Revenge and a case of mistaken identity were key factors in the death of a University of Calgary student, according to the prosecution's opening statement at the trial of a young offender.

The young woman on trial Monday in a Calgary courtroom for first-degree murder can’t be named under the Youth Criminal Justice Act because she was 17 at the time of the crime.

Brett Wiese was a 20-year-old business student in January of 2013 when he was stabbed and bled to death while waiting for a taxi after a friends' party on Brisebois Drive in northwest Calgary.


Brett Wiese was waiting for a cab after a party. (Courtesy of the Wiese family)

In its opening statement, prosecutor Carla MacPhail outlined the Crown's theory that two and a half hours earlier, a group of young women, including the accused, arrived uninvited to the house party. After being asked to leave, the accused became enraged and got in a fight with Brett Butler, one of the men who lived in the home.

The fight turned physical on the front lawn. MacPhail says the girl refused to leave, demanding to know Butler's name and threatening to have him killed.

Eventually police arrived, broke up the fight and sent the group of girls on their way.

Unwanted guests

For the next two and a half hours, the girl is accused of making calls, sending texts and gathering a group of friends.

McPhail says about 10 people returned at around 3 a.m. and burst into the home looking for the "Brett" who had kicked the accused and her friends out of the party. Instead, they are said to have found Brett Wiese in a bedroom of the house, waiting with a friend for a taxi.

Mitchell Harkes, who was with the returning group, is accused of stabbing Wiese six times. Wiese began screaming and examining his injuries when the young woman on trial is accused of stabbing him once more in the back.

Wiese bled to death, losing almost half his blood.

"The Crown's theory is that [the girl] is criminally liable for all of the violence that occurred in that home when the group burst in. She planned and deliberated an armed intrusion ... with murderous intent."

The young woman also faces three assault charges for injuries sustained by other party-goers.

Her co-accused, Harkes, faces a second-degree murder charge. His trial is set for Sept. 8.

Though she is protected under the Youth Criminal Justice Act, the Crown has applied to have the girl sentenced as an adult if convicted.

That would mean she could face a life sentence with no chance of parole for at least 10 years.