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‘Scent lineups’ spark dogfight over science

The Innocence Project of Texas said Friday that scent identification lineups, in which trained dogs determine if a suspect's smell matches the smell of crime scene evidence, are based on faulty science and have led to a number of wrongful convictions.
Keith Piekett
Fort Bend County Deputy Sheriff Keith Pikett gives his bloodhound Clue a scent to seek in May during a scent lineup on a church parking lot in Rosenburg, Texas.Bill Clough / Victoria Advocate via AP
/ Source: The Associated Press

The Innocence Project of Texas said Friday that scent identification lineups, in which trained dogs determine if a suspect's smell matches the smell of crime scene evidence, are based on faulty science and have led to a number of wrongful convictions.

The group, which tries to free the wrongly convicted, said it will release a report next week detailing at least five cases in which innocent people were arrested following scent ID lineups conducted by a Fort Bend sheriff's deputy who trains dogs. Two of the five were jailed for capital murder before the charges against them were dropped.

Deputy Keith Pikett has spent about 20 years training dogs named Clue, James Bond and Columbo to sniff out possible criminals in more than 2,000 scent identification lineups. But the lineups have come under attack from some in the legal community, and Pikett is being sued by two people who claim they were wrongly implicated in crimes because of Pikett's scent lineups.

Trained dogs are routinely at border checkpoints and airports to smell for drugs, bombs or other contraband. They're used by search and rescue teams and in other police work, such as to chase suspects.

But what Pikett does amounts to "dog whispering," the innocence group said.

"This is exactly the kind of down-home voodoo that jurors like because, hey, everybody likes a dog," said Jeff Blackburn, chief counsel for the Innocence Project of Texas. "Why don't they just have a guy who says he has a unicorn that can figure out who criminals are?"

Texas and Florida are the only states that regularly use scent identifications, Blackburn said. The Innocence Project of Florida is reviewing about 20 cases involving a now-dead dog handler who worked on three cases that later resulted in exonerations. Florida has since begun to restrict the use of scent lineups.

How a scent lineup works
During a scent lineup, an officer wipes individual pieces of gauze or cloth on a suspect and several other people, and then places them in separate coffee cans, according to the lawsuits against Pikett. A trained dog is presented a piece of crime scene evidence, and is then led by Pikett to each can for a whiff. The dog is supposed to signal Pikett if it sniffs a match.

Proponents of scent lineups argue that each person has a unique smell, and that dogs are capable of distinguishing among the subtlest of differences.

But critics say the method lacks the scientific validity of other court-approved identification methods, including DNA and fingerprint testing.

"This should not be in court," said Rex Easley, the attorney who filed both lawsuits. "It is junk, absolute junk. It's unreliable. There is no methodology and no science."

Pikett's attorney, Randall Morse, said his client denies any wrongdoing. He described him as a well-respected law enforcement official who has consulted for the FBI, the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Texas Attorney General's Office and several Texas police and sheriff's departments.

Expert witness in 40 cases
Pikett has testified as an expert witness in more than 40 cases, Morse said. In at least three cases, defense attorneys lost appeals arguing that Pikett's testimony should be inadmissible.

Pikett spent about nine years as a dog expert-for-hire while working as a high school science teacher before joining the sheriff's department full-time about 11 years ago, Morse said.

"There is a whole criminal defense bar who would tell you he is not reliable. One reason is that he does a good job of putting people away," said Morse, an assistant Fort Bend County attorney.

Doug Lowry, the president of the National Police Bloodhound Association, a nonprofit group that holds seminars on using bloodhounds in police work, said in an affidavit that he watched video of Pikett's lineups and found them "disturbing." Pikett's dogs appeared to be "just taking a walk in the park instead of conducting scent lineups."

The association stopped training police to do scent lineups several years ago because "very few bloodhound teams were found to be consistently proficient" and there were "too many variables involved," Lowry said.

In the lawsuits, the plaintiffs accuse Pikett of manufacturing evidence and say his scent lineups are merely an "elaborate performance." Pikett denies the allegations.

The lawsuits aren't the first time someone took action against Pikett. In 2008, a now former Harris County assistant prosecutor e-mailed his colleagues to warn them about the "unreliable evidence" that came from Pikett's work with Houston police, according to an affidavit.

Dr. Alejandro del Carmen, the chairman of the University of Texas at Arlington's criminology and criminal justice department, compared scent identification to primitive criminology theories that identified suspects by body type. The once-accepted theory was that skinny people were too shy and heavy people too lazy to commit crimes.

"As a trained criminologist and a Ph.D., I find it nerve-racking that the justice system would rely on the ability of a dog to predict someone's guilt or innocence," del Carmen said.

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