Davontae Sanford was released Wednesday from prison after serving nine years for a murder to which he confessed, but the state now doubts he committed.

Sanford is 23, but was 14 when he said he'd killed four people inside a Detroit home. He is blind in one eye because someone had thrown an egg at him when he was nine. As a teenager, he was enrolled in special-education classes. He lived in a rough part of Detroit and tried to fit in by claiming to be part of a gang, or bragging about fights he'd never had. Sanford was an unlikely suspect. So it made more sense when another man, a Detroit contract killer named Vincent Smothers, confessed to the crime in 2008. 

After state police reinvestigated his case, a county judge on Tuesday vacated Sanford's conviction and ordered him released. It took almost nine years. 

"I just want to try and put this behind me and move on with my life and move forward with my family,"Sanford told reporters Wednesday. "Take one day at a time, one step at a time." 

His mother, Taminko Sanford-Tilmon, said: "Right now, today, I'm just sucking all of this in." Then the family went inside. 

Sanford's story is remarkable in that it wasn't DNA that freed him, as is often the case. He had help from the Michigan Innocence Clinic, the Center on Wrongful Convictions of Youth at Northwestern University, and Dykema Gossett, the law firm. What freed Sanford was a re-examination of his own confession--one he said he made up under the pressure of police interrogation.

Typically, when a suspect admits to a crime--especially something as serious as quadruple murder--conviction is inevitable, because why would someone lie about that?

"Everyone had assumed that confessions were the gold standard," Saul Kassin, a professor of psychology at the John Jay College of Criminal Justice, told me.

But when people think that, Kassin brings up a statistic he cited in a paper he wrote called "Police-Induced Confessions: Risk Factors and Recommendations." In it he points out that in 15-to 20 percent of cases where a person has been convicted of a crime, then exonerated by DNA, the suspect confessed—meaning up to 1 in 5 of those confessions were false. 

The path to Sanford's near-decade stay in prison started on September 18, 2007, at 1 a.m. A police dog  tracked a scent from the house on Runyon Street where the killings occurred to a vacant lot across the street. Officer Michael Russell was searching that area when Sanford, who lived a couple blocks away, came by. There's discrepancy about what happened next, but in a report by Jim Trainum, a former Washington, D.C., police detective who reinvestigated the case for the Center on Wrongful Convictions of Youth, Russell said Sanford approached. "He knew what I was investigating," Russell said.

The other officer there said Russell first questioned Sanford, who then said he didn't want to help. They chatted anyway. Sanford, it turned out, was related to a former Detroit homicide detective, whom one of the officers knew. They called the officer, who told Sanford to "be truthful." Suddenly, Sanford knew about the suspects. He said he'd seen people with guns run through his yard and knew them as part of a local gang. If the officers wanted, Sanford said, he could point out where they were.

For about two hours, the officers drove the teenager through the neighborhood in an unmarked police car and returned to the crime scene. There's no record of what happened in that time, but by 4 a.m. they'd come to the police station where inside an interrogation room Sanford waived his Miranda rights. The typed confession Russell prepared read that Sanford admitted he and three friends planned to rob the house on Runyon Street. They'd first met at a restaurant, then passed out guns. On the drive to the house, according to this first confession, Sanford asked to get out of the car before they reached the house on Runyon Street, then he walked home. He was there when he said his friend jumped through the backyard and shouted to Sanford that he'd shot someone. 

The officers let Sanford go. That afternoon, and in the following days, police visited the friends Sanford named. They were arrested, but never charged. Sanford's story didn't make sense: The restaurant he claimed to have met at had been closed for months; Sanford didn't match any of the descriptions given by witnesses who saw two—not four—men run from the house; and the caliber of guns Sanford described were wrong. But two subsequent confessions were closer to what the police needed.

