A Colorado man imprisoned for 15 years says he was wrongly convicted of a triple shooting inside an Adams County bar because of faulty eyewitness identification.

James Garner, 51, is challenging his conviction with help from the Korey Wise Innocence Project. He claims that three witnesses misidentified him as the shooter in a crowded bar and that new science around the unreliability of eyewitness identification should invalidate his 2012 conviction.

None of the three witnesses could pick Garner out of a photo array shortly after the shooting. They did not identify him as the shooter until three years later, during Garner’s jury trial, when the three victims, all brothers, pointed to him at the defense table and said for the first time that he was the shooter.

“That’s an enormous red flag,” said Brandon Garrett, a professor of law at Duke University. “People’s memory does not get better over time.”

Garner is due in Adams County District Court on Monday for the beginning of a two-day hearing on his petition for post-conviction relief.

He is arguing both that his attorneys failed to represent him adequately during his jury trial and that the science around eyewitness identifications has changed enough that it critically undermines the original evidence against him.

Garner doesn’t dispute that he was at the bar at West 52nd Avenue and Pecos Street on Nov. 22, 2009. He was there celebrating a birthday with several friends. About 1:30 a.m., a dispute broke out between Garner’s group of friends and a separate group at the bar, according to court records.

Someone fired at least five shots, and three brothers in the other group were wounded, the records show.

All three survived.

After the shooting, almost everyone in the bar ran away, including Garner. He dropped a pair of glasses in the chaos, and his girlfriend dropped her phone — police later used those items to identify Garner.

The three wounded brothers and the bar’s workers stayed until police arrived, court records show.

Witnesses initially gave varying descriptions of the shooter. One said the shooter was a white bald man; another said the shooter was a Hispanic man with short black hair. Another witness described the shooter as thin with a mustache.

Police never found the gun used in the shooting and did not make any arrests for several months, until they eventually identified Garner as having been present in the bar. Officers showed the witnesses a lineup of photos of five random people and Garner, to see if they could identify Garner as the shooter.

None was able to. One witness said Garner was “possibly there” and then identified one of the random people as the shooter. Another witness also picked out a random person as the shooter.

Not until Garner’s jury trial did the three brothers say they were certain the man at the defense table was the shooter that night. Garner was convicted of assault and related charges and sentenced to 32 years in prison. He will be eligible for parole in 2029.

But since his conviction, new science has shown that witnesses should not be shown a suspect’s face more than once, said Jeanne Segil, an attorney for Garner with the Korey Wise Innocence Project, an organization within the University of Colorado that provides free legal services to people who claim to be convicted wrongfully.