(CN) - A murder conviction based largely on scent evidence from a police dog with a history of misidentification cannot stand, the 9th Circuit ruled Monday.
Gilbert Aguilar was convicted for the first-degree murder of John Guerrero in 2001. The shooting occurred when Guerrero drove into a neighborhood of La Puente, Calif., and drew the attention of alleged gang members. Guerrero pulled into a KFC parking, where a young Hispanic male in baseball cap got out of a white Volkswagen Beetle and shot him seven times. Witnesses said the shooter then returned to the Beetle and it drove away.
About a month after the shooting, a probation officer saw a sketch based on eyewitness descriptions and thought he recognized Aguilar. Later, three eyewitnesses picked him out of a photograph lineup, but some of them would change their story at trial.
Critical to the prosecution's case was evidence that Reilly, a Los Angeles Police dog, had identified Aguilar's scent on a white Volkswagen Beetle officers impounded as stolen a few weeks after the murder.
While Aguilar's fingerprints did not match those found in car, Reilly's alert allegedly confirmed the presence of Aguilar's scent in the front passenger seat.
For his part, Aguilar argued that the real murderer was Richard Osuna, aka "Gangster," whose brother had been shot a few days before the Guerrero murder. Aguilar noted that two witnesses claimed to have seen Osuna going after Guerrero in a white Beetle.
Nonetheless, the prosecutor "expressly told the police not to pursue an investigation of Osuna," according to the ruling. At the time of the shooting, Aguilar was 20 years old and about 6 feet tall, while Osuna was 16 and no taller than 5'7.
A jury convicted Aguilar of murder and sentenced him to prison for 50 years to life.
Later, while appealing the case in California, Aguilar's attorney discovered that Reilly had a history of misidentification.
In addition to evidence that the dog made at least two prior mistakes, Aguilar showed that prosecutors knew Reilly was unreliable at least six months before Aguilar's trial.
The California Court of Appeals nevertheless affirmed the conviction and the California Supreme Court denied review. Aguilar then filed a petition for habeas corpus, which a federal judge in Los Angeles denied in 2006.
A three-judge panel of the 9th Circuit reversed on Monday and ordered the lower court to grant Aguilar a new trial or release him.
"Reilly's scent evidence was the only evidence at trial linking Aguilar to the getaway car, as well as the only evidence corroborating strikingly weak eyewitness identifications," Judge William Fletcher for the Pasadena-based panel.
The panel found that California had downplayed the importance of Reilly's alert, and had "misstated the nature of the eyewitness testimony, making it appear stronger than it was."
"The jury was told to use the dog scent identification 'for the purpose of showing ... that the defendant is a perpetrator of the crime of murder,'" Fletcher wrote. "The State cannot now argue with a straight face that the evidence upon which it relied so heavily at trial was, in fact, not probative."
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