PHILADELPHIA (AP) — Three long-retired Philadelphia detectives went on trial Tuesday in a perjury case that examines whether police should be held responsible for alleged misconduct in exoneration cases.

It’s a highly unusual case, given that the 75- to 80-year-old former detectives face prison time if convicted. They had agreed to come out of retirement to testify at a 2016 retrial over an elderly woman’s murder in 1991. That restarted the five-year clock to file perjury charges.

“They didn’t have to come back. They came back for Louise Talley,” defense lawyer Brian McMonagle told the jury Tuesday, referring to the 77-year-old victim.

Philadelphia District Attorney Larry Krasner — who frequently sued police during his career as a civil rights lawyer — charged former detectives Martin Devlin, Manuel Santiago and Frank Jastrzembski in 2021, just before the statute of limitations was set to expire.

Talley, a widow, was raped and fatally stabbed in a neighborhood beset by the crack cocaine epidemic of the early 1990s. A 20-year-old neighbor, Anthony Wright, spent 25 years in prison before DNA testing showed he wasn’t a match for the evidence recovered. His conviction was thrown out, but Krasner’s predecessor decided to retry him.

“That case was remarkable,” Maurice Possley, a senior researcher at The National Registry of Exonerations, said of the 2016 retrial. “There was a DNA exclusion, and they said they were going to try it anyway.”

The key piece of evidence remaining was Wright’s confession. His lawyers argued that it was coerced. Police denied it.

But asked to write down the nine-page confession in real time at the retrial — as Devlin said he had done at the time — the once-famed homicide detective gave up after just a few words. The jury quickly acquitted Wright.

In court Tuesday, prosecutors said detectives had handcuffed Wright to a chair at police headquarters and threatened to “rip out” his eyes.

“So Mr. Wright signed everywhere they told him to,” Assistant District Attorney Brian Collins said.

But McMonagle read aloud statements from Wright’s associates that put him at the scene during a long night of drug use.

“Cocaine was transforming men into monsters, including Anthony Wright,” McMonagle said, doubling down on the initial police theory of the homicide case. Wright — who won a nearly $10 million settlement from the city — is expected to take the stand this week.

Krasner took office in 2018 with a focus on police accountability. He has since championed some 50 exonerations. He arrested the detectives just under the wire in August 2021.

The defense has accused his office of unfairly maligning the detectives before the grand jury. However, the Pennsylvania Supreme Court has so far declined their petition to intervene.

Santiago, 75, and Devlin, 80, are accused of lying about the confession. Jastrzembski, 77, is accused of lying about finding the victim’s clothes in Wright’s bedroom. Santiago and Jastrzembski are accused of lying when they denied knowing about the DNA problem.

All three men have pleaded not guilty. They face up to seven years in prison if convicted of perjury, a felony. They are also charged with false swearing, a misdemeanor.

McMonagle on Tuesday walked the jury back to the early 1990s, as people fled neighborhoods like Talley’s. She stayed, he said, because of her devotion to nearby church and family. The killer left with her 13-inch (33-centimeter) television and clock radio, walking past photos of President John F. Kennedy and Coretta and Martin Luther King Jr.

At least a half dozen people cooperated with police to steer them to Wright, he said, because of their fondness for Talley.

“The neighborhood was solving this case,” McMonagle said.

The trial is expected to last through much of the week.