CINCINNATI — A former Ohio police captain who has spent nearly 15 years in prison in his ex-wife’s killing was exonerated Tuesday by a judge who said that new DNA test results proved his innocence and that no reasonable jury would have found him guilty if that evidence had been available at trial.

Doug Prade should be set free because the new DNA results are “clear and convincing,” said Summit County Court of Common Pleas Judge Judy Hunter in Akron.

Hunter could have ordered a new trial for the 66-year-old Prade, or found that the DNA results weren’t strong enough and allowed his conviction and sentence of life in prison to stand.

It was not immediately clear when Prade would be released from the central Ohio prison where he has been jailed, and his attorney was not immediately available for comment, except to say in an email that she was “thrilled.”

“This has been a long time coming,” wrote attorney Carrie Wood, who works for the Cincinnati-based Ohio Innocence Project and has been working for years to get Prade freed.

Summit County Prosecuting Attorney Sherri Bevan Walsh vowed to appeal, saying in a statement that Hunter’s findings were “a gross misapplication of the law.”

“We have not seen any credible evidence that suggests innocence, and we are taking all available actions to keep a dangerous killer off the streets,” she said.

If a higher court should agree with prosecutors and overturn Hunter’s ruling, Prade would get a new trial.

Margo Prade, a 41-year-old prominent Akron doctor, was found slumped in her minivan outside her office on Nov. 26, 1997. She had been shot six times, but there were no witnesses and no fingerprints, and no gun ever was found.

The only piece of concrete evidence was a bite mark on her arm; the killer bit her so hard that it left an impression through her lab coat and blouse.

A forensic dentist testified for the prosecution that he was sure Prade was responsible for the mark, while a defense expert said that the defendant’s teeth couldn’t have left it. A third expert for the prosecution said there was no way to be certain that Prade made the mark but that it was consistent with his teeth.

Jurors found Prade guilty of aggravated murder after deliberating for six hours, and the 30-year veteran of the Akron police department was sentenced to life in prison.

The Ohio Innocence Project later intervened and successfully fought to get male DNA from around the bite mark tested. The test — conducted for free by the private DNA Diagnostics Center in Fairfield, Ohio — found conclusively that the DNA was not Doug Prade’s.

Prade’s attorneys said the new test, which wasn’t widely available at the time of his trial, proved his innocence. Prosecutors argued that the male DNA could have gotten on Margo Prade’s lab coat before or after she was killed. Further testing on other parts of the coat didn’t turn up any male DNA.

Hunter ruled Tuesday that the remaining evidence in the case would not be enough to convict Prade of murder, saying that much of it was “tenuous at best,” that the accuracy of two witnesses’ testimony was questionable and testimony about the Prades’ contentious divorce “is entirely circumstantial and insufficient by itself.”

In an interview with The Associated Press in August, Prade said that he hoped the results would be enough to free him.

“For them to find what I had known all that time was no surprise to me,” he said in a phone interview from prison. “I guess it was an epiphany to everyone else — ‘Hey, this guy was telling the truth.”’

In the years following Prade’s trial, bite-mark comparisons have come under fire as sham science. At least 11 prisoners convicted of rape or murder based largely on bite mark-comparisons were exonerated — eight of them with DNA evidence. At least five other men were proved innocent as they sat in prison awaiting trials.

Prade’s attorneys and prosecutors squared off at a four-day hearing in October and renewed their arguments in lengthy court documents in December.

“Prade has provided ‘clear and convincing’ evidence of his innocence, as well as that, had the new DNA and other evidence been introduced at trial, there would have been reasonable doubt such that no reasonable jury would have convicted,” Prade’s attorneys wrote.

Walsh, the prosecutor, argued that nothing Prade presented was clear or convincing and that “Prade is where the jury felt he belongs.”

“To contend … that not one reasonable fact-finder would find him guilty of aggravated murder is truly to enter the realm of the absurd,” she wrote.

Walsh also emphasized circumstantial evidence in the case, saying that Prade had tapped his ex-wife’s phone hundreds of times in the year before the killing and that he never signed a divorce decree, which would have stopped him from collecting a $75,000 life insurance policy.

Prade’s attorneys said their client used more than half the policy to pay of Margo Prade’s own debts and still had more than a fourth of it when he was arrested. They also say a contentious divorce and the phone tapping don’t prove anything.

Prade told the AP in August that spending more than 14 years in prison, mostly amid the general population, has been “hell on Earth.”

“I mean, it’s one thing if someone is guilty of something to be here, but to be not guilty and here is even worse,” he said.