Dogs, especially their noses, have been an important law enforcement tool for ages, whether its scent tracking or sniffing out drugs or explosives. But one use has come under harsh criticism recently: the dog-scent lineup, reports The New York Times.
In a dog-scent lineup, a dog smells contaminated items from the crime scene thought to hold the suspect's scent and then sniffs at scents swabbed from the suspect and other innocent people that match the suspect's description. The point is to have the dog signal his handler when it recognizes the scent from the crime scene during the scent lineup. If the dog signals a particular scent, it means the person attached to that scent was present at the location of the crime.
This is what happened to Curvis Bickham in Texas, when a dog signaled that his scent matched the scent left at a triple homicide. Bickham was arrested for capital murder, a death-penalty offense. One problem: he was innocent, and 8 months later he was released when another man confessed to the crime.
According to the Times, dog-scent lineups cannot convict someone beyond a reasonable doubt.
Scent lineups, however, are different. Critics say that the possibilities of cross-contamination of scent are great, and that the procedures are rarely well controlled. Nonetheless, although some courts have rejected evidence from them, the technique has been used in many states, including Alaska, Florida, New York and Texas, said Lawrence J. Myers, an associate professor of animal behavior at the Auburn University College of Veterinary Medicine.
The FBI, while defending the use of scent dogs to establish connections to a crime, said in a 2004 report that dog scent evidence should only be used to corroborate other evidence, reports the Times. Other studies note that dogs cannot flawlessly identify people by scent.
The Innocence Project of Texas, a group of volunteer lawyers and law students that work to release people wrongfully convicted of crimes, has a much stronger critique of dog-scent lineups. The nonprofit legal organization calls it "junk science injustice."
And because science carries so much esteem in society and the courtroom, passing off junk science as real science can corrupt the legal system.
"In the hands of a skilled prosecutor," the report warns "scientific-sounding testimony from any source, no matter how fraudulent, can be played to great dramatic effect and win convictions."
The Innocence Project of Texas is particularly incensed that Texas has relied on one dog handler in particular, Deputy Keith A. Pikett of the Fort Bend County, Texas, Sheriff’s Department, to confirm suspects were at a crime scene. Pikett has no professional training to use scent dogs and is now the target of multiple lawsuits from victims that were wrongfully accused of crimes by his dog-scent lineups.
The Innocence Project of Texas is calling for the state to prohibit the use of dog-scent lineups during investigations.
♦ Photo of bloodhound by Sarhounds/Flickr