Martin Tremblay was convicted of criminal negligence causing the deaths of 17-year-old Martha Jackson and 16-year-old Kayla Lalonde, who died in March 2010 after partying at Tremblay's home.
Tremblay's trial heard he invited the two girls and their friend to his home in Richmond, south of Vancouver, where he gave them alcohol and drugs and then videotaped himself fondling them once they passed out.
When the girls' conditions deteriorated, he failed to help them. He drove Lalonde to nearby Burnaby and left her on the ground, and only after he left did an associate of his call for help. The following morning, when Jackson stopped breathing, he attempted to persuade another person in the house not to call 911.
Crown counsel Michaela Donnelly says Tremblay, a convicted sex offender, poses a serious risk to the public.
"He has a distinctive and repetitive pattern of behaviour," Donnelly said in court Monday on the first day of a dangerous offender hearing.
"He targets young, vulnerable teenage girls, almost exclusively those of First Nation descent. ... They're often heavy users of alcohol and drugs. He grooms them, he knows that they are vulnerable, he facilitates and encourages self-destructive behaviour."
Donnelly said Tremblay fits the criteria to be labelled a dangerous offender and should receive an indeterminate sentence.
Tremblay was convicted in 2003 of assaulting five aboriginal girls who were between the ages of 13 and 15. He invited them to his house to party, gave them alcohol and drugs, waited until they passed out and videotaped himself sexually assaulting them.
He is currently awaiting trial on separate charges related to four other girls, though it's not clear whether evidence related to those allegations, which haven't been proven, will be admitted into the dangerous offender hearing.
Donnelly said Tremblay displayed little interest in rehabilitative programming during his previous time in custody and his prospects for treatment are low.
"Mr. Tremblay is going to continue to be dangerous in the future," said Donnelly. "There will be great risk to the public."
Outside court, Eliza Willier, who is Lalonde's aunt and raised the girl throughout much of her childhood, said she hopes Tremblay is never released.
"Sure, he's behind bars, but that doesn't give us any comfort," she said.
"He could have helped those girls and he chose not to — and he's done this before."
Willier said the death of her niece, who she described as "full of life," has left a painful hole in her family.
"It's a big loss to us. She's not here anymore. She's a big part of our family and we miss her a lot."
The outcome of the dangerous offender proceedings will be affected by an ongoing court challenge in another case.
A B.C. Supreme Court judge issued a ruling last November that concluded the current dangerous offender regime, which was overhauled in 2008, violates the charter.
At issue is whether a judge can consider the potential for treatment when deciding whether to declare someone a dangerous offender.
Currently, such a designation is mandatory if a judge concludes that an offender meets certain criteria, and potential treatment can only be considered at the sentencing phase.
The judge concluded the law violates the provision of the charter that deals with liberty and security of the person, but he stopped short of declaring the law unconstitutional.
A hearing is scheduled in February to determine whether the law should be struck down or whether it can still be upheld as reasonable.
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