Parsons took her own life earlier this year when she was 17 years old. Her family alleges she was sexually assaulted by several boys at a party and a photo of the incident was circulated online. Her family said she was bullied for months, and the relentless taunting led to her death.
She was first admitted to the IWK Health Centre several months after the alleged assault.
Glen Canning said that in March 2012, his daughter was suicidal, and he took her to the emergency department. She was admitted to 4-South, the mental health unit.
The environment with other suicidal and depressed teens actually made things worse, he said.
"She learned how to cut in there," Canning said. "She was never cutting herself before."
At one point, Canning said, hospital workers suspected his daughter was hiding a razor.
"They searched her whole room, couldn't find anything. She was getting mad at them."
He said that's when two men took Parsons into a side room and strip-searched the teen.
"Their justification was that she was abusive, she was being violent, she was out of control."
But Canning said there's no justification to treat a teenage girl in that way.
"They held her down and they took her clothes off," he said. "This is a rape victim, who is traumatized and suffering from depression."
Canning said no razor was found.
He acknowledged that the program did help his daughter in some ways and provided a shelter from her bullies. She spent time working out in the gym and worked with horses at a nearby stable.
But after the search, he said, the damage was done. The family debated what to do, and in the end, Parsons left the hospital.
"It did the exact opposite of what I thought it would do. I know there's good people there, beautiful, wonderful people there."
The IWK Health Centre couldn't comment on Parson's specific treatment for privacy reasons.
In an email to CBC News, the health centre confirmed that in extreme circumstances, clothing is removed from patients who are at a severely high risk of using their clothing to harm themselves.
"They are placed in the Time Away Room and are visually monitored 24/7 by RN/LPN [registered nurse/licensed practical nurse]," wrote Karen Butt, the public relations co-ordinator. She said safety blankets are provided to the patients.
She added that the hospital tries to have staff who are the same sex as the patient remove a patient's clothing, but that's not always possible.
"Patient safety is our main concern," she said.
Canning wants the IWK to acknowledge its treatment of his daughter was wrong.
"This just made it even more worse, because now her trust has been violated, and her belief in them helping her has been completely shattered, and I'm thinking 'You've gotta get out of here,' and I think Rehtaeh was heartbroken, really."
Friday marked two months since Parsons was taken off life-support. As a tribute, people around the world started a digital campaign called Hands Up for Rehtaeh. Dozens shared photos online of her name written on their wrists.
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