A timeline in the case against former Akron Police Capt. Douglas Prade

Former Akron Police Capt. Douglas Prade is the only Ohio inmate once freed by DNA testing before being re-imprisoned.

Prade was convicted of killing his ex-wife, Dr. Margo Prade, in 1997. He has since said he didn't commit the crime. Here is a timeline of events in the case.

Nov. 26, 1997: After Dr. Margo Prade failed to show up to her clinic to treat patients, a staff member finds her dead in her minivan in the clinic's parking lot. An autopsy finds she was shot six times and her killer bit her through her blouse and doctor's coat, leaving a curved bruise on her upper left arm.

Accused:Ohio man once considered exonerated by DNA evidence still fights to clear name

Winter 1997: Investigators recover surveillance footage from a neighboring business that captured the killing but is too pixelated to be useful for identification purposes. The FBI joins Akron police in the investigation. On Dec. 1, Douglas Prade passed a lie-detector test prompting the Cleveland Plain Dealer to run a story headlined: EX-HUSBAND CLEARED IN PRADE CASE.

Feb. 23, 1998: Douglas Prade is arrested and charged in his ex-wife's murder. The top evidence police gave reporters at the time was that the bite mark on Margo Prade's arm was deemed to have matched Prade's teeth, per a New York odontologist.

September 1998: Douglas Prade is tried in Summit County Common Pleas Court. Prosecutors paint him as financially strained and suggest the $75,000 life insurance policy he received after Margo Prade's death was motive for murder. Prosecutors also emphasized two odontologists' testimony that the bite mark left on Margo Prade's arm supposedly matched impressions taken of Douglas Prade's teeth.

Sept. 23, 1998: Prade's convicted of murder and wiretapping – the latter related to audiocassettes he had of his ex-wife talking on the phone with others. Prade was sentenced to life in prison. "I didn't do this," Prade said in the courtroom. "You convicted the wrong man."

1998-2008: Prade's various appeals fail up through the 9th District Court of Appeals. The Ohio Supreme Court refused to hear the case as well. Prade also filed applications for post-conviction DNA testing, which initially were denied. Meanwhile, convictions based largely on bite-mark evidence start falling under scrutiny as it's determined human skin is too malleable to reliably compare with dental impressions. The National Academy of Sciences publishes a report in 2009 stating dentists are not able to identify perpetrators of crimes by matching dental patterns to marks on victims' bodies.

Aug. 31, 2009: Barry Scheck's Innocence Network in New York files a defense brief on Prade's behalf arguing that new DNA testing is vital because a negative result could conclusively prove Prade's innocence.

May 4, 2010: The Ohio Supreme Court reconsiders and sends the case back to the trial court to weigh whether DNA testing should be allowed after all.

Sept. 23, 2010: Summit County Judge Judy Hunter agrees to the testing, which ultimately focuses on the doctor's coat Margo Prade was wearing when she was killed. Both prosecutors and defense lawyers agreed the doctor had been bitten hard enough to leave an impression on her arm, so they considered the corresponding area of her coat as key.

August 2012: DNA tests on biological matter recovered from Margo Prade's coat indicate the presence of two male profiles, neither of which were Douglas Prade. Summit County Prosecutors argue the new evidence is "meaningless."

October 2012: A days-long hearing is held in Summit County court as Prade argues he should be granted a new trial. Forensic odontologist Franklin Wright testifies that bite-mark analysis classified in 1998 as showing Prade's bite matched the mark on Margo Prade's body would by modern standards be considered "inconclusive."

Jan. 29, 2013: Judge Judy Hunter rules that the DNA testing and changes in how bite-mark evidence is weighed would likely mean a modern jury would not find Prade guilty. Hunter's ruling also included a conditional order for a new trial if her findings were overturned. She orders Prade's release from prison. He'd been behind bars for 15 years.

February 2014: Prade alleges a conspiracy among Akron Police Department investigators, accusing them of framing him of murder.

April 2014: The 9th District Court of Appeals rules that now-retired Judge Hunter erred in freeing Prade, saying that the DNA results raised more questions than answers. Prade was allowed to remain free on bail while he appealed to the Ohio Supreme Court.

July 2014: In a 4-3 decision, the Ohio Supreme Court declined to hear Prade's appeal of the 9th District's ruling. Prade, who had spent 18 months reconnecting with family, was ordered back to prison by Judge Christine Croce, who opted not to honor Judge Hunter's earlier provisional ruling that called for Prade to be granted a new trial if her order was ultimately overturned.

March 2017: Croce denies Prade's continued requests for a new trial, saying he had "failed to introduce any new evidence that the jury had not already considered" in his '98 trial. The 9th District Court of Appeals eventually concurs.

March 2019: The Ohio Supreme Court declines to hear Prade's case again. His lawyers with the Ohio Innocence Project hit a dead end in their efforts to free him.