Texas has had its fair share of forensic science grief these last few months. Mostly notably, a big argument has erupted over the execution of an apparently innocent man (many articles on the subject, including this one, about Cameron Todd Willingham who was wrongly convicted on the basis of forensic evidence later shown to be incorrect).
The State is now in hot water over its continued and questionable use of dogs to identify perpetrators using a dog scent line up. Basically, a swab is rubbed over an item of interest, such as a rope used to strangle a murder victim. The swab is placed in a tin. Several other tins are lined up, each with a swab from a different person (including one from the the suspect). Dog is allowed to sniff crime scene swab then sniffs the swabs taken from people. Dog “matches” crime scene scent with suspect’s scent – suspect arrested and charged with heinous crime.
The Innocence Project has now got involved because, I believe quite rightly, this is not a scientific method that can be shown to be reliable or reproducible. To my knowledge, there is not a body of well-researched, peer-reviewed scientific literature backing up this method of ID.
Let’s hope this method doesn’t take off over here – at least not until the scientific sector is convinced it has been exhaustively examined, considered, tested and that the courts accept it BEFORE someone is charged with a serious offence. In my opinion, a case should not stand on one evidence type alone – something a bit more than a dog sniff and a police report should be required.