By Ed Brock

New DNA evidence just freed another Georgia man who was wrongly convicted of a crime, and officials say there could be many more.

Clarence Harrison, 44, of Decatur, was sentenced to life in prison in 1987 on charges of sexually assaulting a hospital employee as she waited for a MARTA bus. On Monday Harrison became a free man thanks to DNA evidence gathered and tested by the Georgia Innocence Project, an organization dedicated to exonerating the falsely accused with such evidence.

"I feel good. Happy to be out," said Harrison, who is now staying with his fianc?e in Marietta, looking for a job and hoping to get married.

But the work is far from over for the GIP. Of the 1,400 requests the GIP has received since they were formed in August 2002, they have only accepted seven, GIP Executive Director Amy Maxwell said. Two of the cases have been settled, one in which there was not enough evidence to exclude the man, and the other being Harrison's case.

Of the five remaining cases, they have only found original evidence in one case.

"Which is of course extremely disheartening for us," Maxwell said.

Still, the national Innocence Project, based in New York, has exonerated 151 falsely accused prisoners. And the GIP is also investigating another 250 cases for acceptance. They have their work cut out for them.

Maxwell said that according to the U.S. Department of Justice, 10 percent of the prison population for the entire country is innocent of the crimes for which they were convicted. Since Georgia has about 50,000 people in prison that would mean some 5,000 are innocent.

But in many of the cases DNA evidence is never collected in the first place. And Maxwell said that the biggest challenge for the GIP, which is staffed almost exclusively by law students volunteering their time, is finding what evidence might be left over from original court proceedings.

"Up until last year they could have thrown it away right after the case was finished," Maxwell said.

Last year the Georgia General Assembly passed the post-conviction DNA law, sponsored by Sen. David Adelman, D-DeKalb, that requires prosecutors to keep DNA evidence for at least 10 years after the trial. The law also allows inmates to petition for a retrial based on new DNA evidence if four conditions are met. Those conditions are that the identity of the defendant was an issue at the trial, that reliable results can be extracted from existing evidence, that it is reasonable to believe the DNA evidence would have affected the outcome of the original trial and that the evidence was not previously tested.

In Harrison's case, he applied for DNA testing of the rape kit in his case more than once and was told the sample was improperly stained. He had given up on the system by the time he learned about the GIP and sent them a letter.

"They responded really quickly and I felt confident in them after their response," Harrison said.

Harrison's release came about due to some very good luck as well as hard work, said former Clayton College and State University Professor Greg Hampikian. Hampikian, now a professor of biology and criminal justice at Boise State University, is still an adjunct professor at CCSU and co-authored the book "Exit to Freedom" with Clayton County resident Calvin Johnson Jr.

Johnson went through a very similar experience to Harrison's. He was also convicted of a rape he didn't commit and spent 16 years in prison before the national Innocence Project took his case and brought about his release.

Hampikian is on the GIP board and oversees their DNA testing.

To understand how lucky Harrison was one has to understand the science of DNA evidence that freed him. Hampikian said there are 15 "loci" on the human chromosome that allow for a DNA fingerprint to be made.

"If we get all 15, there's only one person in the world it belongs to or their identical twin," Hampikian said.

In one GIP case, for example, only three loci could be identified from the remaining evidence, which is not enough to exclude a person since that many loci can be shared between individuals.

It's like having an address for the suspect as being in Honolulu, Hawaii, Hampikian said.

"I can tell that the five billion people who don't live in Honolulu are excluded," Hampikian said.

In Harrison's case the evidence contained all 15 loci.

"Which on a 17 year old rape kit is pretty miraculous," Hampikian said.

In fact, the evidence is not only good enough to exonerate Harrison, it could lead to the arrest of the real perpetrator if he has been convicted of a felony that allows a sample of his DNA to be entered into a nationwide database, Hampikian said.

DNA evidence has become increasingly useful in the years since Harrison was arrested, said DeKalb County District Attorney Jeffrey Brickman who worked closely with the GIP in getting Harrison freed.

"If we had had that DNA evidence back in 1987 Mr. Harrison would not even have been charged," Brickman said.

Clayton County District Attorney Bob Keller, who was the original prosecutor on Calvin Johnson's case, helped to write the post-conviction DNA law.

"(DNA evidence) is the best identifier we have now. It removes all doubt of misidentification," Keller said.

DNA can prove who committed a crime as well as exonerating those who are innocent, Keller said. Cases like Johnson's and Harrison's underscore the need for the DNA law.

"In the Calvin Johnson case it was just lucky we kept the evidence," Keller said. "We now have a law mandating we keep it."

Keller's successor, Jewel Scott, also said she would give much consideration to DNA evidence when she takes office in January.

"(The legal process) is an inquisition to discover what the truth is," Scott said. "If there's not evidence to go forward then a person should not be charged."

Scott said she would always cooperate with the GIP on similar projects.

Harrison said he wants to keep working to increase donations to the GIP, because in his years behind bars he was not the only innocent man there.

"A lot of them in there were unjustly sentenced," Harrison said.

The Associated Press contributed to this article.