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For people trying to get out of prison for crimes they say they didn't commit, 2013 was a very good year, a record year for exonerations. More people were released after being cleared of crimes than any previous year. A report out this morning adds a detail. In past years, many people were freed thanks to DNA testing of evidence.
That still happens, but another factor is growing. The people who put convicts in prison, think again. Here's NPR's Laura Sullivan.
LAURA SULLIVAN, BYLINE: At least 87 people were cleared in crimes they did not commit last year, according to statistics compiled by the National Registry of Exonerations. That's the highest number in more than two decades since researchers began keeping track. In some of those cases, people spent decades in prison.
SAMUEL GROSS: It's taken a while for people to begin to believe these unfortunate and very distasteful facts.
SULLIVAN: Samuel Gross is a University of Michigan law professor who edits the registry, a joint project between the law schools at Michigan and Northwestern University. But Gross says don't just look to DNA, look to the prosecutors and the police.
GROSS: The number of exonerations where police officers and prosecutors have initiated the process or cooperated in the process has grown dramatically.
SULLIVAN: Only a fifth of the exonerations last year relied on newly tested DNA. More than a third occurred because law enforcement reopened a long-closed case or handed over their records to someone else who wanted to take a look. Gross says that's a sea change from just 10 years ago.
GROSS: The sharp cold shower that DNA gave to the criminal justice system has made us realize that we have to re-examine other cases as well. That was a serious wake-up call because that showed we made mistakes in a lot of cases where it never occurred to anybody that a mistake had been made.
SULLIVAN: Nowhere is that change more visible than in district attorneys' offices across the country. New York, Dallas, Chicago, Los Angeles and others have opened what are called conviction integrity units. These units' sole function is to review old cases and make sure the agency got it right.
SCOTT BURNS: We always did that, we just didn't call them something.
SULLIVAN: Scott Burns is executive director of the National District Attorneys Association. He takes issue with the idea that state prosecutors are more willingly reviewing old cases.
BURNS: We always reviewed big cases, multiple murders or high-profile cases. What you're seeing now is that it's institutionalized, it's given a name, probably a line item on a budget in a large office, and that's good as well.
SULLIVAN: There are 2,500 district attorney's offices across the country. Burns says many, if not all, would be happy to have such a unit. But in most cases it's not possible.
BURNS: There's hundreds of them that have one and two-women men offices. The review team would be, how do you think I did? I think I did really well. Okay. I mean you've got one person in the office.
SULLIVAN: Burns says while there may be more review happening, there is also simply more attention paid to wrongful convictions. He says it rarely makes news when prosecutors willingly test DNA in an old case and it turns out the offender was guilty. Still, he says being open to reexamining old cases is good for prosecutors because it builds public trust.
BURNS: Anything we can do to insure the integrity of a conviction is a positive and good thing and we're for that.
SULLIVAN: That's going to become more important in coming years as the number of exonerations based DNA evidence decline. These days, if there is DNA to test, it's matched or not matched to a suspect long before anyone sees a courtroom. Laura Sullivan, NPR News, Washington.