An ex-Marine was shot and killed while sitting in his car in Baltimore, Maryland.
After the shooting, police interviewed witnesses, including one woman, who claimed to have seen someone on a bike ride up to the victim's car and shoot him. When shown a photo array the “witness” identified a 19-year-old man as the shooter.
The witness was the main prosecution witness against the accused man when he went on trial before a judge who heard the case without a jury. The accused claimed he could prove that the witness was lying and could not have seen the murder from her apartment, but his attorney failed to investigate the crime scene.
The judge convicted the accused man of second-degree murder and possession of a handgun; he was sentenced to 30 years in prison. After the conviction, his appellate attorney requested the case file from the prosecution, and discovered exculpatory evidence that had not been provided to the defense.
The files showed that another witness, who viewed a photo lineup that included the accused man, had identified someone else as the shooter. The witness also said he saw the shooter ran away on foot, not on a bike as the female witness had claimed. And yet another witness gave the police a description that did not hold up to the first witnesses description and also said they saw someone running away from the scene, not on a bike.
The accused man’s lawyer and a PI interviewed the female witness and got her to confess that she had not seen the crime and was high on cocaine at the time.
While the accused man’s first motion for post-conviction relief was denied, he got a second chance years later when the Innocence Project of the Maryland Office of the Public Defender took on his case and filed a motion to reopen his post-conviction proceeding. That motion was granted and his conviction was vacated by a Baltimore City Circuit Court judge. He was granted a new trial and the prosecution dismissed the charges; he was released.
https://www.law.umich.edu/special/exoneration/Pages/casedetail.aspx?caseid=2985