There were nearly seventeen hundred murders in New York City in 1987. One of the first occurred about ten minutes after the ball dropped in Times Square, when a group of young people mugged a seventy-one-year-old French tourist named Jean Casse, on West Fifty-second Street, outside Ben Benson’s Steak House. One young man punched the victim, and one or more rifled through his pockets. Casse fell, hitting his head on the sidewalk. He died ten hours later, at a hospital.

The New York City Police Department quickly set up a hotline and announced that it “desperately” needed “witnesses of the incident to come forward.” Officers were instructed to ask anyone arrested for robbery if he had information about the murder. On the afternoon of January 2nd, the police caught four young people mugging a man on West Forty-seventh Street. The group included James Walker, a sixteen-year-old from Brooklyn. While in police custody, Walker told a detective that earlier that day he had run into an acquaintance named “Smokey,” who had said that he’d “caught a body” in Manhattan on New Year’s Eve.

Walker went on to identify Eric Smokes and David Warren, two best friends who lived in one of Brooklyn’s poorest neighborhoods, East New York. Smokes was nineteen, and Warren was sixteen. They’d each had a minor run-in with the law: Smokes had been arrested and fined for shoplifting, and Warren had been arrested for a mugging. (Warren’s case was later dismissed.)

On January 3rd, Smokes and Warren were questioned separately by detectives, and both said that they had gone to Times Square with friends on New Year’s Eve; a few hundred thousand people had packed the streets. Smokes and Warren had ended up on West Forty-eighth Street, outside the Latin Quarter, a night club popular with teen-agers. Warren recalled, “We didn’t have the funds for that, so we stood around for a little while” before heading south. Smokes said that, around West Thirty-eighth Street, he “saw some people fighting and saw some guy that got shot.” When the bullet hit, feathers flew out of the man’s jacket. Both Smokes and Warren said repeatedly that they had not gone north of Forty-eighth Street. According to the police report of Smokes’s interrogation, “Mr. Smokes states he did not see any old man get mugged.”

The police released Smokes and Warren, but arrested them five days later. Smokes watched from the back seat of a police cruiser as detectives brought his friend out of high school in handcuffs. “From the point that we got to his school, the reality of it really hit,” Smokes told me. “He looked at me as a big brother, and I looked at him as my little brother, and there was nothing I could do to help my little brother.” He added, “I couldn’t comfort him in no way except to say that we’re in this together.”

They were sent to Rikers Island, where they were placed in separate housing units. “They took me from high school to jail,” Warren told me. “It was like a dream that I just couldn’t wake up from.” Six months passed, and prosecutors offered Warren various plea deals: if he testified against Smokes, he would receive a very short prison sentence. Warren refused. He explained, “I’m not going to say he did something I know he didn’t do.”

That summer, Smokes and Warren were tried for murder in New York State Supreme Court, in Manhattan. Prosecutors accused Smokes of punching Jean Casse and Warren of trying to rob him. The prosecution’s star witness was James Walker, who had signed a coöperation agreement with the Manhattan D.A.’s office; prosecutors promised that if he testified “truthfully” they would not send him to prison for the January 2nd mugging. Walker testified that he had committed robberies with Smokes and Warren in the past, and repeated his claim that Smokes had told him that he had “caught a body.” Smokes and Warren insisted that these claims were untrue. But prosecutors also relied on four other young men, who claimed that they had seen Smokes and Warren at the crime scene. Smokes knew one of them, but the others, he said, were strangers.

The daily papers had covered the Casse murder, which may have exacerbated tensions in the courtroom. The jury, before delivering its verdict, sent a message to the judge, saying, “We would like the Court to know that we did not come to a decision lightly but with great emotional turmoil.” They voted to convict both teen-agers of second-degree murder. After the trial ended, Warren, in a state of disbelief, remained in his seat. “I had to tap him and say, ‘Come on,’ ” Smokes told me. “It didn’t register that he was found guilty.”

The judge, Clifford A. Scott, was known as one of the toughest judges in the city, and had embraced the nickname Maximum Scott. He sentenced Smokes to twenty-five years to life in prison and Warren to fifteen to life. At their sentencing hearing, Smokes declared, “I have been framed!”

In 2005, when Eric Smokes had been in prison in upstate New York for eighteen years, he received a letter from James Walker. When Smokes saw the name on the envelope, he said, he thought “it might be a pipe bomb or something.” But the letter was an apology. “I was basically giving the police & DA what they wanted after I heard what they was looking for,” Walker wrote. He added that he had been “strung out on crack” and “not thinking straight.” Smokes, with assistance from a friend in prison, drafted a memo on his case and sent it, with copies of Walker’s letter, to every lawyer and legal clinic he thought could help. Two years after Smokes had been sent to prison, the Manhattan D.A.’s office had charged five teen-agers in connection with the rape of a jogger in Central Park; in 2002, they were exonerated after a serial rapist confessed to the crime. Smokes’s memo stated, “Like the suspects in the Central Park Case, David and Eric’s arrest resulted from police investigation conducted under public and political pressure to hold someone responsible.” No lawyer agreed to take his case.

In 2007, Warren returned to Brooklyn. Four years later, Smokes was released. “When I came home, I said, ‘I got to do something,’ ” he told me. “I can’t stand by idly and just accept the fact that I did twenty-five years for a crime I didn’t do.” He eventually found two attorneys, Craig Phemister and James Henning, who were willing to take on the case pro bono. The lawyers tracked down Walker and other people who had spoken to the police during the 1987 investigation, including Kevin Burns and Robert Anthony, two of the men who said they’d been at the crime scene. Burns, Anthony, and Walker all signed affidavits saying that they had given false testimony under pressure from law enforcement.

In February, 2017, Phemister and Henning met with prosecutors in the Conviction Integrity Program of the Manhattan D.A.’s office. The District Attorney, Cyrus Vance, Jr., had established the program, in 2010, to prevent wrongful convictions and to investigate claims of innocence. Henning, a recent law-school graduate, explained why he believed his clients had been wrongly convicted. The prosecutors from the Conviction Integrity Program, he later recalled, seemed “guarded and defensive.” One of them had sent him a police report that he’d requested, but when he asked for other documents the prosecutors refused to share them. “The fact that they didn’t want to give me anything, but they wanted everything from me, it put up red flags for me,” Henning said.