RALEIGH, N.C. (AP) – Fifteen hours after Troy Davis was executed, two men walked out of a North Carolina prison after being exonerated of a murder they had pleaded guilty to committing more than 10 years ago.

The difference, legal experts and observers say, is largely explained by a one-of-a-kind system for examining innocence claims that the state launched in 2005. That process is what freed Robert Wilcoxson and Kenneth Kagonyera from a lockup in Asheville.

“If Georgia had the North Carolina Innocence Inquiry Commission, I believe Troy Davis today would be free instead of dead,” said Mark Rabil, a defense lawyer and co-director of the Innocence and Justice Clinic at the Wake Forest University School of Law.

Prosecutors, though, say that wrongful convictions are rare and that they work carefully to make sure innocent people never are charged in the first place.

Davis was executed Wednesday for the 1989 murder of off-duty Savannah police officer Mark MacPhail. Defense attorneys said several key witnesses disputed their testimony and other people claimed that another man confessed to the crime, but state and federal courts repeatedly upheld the conviction. His case garnered worldwide attention, with celebrities, the pope and former President Jimmy Carter among his supporters.

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In North Carolina, the state commission examines claims like those made by Davis — who maintained his innocence even when he was strapped to a gurney in Georgia’s death chamber. If cases meet rigorous criteria, they are reviewed by a three-judge panel that can reverse a conviction only if the decision is unanimous.

Wilcoxson and Kagonyera said they had pleaded guilty to the 2000 murder of Walter Bowman during a home invasion robbery to avoid possible death sentences. The judges determined DNA and other evidence exonerated the men. Testimony showed a different man confessed to a federal agent.

The exonerations are especially significant because the two men struck those plea deals. Prosecutors have proposed a bill — to be considered next year — that would prevent those who plead guilty from coming before the innocence commission. The only other man freed by the commission, Greg Taylor, maintained his innocence throughout the 17 years he spent in prison. A jury convicted Taylor, who had pleaded not guilty.

“This is a testament to the need for an innocence commission project, and to the fact that people can be not guilty even if they plead guilty in court,” said Christine Mumma, director of the North Carolina Center on Actual Innocence, which advocates for convicts seeking exoneration.

Prosecutors also wield a big stick when they threaten a defendant with the death penalty. Of the 273 people exonerated by post-conviction DNA testing in the U.S. since 1989, the death penalty was threatened or imposed in 46 cases, said Stephen Saloom, policy director of the New York-based Innocence Project. Of 14 threatened with the death penalty, 13 confessed or pleaded guilty.

Another 15 faced possible death sentences but either were convicted of a lesser charge or received a different sentence. In the other 17 cases, people were sentenced to die before post-conviction DNA evidence proved their innocence.

And some states don’t allow courts to consider exonerating DNA evidence when defendants have pleaded guilty, Saloom said.

In the case of Kagonyera and Wilcoxson, prosecutors had DNA evidence excluding them even before they pleaded guilty. But defense attorney Sean Devereux said he wasn’t aware of it. Buncombe County District Attorney Ron Moore has said he doesn’t know why the defense didn’t get the information.

Rabil said the case will show how much the threat of capital punishment can distort the criminal justice system.

“When the odds are stacked against you because of the death penalty, the lawyers, the people in the cases, out of fear of the unfairness of the death penalty trial, will do everything they can do within their powers, ethically, to convince someone to plead guilty,” Rabil said. “I’ve done it myself.”

But prosecutors say that they regularly exonerate suspects and that appeals courts already serve the same function as the innocence commission.

Scott Burns, a former Utah prosecutor who now is executive director of the National District Attorneys Association, noted that Davis had two decades’ worth of appeals. He also pointed out that the U.S. Supreme Court granted Davis a rare hearing to prove his innocence.

“As a prosecutor it is so frustrating to have people say you executed an innocent man if you were there at the crime scene, you were involved in marshaling evidence with law enforcement, you were questioning witnesses throughout the investigation and making a determination about whether to proceed before you finally put the case before a jury,” he said.

Prosecutors aren’t always right, Burns said, but thousands of convictions are never challenged.

“With millions of cases across the country, every once in a while you get something wrong,” he said. “But that’s the one everyone hears about.”
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Copyright 2011 The Associated Press.