A forensic pathologist has told a Winnipeg murder trial that he could not determine what killed a 15-year-old girl whose body was found in the Red River.
Raymond Cormier has pleaded not guilty to second-degree murder in the 2014 death of Tina Fontaine.
The Crown told the court Cormier killed the girl because he had developed a sexual interest in her and found out she was underage.
Fontaine was killed in August 2014 after she ran away from a hotel where she was being housed by Manitoba Child and Family Services.
Dr. Dennis Rhee testified that his forensic examinations found no definitive injuries on the outside of her body or to her internal organs.
He says there was no evidence of a sexual assault, no signs of a stabbing or major blunt force trauma.
"The cause of death still remains undetermined," he told the jury trial Wednesday.
He said suicide would be unlikely because Fontaine's body was wrapped in a duvet and weighed down with rocks.
Rhee suggested that could indicate someone may have been trying to conceal the body.
"The way the body was presented is highly suspicious," Rhee testified. "I would not be able to rule out a minor assault."
He said he couldn't rule out a drowning, but there is no evidence that she drowned.
Rhee estimated Fontaine's body was in the Red River between three to seven days.
In earlier testimony, Christopher Keddy, who works at the RCMP national forensics lab, told court that Fontaine had enough alcohol and traces of marijuana in her system to make her high.
Keddy testified the toxicology results showed no clear sign of harder drugs.
During cross-examination, defence lawyer Andrew Synyshyn suggested to Keddy that he could not rule out the possibility that Fontaine could have had a potentially lethal combination of drugs in her system.