TORONTO -- An Ontario man will be tried for a fourth time in September 2016 in the murder of a nursing assistant who was killed 33 years ago in the Hamilton area.

Diane Werendowicz died in 1981. She was dragged into a ravine, allegedly sexually assaulted, strangled and dumped in a creek.

Robert Badgerow was arrested in her death in 1998 and was convicted of first-degree murder several years later, but the verdict was overturned on appeal.

A new trial was ordered but ended in a mistrial in 2010 when a jury was unable to reach a verdict. Badgerow's third trial also resulted in a hung jury.

He then applied for, and was granted, a stay of proceedings when the Crown indicated it intended to try him for a fourth time. That stay was set aside by Ontario's Court of Appeal in April, and a new trial was ordered.

Badgerow then tried to take his case to the country's highest court, but the Supreme Court of Canada denied his leave to appeal.

Consequently, a date for his trial was set last week in a scenario his lawyer admits is atypical.

"It's unusual, but the court has ruled that he's to have a fourth trial," said Russell Silverstein.

In ordering that a fourth trial should proceed, the Ontario Court of Appeal noted that "highly probative and admissible evidence" was excluded at previous trials, so the Crown hasn't had a full opportunity to put its case before a jury.

"Notwithstanding the challenges associated with conducting a trial after the passage of almost 35 years, there is a strong public interest in a trial on all the legally admissible evidence and this swings the balance against a stay," the Appeal Court wrote.

The evidence that was previously excluded from the earlier trials is regarding a 911 call from a pay phone, possibly placed by the killer and traced to a location near Badgerow's workplace.

Court documents have noted that 23-year-old Werendowicz had worked as a nursing assistant at the McMaster University Medical Centre. In June 1981, she and another woman went to a bar in Stoney Creek, in the Hamilton area, after work and had a few beers. She left the bar alone around midnight to walk to her home, which was about 15 minutes away.

On her way home, court documents have said Werendowicz was dragged into a ravine, sexually assaulted, strangled, dumped in a creek and drowned. When her body was found later that day a tire covered her head and shoulders. When it was lifted, it was discovered she had been strangled, with the strap of her purse wound around her neck.

Badgerow, who had been arrested in 1981 in connection with the "brutal assault" of a different young woman in the same area, was identified as a suspect in Werendowicz's killing in the late 1990s.

Police surreptitiously obtained a sample of Badgerow's DNA and it matched the profile from semen found in Werendowicz's body, court documents have said.

At his trials, Badgerow maintained he had consensual sex with Werendowicz in the back of his truck outside the bar the night she died and that someone else must have attacked her on her way home.