In 2012, I was approached by an attorney who sponsored the Crime Stoppers television programs I produced. He had an idea for a documentary about a wrongful conviction. Very cool. I loved The Thin Blue Line. There were only two wrinkles, he explained. First, the wrongfully convicted guy actually replaced another guy who the state says was wrongfully convicted. Second, the new guy confessed and plead guilty. And so began an odyssey that leads up to the movie I co-directed, A Murder in the Park, which is now playing in theaters.

America was rocked when, in 1999, the state of Illinois nearly executed Anthony Porter. Fifteen years after being sentenced for a double murder, and just 48 hours away from lethal injection, he filled out the menu for his last meal, and was measured for his state-issued coffin. In a last-ditch effort to delay the execution, attorneys argued that his IQ was 51, and a judge ordered a stay. This gave a team of Northwestern University journalism undergrads and their crusading professor David Protess, who taught investigative reporting at Northwestern’s Medill School of Journalism and founded the Medill Innocence Project, enough time to re-investigate the case. What the Northwestern team quickly achieved was nothing short of a miracle. They found new witnesses, secured an affidavit from an original witness changing his story, and confronted the “real killer,” Alstory Simon, even securing his videotaped confession. Chicago watched it unfold on the local news. Every few days there was a new development as Team Northwestern exposed the ineptitude—or worse—of the Chicago Police Department and local prosecutors. The cops couldn’t get it right, but the “kids” could.

The people of Illinois, including the Governor, wondered how many more innocent men were sitting on death row, victims of shoddy or discriminatory police work. The Governor vacated the capital sentences of all death row inmates, the beginning of the end for Illinois’ death penalty. Later, Senator Patrick Leahy would quiz future Chief Justice John Roberts about the case during Roberts’ senate confirmation. The near-execution of Anthony Porter was definitive proof of just how flawed the system was.

We now know that a little bit of digging would have shown any objective observer that the police conducted a clinical, textbook investigation. But that wouldn’t make for sexy headlines. And anyway, it was far easier for television and print media to re-report the narrative the university provided.

Before the state charged Simon with the murders, a grand jury was summoned to find out what really happened to the victims—teenage sweethearts Jerry Hillard and Marilyn Green. They called some of the original witnesses from the 1982 murder, all of whom placed Porter near the victims, or saw him pull the trigger. They also questioned the students, professor, and private investigator from Northwestern who re-solved the case. What the grand jury learned was stunning. The Northwestern team not only didn’t interview four of the five living witnesses, but they testified under oath they didn’t even know about them. One grand juror asked a student if she had been used as a pawn. Prosecutors didn’t bother asking these grand jurors to return an indictment. Instead, they formed another grand jury and didn’t call any of the witnesses implicating Porter. That second grand jury indicted Simon.

No one in the original police report mentioned Alstory Simon. The new witnesses implicating Simon were his ex-wife and her imprisoned nephew. Six years later, the two would admit they made up the Simon story for reasons including owing Porter a jailhouse favor, and promises of money and legal assistance.

As for his confession, Simon claimed that armed private investigators sent by Northwestern invaded his Milwaukee home in the early morning, impersonating police detectives from Chicago. They showed him the statements of his ex-wife and her nephew claiming he committed the crime. They also played a videotape of another witness claiming to have seen Simon commit the killing. The witness ended up being a fake—an actor hired by the detectives to read a script. Simon wouldn’t find that out for a long time. In his mind—whether he did it or not—his goose was cooked. Luckily for him the lead private investigator had a plan. Simon could claim self-defense, plead guilty, and not only would he avoid the death penalty, something that Simon said terrorized him, but he’d only serve about two years, and after he got out, there’d be money to be shared with him from the book and movie deals the case would generate. He had a half-hour to accept the plan. He did. They provided him with a free attorney, and he—with this attorney’s blessing—started implicating himself in a crime he didn’t commit.

Weeks later Simon had second thoughts, telling his pastor and attorney that he was going to tell the judge the truth: that he didn’t know anything about the murder. He was also going to disclose the promises that were made. Upon hearing this, his attorney, a friend and office mate of one of the police impersonators, shared an unfortunate new development: Alstory was now a suspect in a Milwaukee murder, and now would surely be facing the death penalty in either Wisconsin or Illinois... maybe both. Maybe he could work something out. The double-down worked, and Simon stuck to the plan. He plead guilty in a deal that included a 37-year sentence. He apologized to the victims’ families in court and later to a TV reporter, and headed to prison hoping the Northwestern team would honor their promise. They wouldn’t. Two years later, when Simon received the grand jury transcripts, he learned for the first time that six witnesses had placed Porter in the park, and two saw him pull the trigger. He also learned that Milwaukee prosecutors never considered him a suspect in their murder. He realized then how badly he was tricked. The evidence against him was suspect, there was a stack of evidence against Porter, and his attorney could probably have suppressed his videotaped confession due to the circumstances.

A couple of retired federal agents, Jim Delorto and John Mazzola, heard about the case and visited Simon. They compiled volumes of evidence confirming his account as well as Porter’s guilt. They connected with William Crawford, a recently retired Pulitzer-winning reporter from the Chicago Tribune, and the team spent the past ten years, along with Simon’s new attorneys, shouting from the rooftops about this case. No one listened until 2013, when the Illinois State’s Attorney of Cook County decided to take a closer look at the case with her Conviction Integrity Unit.

The film has an unexpected ending—one that will give viewers at least partial closure.

For my part, I don’t believe this case says anything about the wrongful conviction movement in general. I believe it’s a perverted, stand-alone example of good intentions gone awry, with plenty of rushing and corner-cutting that had no place in an investigation of this magnitude. It also exposes a glaring lack of oversight on the part of Northwestern University. Years later, they would learn and publicly admit disturbing facts about this program and its leadership. Still, even then, they wouldn’t lift a finger to help Alstory Simon as he languished in prison.