If someone said that dogs have provided ‘irrefutable’ evidence in criminal courts, this would most likely be met with skepticism, laughter or disdain. However, this is what has happened in several jurisdictions, largely enabled by admissibility frameworks that treat such evidence as capable of belief. The dog does not appear in court to woof its testimony. Instead its evidence is heard through a proxy or an intermediary, namely the dog handler. That dogs have an olfactory system that far exceeds that of humans is accepted and not refuted. However, that ‘dog testimony’ has been the known source of wrongful convictions also needs to be acknowledged. For example, William Dillon was convicted of murder in Florida, USA, in 1981 and spent nearly 27 years in prison based on testimony from a dog handler, questionable eyewitness identification and a jailhouse informant. The dog handler testified that his dog had linked Dillon to the crime scene and a T-shirt worn by the perpetrator (The National Registry of Exonerations, 2012a). DNA testing of the T-shirt, which had the victim’s blood on it, excluded Dillon and he was exonerated in 2008 (Innocence Project, no date). This is only one example of a dog handler exaggerating or misunderstanding the capability of their dog in a criminal investigation and subsequent court case. Many more cases exist from a variety of fields including fire and arson investigations.
