A New York man was officially exonerated on Tuesday 47 years after he was found guilty of rape in 1976 — the longest-standing wrongful conviction to be overturned based on new DNA evidence in U.S. history, the organization said.

A DNA hit "conclusively excluded" Leonard Mack, 72, as the perpetrator, Westchester County District Attorney Miriam E. Rocah said in a statement. Conviction Review Unit investigators identified a convicted sex offender after they ran the DNA through databases, and the DA's office said the individual has now confessed to the rape. 

"This exoneration confirms that wrongful convictions are not only harmful to the wrongly convicted but also make us all less safe," Rocah said. 

Mack, who served seven and half years in prison for the crime, said, "I never lost hope that one day that I would be proven innocent."

On May 22, 1975, police pulled over Mack in Greenburgh, New York, two and half hours after two teenage girls were stopped as they were walking home from school. One teen was violently raped. The other teen broke free and ran to a nearby school where a teacher called the police. The attack happened in a predominantly White neighborhood. The Greenburgh Police Department had put out a call for Black male suspect in his early 20s, the statement said. 

Mack, who is Black, was driving through the neighborhood at the time, and even though he was wearing different clothes than the suspect and had an alibi, he was brought into the police station. 

The Innocence Project said racial bias was a factor in police honing in on Mack and not investigating other potential suspects. Black Americans are more than seven times more likely to be convicted of a serious crime and then exonerated than White Americans, researchers found in a 2022 National Registry of Exonerations report. The Death Penalty Information Center found that exonerations of Black people for murder convictions are 22% more likely to be linked to police misconduct.

The victims identified Mack in a series of "problematic identification procedures," said the Innocence Project, explaining that victims were led through different photo arrays and lineups in which the material wrongly suggested Mack was the perpetrator. Eyewitness misidentification is the leading cause of wrongful convictions, with 70% of wrongful convictions happening due to witnesses picking out the wrong perpetrator. The Innocence Project said eyewitness misidentification has contributed to 64% of their 245 exonerations and releases.

At the trial, prosecutors presented flawed forensic testimony, the Innocence Project said. The medical examiner tested crime scene evidence at the time and found Mack was not a match, but prosecutors didn't present this information at trial and instead rebutted the findings and cast doubt upon them, the Innocence Project said.

Susan Friedman, a senior staff attorney at the Innocence Project who represents Mack, told CBS News, "Considering the unreliability of the witness identifications and the forensic evidence, the State's decision to continue the prosecution instead of reopening the investigation demonstrates the power of tunnel vision and the role that racial bias plays in the criminal legal system."  

In 2022, the Innocence Project approached the district attorney's office for assistance. The victim's underwear cuttings were sent to the lab for modern DNA testing, and after determining that Mack wasn't the perpetrator, a hit in the DNA database led them to a habitual sexual offender. That individual was convicted of a burglary and rape in Queens that occurred weeks after this crime. He also had a 2004 conviction for burglary and sexual assault of a woman in Westchester County, the Innocence Project said. 

Mack, who has been living in South Carolina with his wife for 21 years, said, "Now the truth has come to light and I can finally breathe. I am finally free."

In:
• Wrongful Convictions
• DNA
• New York

Cara Tabachnick is a news editor for CBSNews.com. Contact her at [email protected]