CALGARY â€” The Crown says a man accused of killing his wife confessed to undercover officers that he strangled her and buried her body in the basement of the home they shared with their two children.
The trial of Allan Shyback, who is charged with second-degree murder and causing an indignity to a body, began Tuesday. He is accused of killing Lisa Mitchell, 31, who was last seen walking from her house to a convenience store in October 2012.
An undercover operation police launched in 2013 ended with Shyback's arrest in Winnipeg a year later.
"It ended on Dec. 5, 2014, with the accused confessing to have killed Lisa Mitchell by strangling her to death," prosecutor Heather Morris said in her opening statement.
"The accused took significant steps to cover up the death and cover up his role in the death. At the end of the day, the Crown will prove the accused intended to cause the death of Lisa Mitchell."
Mitchell's mother told the judge hearing the case that her daughter and Shyback had a "volatile" on-again, off-again relationship.
Peggy Mitchell said she usually talked to her daughter two or three times a week and last saw her Oct. 28, 2012. She became worried when Lisa didn't show up for a shift at a bar in Longview, Alta., the following weekend.
Mitchell testified that Shyback told her he had gone to the store and, when he returned 20 minutes later, his wife was gone.
The mother received an email that same day saying her daughter had met someone and had to get away.
"It seemed to make sense but it wasn't her. It wasn't personal. It wasn't the way she spoke."
Mitchell was also suspicious over a voice mail on her phone at 2:45 a.m. on Nov. 15, 2012.
"Hey, I'm OK," a woman's voice said on the tape. "Sometimes my weeks get crazy, you know, and it was quiet for a while, and then all of a sudden this happened and, within a half a day, I should, but he's back now and I gotta go. Love you," the voicemail continued.
"She wouldn't have called me at that time. She would have called me when we maybe could have spoken," Mitchell said.
"It was just like her words ... (but) it was totally, totally off."
Shyback admitted in an agreed statement of facts filed with the court to using previously collected recordings of his wife's voice to create the message left on Peggy Mitchell's phone.
Court heard a search of the crime scene that included the home's computer revealed an Internet history on how body decomposition is affected by salt, lye, concrete, lack of air and lack of insect activity.
Alberta's assistant medical examiner at the time said Mitchell's body was brought into the autopsy room in two plastic tubs and appeared to be encased in white pellets.
"I believe it was a mixture of cat litter ... mixed in with salt tablets," said Dr. Jeffery Gofton.
The cause of death appeared to be a fractured thyroid cartilage, he said.
"The body was diffusely discoloured in a brown appearance. I believe it was that of mummification which typically has more of a leathery appearance or leathery texture."
Police Const. Karl Sudyk described the eventual recovery of the body from the basement.
He said a number of containers were packed on top of a fresh cement structure.
"It (the cement) was removed with brute force ... sledgehammers, picks, air chisel, hammers," said Sudyk.
Police found a blue plastic container sitting on a blanket with Mitchell's body inside.
Sudyk said cat litter, bleach, detergent, air freshener and a water conditioning soap were found.
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Bill Graveland, The Canadian Press