Guy Turcotte cries on the stand at 1st-degree murder trial

Guy Turcotte broke down in tears on Tuesday as he testified at his murder trial about hugging his children just hours before they were stabbed to death.

On Feb. 20, 2009, Turcotte found out in a telephone conversation with Isabelle Gaston, his estranged wife at the time, that she had changed the locks on the home she had kept after their separation.

"It was like the last thing she could take from me and she took it," said Turcotte, who is charged with two counts of first-degree murder in the deaths of Olivier, 5, and Anne-Sophie, 3. "I couldn't believe it."

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​Turcotte testified that, in a moment of frustration, he told Gaston: "You want a war, you'll get one."

He said he was referring to the fact she had just told him in the same conversation she had consulted a lawyer.

That afternoon, he picked up Olivier and Anne-Sophie, went to the video club to rent movies and buy chips and then made spaghetti supper as the children watched a video.

"I'm feeling sad," he told the court in the present tense. "I sit in the living room with them and the tears just flow, in silence...I cry."

Olivier must have noticed, he testified. "He comes over, gives me a hug and takes me in his arms...Anne-Sophie does the same thing," he said, sobbing.

That's when his testimony was suspended.

While Turcotte, 43, has pleaded not guilty to the two murder charges, he has admitted to causing the children's deaths.

Turcotte began his testimony on Monday, shortly after one of his lawyers, Pierre Poupart, told the trial he will argue that his client should be found not criminally responsible in the slayings.

The accused also testified at length Tuesday about his almost daily squabbles with Gaston in January and February 2009.

One in particular occurred at the beginning of February when he learned the children had gone to Quebec City for the winter carnival with Gaston and her new beau, Martin Huot.

"A sledgehammer to the forehead wouldn't have hurt as much," he said, referring to the moment when Olivier told him on the phone about the Quebec City getaway.

"Then I realize I am absent, that I am no longer there. That Martin is taking my place.

"I hang up and I start bawling, I'm bawling...I'm losing my place in my kids' family life. I can't believe it. I am shattered."

On Monday, Poupart said that while the Crown must prove beyond a reasonable doubt that Turcotte was responsible for the crime, the burden of proof required to establish a defence of not criminally responsible by way of mental problems is not as great.

He also reminded the jurors they will need to reach a verdict based on the evidence and not on their emotions.