The Crown concludes its evidence at the trial of Marc-André Grenon

Open in full screen mode

An illustration by Pierre-Alexandre Bernard, the representative of the criminal and penal prosecution department, at the trial of Marc-André Grenon.

• Mireille Chayer (View profile)Mireille Chayer

Voice synthesis, based on artificial intelligence, allows you to generate spoken text from written text.

The Crown's case is closed at the trial of Marc-André Grenon, the man accused of the murder and sexual assault of Guylaine Potvin in April 2000 in Jonquière.

Friday morning, the defense quickly finished the cross-examination of forensic biologist Caroline Paquet, whose testimony s was started on Wednesday.

The specialist once again explained that only two objects found in Guylaine Potvin's room contained a unique genetic profile, namely the box of condoms and the belt on which traces of blood were found.

In the other samples, there were combinations of DNA from the victim, but also from one or two other contributors. Ms. Paquet had clarified earlier this week that statistical calculations tend to demonstrate that it is billions of times more likely that the DNA present is that of Marc-André Grenon rather than that of someone else.

Open in full screen mode

Caroline Paquet has worked at the Laboratory of Forensic Science and Legal Medicine in Montreal since 2005 and became coordinator of unsolved biology cases since 2021.

Based on a report produced in 2022, the forensic biologist explained that new analyzes had been made. On the other hand, the quantity of DNA was too low to use the new technologies now available. She mentioned that these results did not invalidate the old ones which had established a male genetic profile.

At the end of the morning, Marc-André Grenon's lawyers asked the judge to grant them a weekend of reflection to determine whether or not they will present a defense. They should announce their decision when the hearings resume Monday morning at the Chicoutimi courthouse.

Loading in progressToronto receives 143 million from the federal government for asylum seekers

Toronto receives 143& nbsp;million from the federal government for asylum seekers

ELSELL ON INFO: Toronto receives 143 million from the federal government for asylum seekers

Judge François Huot told the jury that there were two possible options: either there will be a defense, or no additional witnesses will be heard.

The trial of Marc-André Grenon began on January 15. Since then, Crown prosecutors have called 11 witnesses: Guylaine Potvin's friends who discovered her body, an ambulance driver, a crime scene technician, a forensic pathologist, the victim's roommates, police officers from the Sûreté du Quebec and specialists in forensic biology.

The murder of Guylaine Potvin was committed on the night of April 27 to 28, 2000.

Male DNA was found on objects left at the crime scene, as well as on the victim's body. However, to determine who the DNA comes from, one must be able to compare it, which has proven impossible in this case for more than two decades.

Open in full screen mode

One glass and two straws used by Marc-André Grenon were recovered from the trash can of a cinema.

It was only 22 years after the murder that the alleged murderer was arrested in Granby.

< p class="StyledBodyHtmlParagraph-sc-48221190-4 hnvfyV">In order to relaunch the investigation, Guylaine Potvin's file was added to the PatronYme project. As part of this project, the Montreal Laboratory of Judicial Science and Legal Medicine created the pYste database. The latter contains thousands of public genetic profiles from online genealogy sites.

Male DNA contains a Y chromosome. This is transmitted from father to son, so that the Y profile of men from the same paternal line is the same. Traditionally, the father's family name is also passed down from one generation to the next.

The unknown DNA in Guylaine Potvin's file was therefore compared to the data contained in pYste. The Grenon surname has been targeted as a surname of priority interest. This is what allowed Sûreté du Québec investigators to relaunch the investigation and find Marc-André Grenon, whose name had appeared in police files a long time ago.

In August 2022, investigators obtained the right to follow Mr. Grenon and they seized, without his knowledge, a cup and straws that he had used in a cinema in Granby. By comparing his DNA and that found in Guylaine Potvin's room, there was a match.

The police thus obtained a warrant and they arrested Marc-André Grenon at his workplace on October 12, 2022.

• Mireille Chayer (View profile)Mireille ChayerFollow