Guy Turcotte's lawyer wants the Supreme Court of Canada to consider overturning a Quebec Court of Appeal ruling ordering a new trial after Turcotte was found not criminally responsible for killing his two children in 2009.
Defence lawyer Pierre Poupart announced Friday he would make the request to the country's top court.
Turcotte was due back at the St-Jérôme, Que., courthouse Friday to learn the start date of his new trial on two counts of first-degree murder.
The Quebec Court of Appeal ordered a new trial in November after overturning the 2011 decision that Turcotte was not criminally responsible for the stabbing deaths of his children due to a mental disorder.
The former cardiologist admitted to killing Olivier, 5, and Anne-Sophie, 3, at his rented home north of Montreal.
During his first trial, Poupart argued that his client was suffering from mental difficulties stemming from his troubled marriage to Isabelle Gaston, the mother of the children, and that he was not aware of what he was doing.
The Crown argued that the slayings were premeditated. The children died in Turcotte's home – a month after he and Gaston split – during a weekend he was caring for them.
Turcotte was detained at Montreal's Pinel Institute, a psychiatric hospital, until his release in December 2012.
New trial on murder charges
Turcotte turned himself in to police the night of Nov. 13, 2013, the same day that a Quebec Court of Appeal judge ruled to overturn his 2011 verdict. He was formally charged the next day with two counts of first-degree murder.
Gaston, Turcotte’s ex-wife, was shocked by the 2011 verdict. She said at the time that she didn’t want an appeal and that she would never appear in court again in the case.
Later, after Turcotte was released with conditions after 46 months at the Pinel Institute, Gaston spoke out.
"As a victim I had to scream that there was an injustice. I thought that there were terrible errors that happened in [that] courtroom," she said.
Gaston later had a change of heart and said she welcomed the appeal of her ex-husband's verdict. She said Turcotte deserved to be in prison for killing their children.
"I try to be here now, in the present," she said. "When I wake up in the morning I don't feel that I have the right to let my children down, I don't feel that I can let go of this responsibility even if they died … We cannot kill someone and be free."