William Gregory still carries around the legal paperwork to prove he's not a rapist. Gregory served seven years behind bars before DNA (search) tests five years ago showed he couldn't have committed the crime.

He left prison with only a garbage bag filled with clothes and a television — and doesn't have much more today because Kentucky isn't one of the 19 states that allow wrongfully convicted people to seek compensation.

Now, Gregory is suing the prosecutors and police that handled the investigation leading to his conviction.

"I don't have savings, I don't have nothing for retirement," Gregory said. "That's bad."

Of nearly 160 people freed from prison by DNA tests since 1989, 17 have been financially compensated by the states that locked them up. The federal government also has a compensation law.

Only in a few cases have the amounts been made public: Ohio paid $250,000 to a man wrongly imprisoned 11 years for rape and Massachusetts paid $500,000 each to three men, whose time behind bars ranged from 14 to 19 years, for mistakenly convicting them of rape.

Compensation laws often make it difficult for a person who has been exonerated to collect any money, said Richard Dieter, executive director of the Death Penalty Information Center (search) in Washington.

Dieter pointed to Florida, where the law requires the Legislature to pass a bill awarding funds to the freed inmate, and North Carolina, where a pardon from the governor is required before a wrongly convicted person can become eligible for payments of $20,000 for each year spent behind bars.

But some prosecutors see a slippery slope once the state starts writing checks to people freed from prison.

Pete Adams, executive director of the Louisiana District Attorney's Association (search), points to the case of famed prison journalist Wilbert Rideau. An appeals court granted Rideau a new murder trial 40 years after the crime was committed. Rideau was convicted of manslaughter and sentenced to time served in prison.

But Adams points out that if the district attorney had not been able to assemble enough evidence to bring the case back to trial, Rideau would have been declared legally innocent and possibly entitled to compensation for his four decades in prison.

"The danger ... is that there is no logical line to draw between factually innocent cases and the Rideaus," Adams said.

In states with no compensation law, some found wrongly convicted, such as Gregory, have sued the prosecutors and police who handled the investigation leading to the conviction.

Those lawsuits have had mixed results. For example, Gregory's case against the city of Louisville and various police officers and investigators is on appeal after a judge dismissed parts of it.

Gregory was convicted in 1993 based in part on testimony that hairs found in a stocking worn by the attacker were consistent with his. He was sentenced to 70 years in prison for rape and two counts of attempted rape.

DNA tests were not available at the time, but became available in the late 1990s. With help from The Innocence Project, a nonprofit organization that pushes for DNA exoneration, Gregory successfully appealed to have the hairs tested. The tests showed the hairs could not have come from him.

He was freed after prosecutors opted not to retry him. No one else has been arrested in the case.

Louisville police spokeswoman Alicia Smiley said the department does not comment on pending litigation. In court filings, the city and police say Gregory has failed to make a case that police intentionally did anything wrong, and that they should not be held responsible for honest mistakes.

Gregory, who now works in the electronics department of a Louisville-area Best Buy store, is hoping to settle the case and use the money to start a foundation aimed at helping people who are in his position.

"Any money, it'll bring some comfort," he said, "but it won't bring back all those years."