The Crown is proceeding summarily, meaning Terri-Lynne McClintic, who made a brief video appearance, will stand trial in Ontario court of justice, her lawyer Geoff Snow said.
"She has rights and she's exercising them," Snow said from London, Ont.
The hearing Sept. 12 is expected to last about six hours.
The charge stems from an incident Jan. 30 at the Grand Valley Institution for Women in Kitchener, Ont., where McClintic is serving her sentence after pleading guilty two years ago to Tori's first-degree murder and kidnapping.
The Crown alleges McClintic got into a fight with another inmate, who is also serving a life sentence for first-degree murder for instructing two men to kill her former lover.
During her recent testimony against Michael Rafferty in London, Ont., who is on trial for Tori's first-degree murder and kidnapping, McClintic, 21, admitted to attacking a fellow inmate.
"Yes, I did assault her," McClintic said in response to prodding by Rafferty's lawyer, Dirk Derstine.
"I confronted her about some things and things escalated."
Court heard that McClintic had asked to see the inmate for peer support but got into a brawl where she kicked and stomped the other woman, who was curled up in the fetal position.
Snow said McClintic would not admit to the assault charge when she appears in court.
"She'll be arraigned on the trial date and she'll enter a plea of not guilty," Snow said.
Her testimony from the Rafferty trial cannot be used against her at the assault trial because she was compelled to give evidence at the hearing, Snow said.
Rafferty, 31, has pleaded not guilty to first-degree murder, sexual assault causing bodily harm and kidnapping. His trial is in its final stages, with closing arguments and the judge's charge to the jury still to come.
It's alleged that Rafferty and McClintic, who was then his girlfriend, kidnapped Tori outside her school in Woodstock, Ont., on April 8, 2009.
The Crown alleges Rafferty raped the girl in a secluded field.
McClintic, who pleaded guilty two years ago to first-degree murder, had previously said Rafferty killed Tori, but in her recent evidence said she wielded the hammer.
McClintic has testified that she kicked Tori, who was in the fetal position, before the Grade 3 student was killed with hammer blows to the head.
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