A Philadelphia man convicted of murder nearly a quarter century ago may soon see freedom after courts have found that the evidence used against him in 1993 does not support his conviction.

Shaurn Thomas, 43, was exonerated of a conviction stemming from a 1990 slaying of a Puerto Rican businessman named Domingo Martinez. Mr Martinez was shot while taking $25,000 to a check-cashing store that he owned.

Mr Thomas had an alibi from the start but his attorney wasn’t able to sway a jury. The case was picked up by the Philadelphia Innocence Project about a decade ago, and Mr Thomas’ exoneration represents the first time that a major action has been undertaken by an overhauled Conviction Review Unit in the Philadelphia district attorneys’ office.

“It’s going to be a good day,” Stephonia Long, Mr Thomas' fiancee, told Philly.com. “Everyone is very happy.”

Mr Thomas’ defence team and the Conviction Review Unit were able to locate the long-missing folder for Mr Martinez’s murder last month, and discovered that there was information regarding alternate suspects that weren’t presented to the original prosecutors or defense attorneys representing the case.

“It’s a great feeling,” James Figorski, a former Philadelphia police lieutenant who worked on Mr Thomas’ defence, said of the hard work paying off.

The United States has experienced record levels of exonerations in recent years. There were 166 exonerations in 25 states in 2016, according to the National Registry of Exonerations compiled by the University of Michigan. That included 54 homicide exonerations, 24 exonerated on sex crimes, 15 exonerated for violent crimes, and 73 exonerated for non-violent crimes.