A record number of individuals were exonerated during 2013, and fewer of those cases hinged on DNA evidence than in the past, according to a survey released on Tuesday.

The National Registry of Exonerations—a joint research project of the University of Michigan Law School and the Center on Wrongful Convictions at Northwestern University School of Law—was behind the report. The team released its first annual report on exonerations in 2012.

It defines exonerations as cases in which an individual who is deemed wrongfully convicted is cleared of all charges based on new evidence of innocence.

During 2013, 87 convicted individuals were exonerated—more than in any year since 1989, when DNA evidence was first used successfully to challenge a conviction. Since then , at least 1,300 prisoners have been exonerated, according to the registry.

As has been the case for the past several years, the number of exonerations due to DNA evidence declined, representing only 28 percent of the cases. But exoneration for reasons other than DNA evidence doubled.

“It hasn’t disappeared. But the number has plummeted and been sliding down slowly,” Samuel Gross, a professor at the University of Michigan Law School and editor of the registry, said of the raw number of DNA-related exonerations. “At the same time, the number of exonerations in which DNA evidence plays no role has gone up dramatically.”

He attributed the change to the limited number of cases in which an individual’s DNA wasn’t taken at the time he or she was convicted. In recent years, investigators have gathered DNA samples, particularly in rape cases, making wrongful convictions less likely.

Gross cited another trend in the report: The increased involvement of law enforcement—prosecutors, police officers and judges—in investigating whether an individual might have been falsely convicted. In 2013, law enforcement got involved in 33 exonerations.

“That may be the beginning of the biggest change, because police and prosecutors are the most important actors in the criminal justice system,” he said.

The report cites the case of David Ranta, an unemployed house painter convicted in 1991 of murdering Rabbi Chaskel Werzberger in Brooklyn, N.Y.

Ranta was exonerated last year after the Kings County, N.Y., district attorney’s office uncovered new evidence that police had pressured and bribed witnesses to testify against him. The lead detective on the case, Louis Scarcella, has publicly defended his actions. “David is guilty of felony murder,” he told The New York Post. “He is not this innocent guy. He confessed.”

The report also found that in 2013:

♦ A record 15 exonerations occurred in cases in which the defendants had pleaded guilty.

♦ A record 27 exonerations came in cases in which new evidence established that no crime had in fact occurred.

♦ The state with the highest recorded exonerations was Texas, with 13.

♦ Exonerations involving homicide and sexual assault convictions represented the majority of cases but continued to drop—78 percent in 2013, down from 80 percent in 2012.

♦ By race, 47 percent of exonerated people were black, 40 percent were white, 11 percent were Hispanic and 2 percent were Native American or Asian.

Contact Amanda Bronstad at abronstad@alm.com.

Image: National Registry of Exonerations