A forensic pathologist has told a Quebec cold case murder trial that the 19-year-old victim died of strangulation. Guylaine Potvin, shown in a Quebec provincial police handout photo, was found dead in her apartment in Jonquière, Que., on April 28, 2000. THE CANADIAN PRESS/HO-Surete du Quebec **MANDATORY CREDIT**

A 19-year-old Quebec woman who was killed in her apartment nearly 24 years ago suffered multiple injuries and ultimately died of strangulation, a pathologist told a jury on Tuesday.

Dr. Caroline Tanguay took the stand in the Saguenay, Que., murder trial of Marc-André Grenon, who is charged with the first-degree murder and aggravated sexual assault of Guylaine Potvin.

Potvin was found dead in April 2000 in her apartment in Jonquière, now part of Saguenay, some 215 kilometres north of Quebec City. The trial has heard that Grenon, who has pleaded not guilty, was arrested 22 years after the crime, after DNA on two drinking straws he had discarded was allegedly found to be a match with evidence from the crime scene.

Tanguay, who did not conduct the autopsy on Potvin, said the injuries to the junior college student's body included blunt trauma to her head and shoulder, a bite mark on her left breast, and injuries to her neck and genital area.

Referring to the original pathologist's report, notes and photos, Tanguay concluded that Potvin died of "asphyxia from compression, seemingly a combination of manual strangulation and ligature strangulation."

On the witness stand, the pathologist was shown a belt with a broken buckle that was found next to the victim's body; she said it could have caused some of the marks on Potvin's neck.

"A belt could cause these kinds of injuries," she told prosecutor Pierre-Alexandre Bernard.

Tanguay said the original pathologist requested that DNA samples — including hairs and "secretions" that could be bodily fluids — be taken from several parts of Potvin's body for testing.

She said Potvin was found wearing only a T-shirt, with an imprint on her right hand that suggested a ring had recently been removed.

The trial, which began last week, is expected to shed light on the DNA research techniques that led investigators to arrest Grenon in 2022.

Bernard has said that while male DNA was discovered at the crime scene, there was no match in the police database and no witnesses to the crime. The suspect was eventually tracked down with the help of a project led by the provincial forensics lab that matches DNA with male surnames, the Crown said last week.

Earlier this week, the trial heard that partial fingerprints found at the scene could not be linked to Grenon. As well, the bite mark found on the victim’s breast could not be linked to the suspect, whose mouth had changed because of dental work in the intervening years, the defence and prosecution said in an agreed statement.

Quebec Superior Court Justice François Huot told the jury that these findings do not exclude the possibility that Grenon was at the scene but could not be used to implicate him.

Tanguay's cross-examination began Tuesday afternoon, but the case was adjourned until Wednesday following discussions between the lawyers and the judge.

This report by The Canadian Press was first published Jan. 23, 2024.

— By Morgan Lowrie in Montreal

News from © The Canadian Press, 2024