CINCINNATI (AP) - A man who was exonerated after spending 13 years in prison for murder cried as a federal jury found that two police detectives violated his civil rights by coercing and falsifying testimony and withholding evidence that pointed to his innocence.

The jury's verdict on Friday, which included awarding US$13.2 million (S$16.5 million) to David Ayers of Cleveland for his pain and suffering, brings an end to the legal battle he's been fighting since his arrest in the 1999 killing of 76-year-old Dorothy Brown.

Mr Ayers, 56, was released from prison in 2011 after the 6th US Circuit Court of Appeals in Cincinnati reversed his conviction and the state decided not to seek another trial.

Mr Ayers, who was a security guard for the Cuyahoga Metropolitan Housing Authority, had been found guilty of killing Ms Brown at her CMHA apartment in Cleveland. She was found bludgeoned to death, covered in defensive wounds and naked from the waist down; she also had been robbed. DNA testing later proved that a pubic hair found in her mouth did not come from Mr Ayers.

"This should have been stopped a long time ago," Mr Ayers told the Cleveland Plain Dealer newspaper after the jury's verdict Friday. "My goal is that it never happens to anyone else ever again."

Mr Ayers filed his civil rights lawsuit in March 2012 against six Cleveland police officers, the city and the county housing authority. Allegations against three of the officers, the city and the housing authority were dismissed by a judge who found that their roles did not violate Mr Ayers' rights.

One of the remaining officers settled out of court with Mr Ayers for an undisclosed amount. The Friday verdict was against Michael Cipo and Denise Kovach, who were the lead investigators in the case.

Kovach and Cipo could not be reached for comment. They have denied misconduct.

Phone and email requests for comment with Cleveland police and the three city attorneys who represent Cipo and Kovach were not immediately answered on Saturday.

The Cleveland Plain Dealer reported that attorney Rachel Steinback of Chicago, who represented Mr Ayers, said the city is self-insured so the award will come from taxpayer money, not an insurance company.

Among the most serious allegations by Mr Ayers against Kovach and Cipo were that the two detectives conspired with each other to fabricate a confession that he never made, coerced a friend of Mr Ayers to lie by saying that Mr Ayers had told him of the murder before Ms Brown's body was discovered, and gave key information about the crime to Mr Ayers' prison cellmate so he could later testify against Mr Ayers about an admission he didn't make.

In an August filing, Cipo and Kovach argued to have the lawsuit dismissed, saying that they acted in good faith and with probable cause, and that Mr Ayers was responsible for any alleged injuries that he incurred.

Federal Judge James Gwin denied their request late last month shortly before the trial, ruling that Mr Ayers had produced sufficient evidence that the detectives had violated his rights.