Betty Anne Gagnon was found dead in a pickup truck outside a rural convenience store near Sherwood Park, Alta., in November 2009.
She had bruises on her face and weighed just 65 pounds. She had been living in a converted school bus with no heat, running water or electricity.
Her sister, Denise Scriven, and Scriven's husband, Michael, faced multiple charges, including manslaughter and unlawful confinement, but pleaded guilty Friday to failing to provide the necessities of life.
They are to be sentenced April 19.
Gagnon, who was 48, required constant care and was sometimes confined in a chicken coop and a dog run, court head.
Denise Scriven said in an agreed statement of facts that she and her husband would lock Gagnon in the garage, bus and basement. She said she took her sister's boots so she couldn't venture off.
The statement said Michael Scriven told RCMP he had kicked Gagnon out of the house because he was angry with her for smearing her feces around.
He said he built several places for her to live outside the house. He described one as a jail cell in the garage, but earlier court documents said it was a pen made out of chicken wire and blankets.
There were references to using a kitchen cleanser on Gagnon and spanking her up to 75 times.
It was also revealed that the couple admitted to police they were crack cocaine users and that on the day Gagnon died, her sister had gone to get some of the drug.
Police seized a video the Scrivens took of Gagnon attempting to get out of her makeshift cell and being abused as punishment.
Gagnon's three former caregivers leaned over, sobbing and rubbing each other's backs, as the statement of facts was read in court.
"I don't think we'd ever treat an animal that way," said Sue Thomas. "She was nothing. It was like she wasn't even a person. They treated her like she wasn't even a human being."
"Shocked, I think, would be the first word that I would use," added Suzanne Jackett. "What we heard was so disturbing and very, very difficult for us to hear ... (what) happened to our friend Betty Ann and the circumstances under which she lived in the last days and months of her life."
Despite what they heard, the one-time caregivers said having the details made public gives them some peace.
"If that had not come out to the degree that it did, we wouldn't have any satisfaction at all, because we would have felt that the Scrivens had gotten away with a whole bunch of stuff that the public didn't know about," said Jackett.
"By them standing up and admitting to those facts, they've admitted, they've agreed that this is what they did.
"We needed to hear that."
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