Nina Courtepatte's body was found on a golf course on Edmonton's outskirts two years ago. ((CBC))

A young woman charged in the murder of Nina Courtepatte didn't know her companions planned to rape and kill the 13-year-old and may have thought she was helping a friend find a date, her lawyer argued Tuesday.

Nobody, not even the then 17-year-old accused,took Joseph Laboucan seriously when he told several young people as they were driving around that he wanted to kill someone, Colleen Connolly told an Edmonton courtroom during her closing argument.

The lawyer said Laboucan and his friends said a lot of things in a "farcical conversation" the night before Nina was lured from West Edmonton Mall with the promise of a party, then was savagely raped and beaten on a golf course just west of Edmonton.

The group talked about cutting people's heads off and throwing them out onto the street. Laboucan, convicted last month of Nina's murder, said he was looking for sex.

Nobody, including the accused,took the chatter seriously, Connolly suggested.

"Given the atmosphere of the vehicle, the response of the parties to it, when it was said – it has to be considered."

Connolly said the accused, who's now 19 but can't be namedbecause she was17 at the time of the murder, may have thought she was setting Laboucan up with a date when she helped get Nina into the car the next night.

"What eventually happened to Nina does not make [the accused] morally culpable for her innocent attempt to help her friend find a female companion," Connolly said.

In a crime that horrified Edmonton and drew national headlines, Nina and a friend were taken to a muddy fourth-hole fairway where the teen was raped twice and bludgeoned to death by a group of self-described "mall rats."

One youth has already pleaded guilty to first-degree murder in the April 2005 slaying, while Laboucan of Fort St. John, B.C., was sentenced to life in prison for his role. A second man, Michael Briscoe of Edmonton, told police he was simply swept along in the events and was acquitted.

Laboucan is appealing his conviction, while the Crown is appealing Briscoe's acquittal.

A third trial of another underage female is scheduled for later this spring.