09/20/2017 12:55 EDT | Updated 09/20/2017 13:02 EDT

Calgary man who strangled wife, buried body in home gets 7 years in jail

CALGARY — A Calgary man who strangled his wife and disposed of her body after enduring what he described as years of domestic abuse has been sentenced to seven years in prison.

Allan Shyback will get credit for time already served so he faces just under three more years behind bars.

Justice Rosemary Nation found Shyback guilty last spring of manslaughter and indignity to a body in the 2012 death of Lisa Mitchell in the couple's Calgary home.

Shyback, 40, testified that he killed Mitchell while he was defending himself as she attacked him with a knife, and that he panicked and buried her body in the basement.

Nation said Wednesday that covering up the crime was cold and calculated, especially since the victim was the mother of young children. But she also found that his moral culpability was medium to low since there was no evidence of brutality and no weapon was used.

Nation suggested Shyback can still become a contributing member of society.

"Nothing will bring Lisa Mitchell back to life," she said, adding Shyback appears remorseful and pleaded guilty before the trial.

Before Nation handed down her sentence, Shyback told court that "fear overwhelmed his sense of right" and that he is ashamed of what he did.

"The loss of her has impacted so many lives and she will be greatly missed. I deeply regret the offence that led to this. I have regret and am shamed at my actions that followed," Shyback said.

"I let fear overwhelm my sense of right and responsibility, and that is not an example that I would have wanted to set for my children. All I can do now is express how deeply sorry I am for what has happened and accept responsibility."

During his trial, Shyback testified that he had been the victim of domestic abuse for nearly a decade and that Mitchell had attacked him with a knife the day she was killed.

An undercover police operation started in 2013 and ended with Shyback's confession and arrest in Winnipeg.

Shyback was also found guilty of causing an indignity to a body for putting Mitchell's remains in a Rubbermaid container and cementing it into a wall in their basement.

Shyback's lawyer Balfour Der argued his client should serve five years total — three years for manslaughter and an additional two for indignity to a body, which he called "a minor offence in the Criminal Code." He said Shyback's moral culpability was low.

"Mr. Shyback didn't start this fight," said Der. "It came down to a very quick event and death followed."

Crown prosecutor Jayme Williams recommended Shyback serve 10 years for manslaughter and an additional three to five years for concealing her body in the home they shared with their children.

"For a whole year they believed that their mother was either in hospital or had left them while they were living in the home where her body was entombed," Williams said.

"There is most certainly going to be a psychological impact when the children ultimately become aware of the fact they resided in the home with their mother's body entombed in the basement."

Peggy Mitchell, the victim's mother, said her grandchildren have lost both of their parents.

"They think mom is in heaven and dad is with police," she said.

The victim's sister-in-law said she wanted Lisa Mitchell to be a bridesmaid at her wedding but never got the opportunity because she was "stolen" from the family.

"It was your fault," Sarah Mitchell said to Shyback. "Every time I look at you I want to throw up."

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