Monday, July 13, 2009

Scent lineups by dogs don't pass the smell test

In the wake of a report this spring by the National Academy of Sciences, more scrutiny than ever has been focused on untested and unproven forensic techniques. In that vein, yesterday, the Victoria Advocate ran a terrific story by reporter Leslie Wilber ("Does it pass the smell test," July 12) about the use of "scent lineups," a highly dubious forensic technique which, in Texas, is performed by just one man - Fort Bend Sheriff's Deputy Keith Pikett and his three bloodhounds. Wilber examines the technique closely and finds that it doesn't even enjoy national acceptance among police dog handlers:

The National Police Bloodhound Association quit endorsing the technique years ago, calling scent lineups unreliable.

"We don't even want to take a chance on that," said Doug Lowry, the group's president and a chief instructor.

Kevin Kocher, president of the National Bloodhound Training Institute, said he doesn't run lineups and finds them hard to defend.

Critics list several potential weaknesses of scent identification:

Handler or observer influence. Dogs are eager to please and can pick up subtle cues, especially if lineups are conducted on leash, said Steven Nicely, a police-dog handler-turned-defense witness. Handlers can read observers and unintentionally relay that information to the dogs.

"They learn about the pressure on the leash and the way you stand," Nicely said.

Sample contamination. Lineups typically include a suspect's scent and scents from five other people. The samples should all be fresh and about the same age because scent fades over time.

The pads should be handled carefully, to avoid contamination, and lineups should be conducted in clean rooms, without distracting smells. Human scent is best stored in glass jars at room temperature and out of direct light, Fulton said.

Handler reliability. Dogs can't talk, so handlers are their voice in the courtroom. Affidavits should be precise. Records should be detailed, showing errors and successes.

"As a dog handler, you'd better be acting as a scientist," Nicely said. "Otherwise, you're acting on myth and folklore."

And in what forensic lab does Pikett perform his procedures? He still "performs scent lineups daily in the parking lot of Pilgrim Journey Baptist Church in Rosenberg." Definitely no risk of evidence contamination in a church parking lot, huh?

One academic claimed that "The best-run scent lineups can provide results as accurate as witness identification lineups," but given how unreliable eyewitness identification can be, perhaps that's damning with faint praise.

Civil litigation in Victoria may soon subject scent lineups to much greater scrutiny than Texas criminal courts have ever afforded the technique. For example:

In one motion, [attorney Rex] Easley wrote Pikett's lineup was "so recklessly flawed that it violated the constitutional rights of the plaintiff. First, the dogs were leashed during the lineup, which fails to exclude handler input. Second, the site, the pads and the cans were contaminated with countless other scents so as to render it unreliable and impermissible to base a warrant upon."

Easley hired Bob Coote, who led a police-dog force in the United Kingdom and worked with scent dogs guarding the British border, to review Pikett's work in Buchanek's case. The lineup was "the most primitive evidential police procedure I have ever witnessed. If it was not for the fact that this is a serious matter, I could have been watching a comedy," Coote wrote.

Jeff Blackburn, chief counsel for the Innocence Project of Texas (and for a couple of more weeks, my boss), summed up my own view of Pikett's scent evidence with this pithy one-liner: "This is junk science. This isn't even science. This is just junk."

Pikett claims to have used his dogs in more than 2,000 criminal cases, which makes me wonder how many more false convictions are out there based on this type of unreliable pseudo-evidence?

MORE: See another excellent Victoria Advocate article giving lots more background on Pikett's career and techniques as a dog handler, which began as a hobby undertaken with his wife while he was a high-school teacher. Leslie Wilber is providing top-flight coverage on this story for a small-town paper.

See prior Grits coverage:


Red Leatherman said...

I suppose that as long as the defense gets to choose the translator for the dog.......

At best it's an art not science

My wife interprets all the cute things our little doggie says.

I deleted the personal experience rant I just typed, your welcome.

Andres Morin III said...

What's next?? voodoo? crystal balls?