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Michael Rafferty's lawyer grilled his client's former girlfriend Thursday, suggesting Terri-Lynne McClintic was the "engine" behind the abduction and murder of eight-year-old Victoria Stafford – a charge McClintic flatly denied.

In a tense exchange inside a London, Ont., courtroom, Rafferty's lawyer Dirk Derstine pressed McClintic to "tell us that you did more than just kill her."

"In fact, I'm going to suggest to you that you were the engine who drove the events of that day," Derstine said.

"That will never happen because that's not the truth," McClintic said.

McClintic, 21, is the star witness at the trial of her ex-boyfriend Rafferty, 31, who has pleaded not guilty to kidnapping, sexually assaulting and murdering the Grade 3 student everyone called Tori.

The little girl was abducted as she walked home from her Woodstock, Ont., school on April 8, 2009. Her body was discovered in a rural area 103 days later.

McClintic pleaded guilty to Tori's murder in 2010 and is currently serving a life sentence in prison.

She has provided conflicting testimonies to police and on the stand, first telling an OPP investigator it was Rafferty who killed Tori by striking her head with a hammer, then testifying in court that she was the one who delivered the fatal blows.

A videotape of a police interview with McClintic four days after Tori went missing was played in court Thursday.

McClintic, then still a teenager, was shown surveillance video of a woman in a white puffy coat walking with Tori near her school.

In the police video, McClintic laughs and says there's "no way in hell" that was her.

In a subsequent police interrogation, which was entered into evidence on Wednesday, McClintic admits to OPP investigator Jim Smyth that she took the girl and says Rafferty killed her with a hammer.

In court Thursday, McClintic said she was initially unable to accept the fact that she had killed a child, so she genuinely believed she was not the woman on that surveillance tape.

"I had pushed things out of my mind," she testified. "I just couldn't believe that I was involved with something like this. I'm not denying that I have a history of violence, but I'm not violent towards children and I've never hurt a child in my life."

Earlier Thursday, Derstine questioned McClintic again about disturbing letters describing violence and torture she had written in a youth prison one year before Tori's death.

McClintic told Derstine the violent images in the letters were her way of venting anger.

"Are you telling me you're not a violent person?" Derstine demanded of McClintic, who then responded that she had "anger issues."

"You confessed under oath to beating a child to death with a hammer. Anger issues?" Derstine asked bluntly.

McClintic appeared to be crying during Thursday's testimony, not sobbing but sniffling.

Derstine, reviewing McClintic's criminal record, also showed her pictures of her mother with a black eye that she received during a scuffle between the two.

McClintic replied that she takes "full responsibility" for her actions.

"I'm not saying it was OK to hit her," McClintic said about her mother. "Regardless of the things that happened with my mother, I do love her very much and I'm very sorry," she testified while crying.

McClintic's mother lost 70 per cent of the vision in the injured eye in the altercation, court heard.

With files from The Canadian Press