The next day, police picked up Sanford again and interrogated him. The second session was not recorded, and the only evidence of what happened is a final statement the officer typed. This time, Sanford said he and three friends met at a park (not a restaurant) and his description of the guns matched those used in the killings. In Sanford's third interrogation, he said two friends drove away in a van (a different vehicle than in the first and second confessions) and that he and an accomplice ran away from the house—an account that would match what witnesses said they saw.

Eventually, officers would say Sanford described where the bodies lay in the house, something only the killer would know.

"The way the interrogation process is set up in this country is that it's designed not to get information from you, but to get a confessions," Trainum, the former Washington D.C., detective told me. "I'm only supposed to interrogate people who are guilty. I'm supposed to ask you things as if I knew without a doubt in my mind you are guilty."

Two years ago, in Police Chief Magazine, Trainum wrote an article that outlines how an innocent person under interrogation can willfully admit to a crime (s)he didn't commit. First, interrogations are high pressure. An officer might ask 30 questions, Trainum said, and get 29 wrong answers, but what counts is the one that's right—or close. Next, police can lie. They can tell a suspect they have their fingerprints, or witnesses putting them at the crime scene, or DNA that matches—moves intended to put suspects on the defensive and get them to reveal details about the crime that no one but the criminal would know. But this second approach involves officers letting important details slip out—deliberately or accidentally—during interrogation; details known only to the police and the culprit.

The suspect, in this case Sanford, under a barrage of questioning feels compelled to confess to a crime he didn't commit. 

"Basically, we create a situation where you are faced with what you perceive to be an inevitable consequence," Trainum said, placing himself in the suspect's position. "He's telling me, 'I have all this evidence and they have these witnesses. He's telling me I'm going to be found guilty no matter what. I'm screwed. But he's also telling me that if I confess he's going to help me. I can go home. That this will go away. I just need to tell him what he wants to hear."

In fact, it was a false confession that Trainum owes to his current path of educating officers on correct interrogation techniques. In 1994, he worked a case where someone had been bound, beaten to death, then dumped in D.C.'s Anacostia River. His main suspect was a 19-year-old homeless woman, who confessed after a 17-hour interrogation. The District later dropped the charges, because it couldn't have been her. So why then, Trainum wondered, had she confessed? When he listened to the recording of the interrogation, he heard himself accidentally pointing her toward answers, revealing the hold-back information only the murderer--and police--could have known. When she parroted this back in conversation, it seemed like she must be the murderer. The reason he was so blinded, he said, was because most officers are taught an interrogation is supposed to elicit a confession, not to learn about the case. 

"Think about it," Trainum told me. "I'm convinced that you're guilty, so everything that you say, everything you do, is going to be perceived through that guilt-presumptive lens. Think about the way the interrogation process is structured--I've already determined the truth before I go in there, so what I'm trying to do is verify the way I perceive things to be, to what I think the truth is."

In 2013, the woman was asked on This American Life why she confessed to a crime she didn't commit. After 17 hours, she said, "I was tired. I figured I'd give them something and maybe they'd let me go home."

I also spoke with Megan Crane, a co-director at the Center on Wrongful Convictions of Youth at Northwester University, who said it's uncanny how similar victims of false confession sound. At some point, they just break down and want to leave. In Sanford's case, he seemed to have little concept of the repercussions of confessing to murder. In a story in The New Yorker, Sanford told the reporter he remembered sitting in the interrogation room, thinking he should just do what the officer wants.

 "I wanted everything to be right," he said, "because if it wasn't right, he wasn't going to believe me and he would keep me longer. I really wanted to go home." 

A month after Sanford was sentenced to up to 90 years in prison, Smothers, the hitman, sat in a Detroit interrogation room. One of the officers there was Sergeant Russell, the same man who'd interrogated Sanford. When Smothers confessed to the Runyon Street murders, he recalled, Russell "looked flabbergasted."

Then Russell told Smothers a teenager had already admitted to the four murders. It would take nearly a decade--until this Wednesday--for the state to believe it could have pressured Sanford into a false confession. But when he heard that Sanford confessed, Smothers remembered saying, "Wow, that's really messed up."