All it takes is a touch. Tiny bits of DNA attach to cell phones, clothes, door knobs, and other surfaces, leaving a trace of the culprit at a crime scene. The data in that DNA could point to a killer–or could set someone free.

Over the past decade, the Georgia Innocence Project has exonerated five people imprisoned for years for crimes they did not commit. Four of those people were convicted of rape in the 1980s, before DNA testing was available. As the project marks its tenth anniversary this month, it has a much broader pool of people who may be able to prove their innocence.

“Now we’re able to get important evidence that nobody ever thought was going to be available to prove identity,” says executive director Aimee Maxwell. “That’s been a real revolution.”

Case in point is the fifth exonerated inmate: Michael Marshall, forty-five, was homeless and sleeping in an apartment hallway in Hapeville in 2007 when a police officer noticed his “uncanny similarity” to a sketch of a suspect who had stolen a truck at gunpoint. A victim identified him, and Marshall pled guilty to a lesser charge.

But Marshall later wrote the Georgia Innocence Project, saying he had only pled guilty because he was afraid of facing a long prison sentence. Then-law school intern Christina Rupp investigated his case and discovered police had evidence that could be tested for DNA – but had never tested it. A Hapeville officer had found and followed the stolen truck, and the thief jumped out and ran off, leaving behind a T-shirt, cell phone, and phone case.

When the Georgia Bureau of Investigation tested those items in 2009, they found that the DNA did not match Marshall. In fact, it matched another man with a prior criminal record. A judge ordered Marshall’s release in December 2009.

>> From the archives: Read Marill's feature "The Innocents"

With better DNA testing, the Georgia Innocence Project is looking into complex murder and arson cases, says Maxwell. For example, they discovered a glove in a Savannah case that has a touch DNA. “We found out who it matched and that’s going to be crucial as to whether our client spends the rest of his life in prison,” she says.

In its ten years, the Georgia Innocence Project has combed through 5,000 letters from prisoners who assert their innocence and taken on about thirty cases. While DNA testing could lead to many more investigations, the Georgia Innocence Project is also looking for ways to slow or stop the pipeline of faulty convictions.

Inaccurate eye witness identification has been an issue in each case that later led to exoneration, Maxwell says. The Georgia Innocence Project has worked to educate law enforcement about procedures that lead to more reliable eye witness information, she says.

“Our mission has expanded from getting innocent people out of prison to stopping wrongful conviction in the first place,” she says.