discussion on research and case studies involving blood-detection dogs and cadaver-detection dogs, including the analysis of blood training aids, will highlight the strengths and limitations of these canines in policing investigations. Topics covered include fresh vs degraded blood, animal vs human blood, latent blood limitations, and blood donor implications on the efficacy of blood-detection canines.
Results of the various studies presented indicate that the olfactory system of blood-detection dogs are much more sensitive than current scientific techniques, and that their scenting abilities can provide investigators with valuable information that may potentially be overlooked during preliminary searches with traditional policing tools. Despite the infancy of these specialised canines and the small sample sizes represented world-wide and in research, the data presented promotes strong support for the validity of blood-detection dogs in crime scene searches and as powerful biosensors for law enforcement.