09/20/2017 13:58 EDT | Updated 09/20/2017 14:22 EDT

'Deeply sorry:' Calgary man who strangled wife, buried body in home gets 7 years

CALGARY — A man who strangled his wife and concealed 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. He said he panicked, put her body inside a plastic bin and cemented it into a basement wall.

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

Shyback has expressed remorse and Nation said she believes he can still become a contributing member of society. His experience, including his imprisonment, will likely deter him from future criminal involvement, she said.

"I hope that you would use your remaining time in prison wisely," Nation said Wednesday. "You can return to being a contributing member of society but that future is in your hands."

Before he was sentenced, Shyback told court that "fear overwhelmed his sense of right." 

"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.

"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."

Outside court, defence lawyer Balfour Der said his client was relieved and hopes to eventually reconnect with his children. Der estimated Shyback could be out of jail in as little as seven months.

"He's extremely remorseful about this and has been all along," Der said. "He's relieved now that it's over and he's relieved that it ended up being manslaughter and not murder."

Mitchell's mother, Peggy Mitchell, said she is satisfied with the sentence although she had hoped it would be a little harsher. She said her grandchildren are living with her and are doing fine, but don't know all the details of their mother's death.

"They understand their dad is with the police and their mom's an angel," she said.

Mitchell said the family has kept "printed stuff" of what happened and it will be up to the children to decide, once they're older, it they want to see it.

Mitchell was last seen in 2012. An undercover police operation started in 2013 and ended with Shyback's confession and arrest in Winnipeg.

Crown prosecutor Jayme Williams had called for a sentence of 13 to 15 years. He said an aggravating factor was that the couple's children were living in the home where their mother was buried.

"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."

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