Matthew de Grood's defence is expected to argue he was not criminally responsible for the 2014 slayings.
As the trial for Calgary's worst ever mass killing began this week, defendant Matthew de Grood, 24, through an agreed statement of facts, admitted he stabbed the five victims to death. He didn't enjoy it, but said "the son of God was controlling me."
De Grood has pleaded not guilty to first-degree murder charges in the deaths of Lawrence Hong, 27, Joshua Hunter, 23, Jordan Segura, 22, Kaitlin Perras, 23, and Zackariah Rathwell, 21. The first three were students at the University of Calgary while Perras went to Mount Royal University and Rathwell attended the Alberta College of Art and Design. They were killed early on April 15, 2014, at a house party celebrating the end of the school year.
The defence is expected to argue de Grood is not criminally responsible for the crimes.
In court Monday, Crown prosecutor Neil Wiberg read aloud the statement of facts, which included de Grood's interviews with police officers, the Canadian Press reports. It reveals that, de Grood, a U of C student and son of a veteran Calgary police officer, told cops "what I did may seem atrocious but I was killing Medusas, werewolves."
He also said he tried to be merciful when committing the stabbings.
"I aimed for their heart. They put up a struggle which made it hard, but, so you know, it wasn't sadistic or anything."
De Grood was working a shift at Safeway on the night of the stabbings. His friend Daniel Butler, quoted in the statement of facts, said he invited de Grood to the party, located in the city's Brentwood neighbourhood. De Grood acted strangely, telling Butler he believed the apocalypse was coming at midnight.
Later, according to the agreed facts, he smashed his cell phone with an axe after dropping it into a fire.
De Grood said he grabbed a 21-centimetre blade chef's knife from inside the kitchen with which he attacked Rathwell; they'd had an argument about Buddhism.
"Then the people on the couch saw and obviously started freaking out, so I killed them from left to right as quickly as I could," he told police. "The girl ran into the corner so I went and stabbed her. I said 'I'm sorry I have to do this.' Then the guy from the kitchen wasn't dead. I had to hunt him down. Then I just left."
Witnesses approaching the house after 1 AM saw de Grood chasing Hunter outside; Hunter then collapsed on the ground. De Grood, his hands covered in blood, threw his knife on the ground and ran off. Segura, Rathwell and Hong were dead inside the home while Perras was fatally injured.
When cops caught up with de Grood, they found cloves of garlic on him, which he said were to "keep the zombies away." That same night, he also said he was an alien, according to the CBC.
De Grood's father, Calgary police inspector Doug de Grood, had reportedly been concerned about his son's mental health leading up the killings, as was at least one of his friends. The court heard that de Grood had been posting Facebook updates that referred to killing vampires and incarnation.
As the proceedings started, Gregg Perras, father of one of the victims, read a statement to reporters.
"It is immeasurable to comprehend the anguish and sorrow we have experienced over the last two years," he said. "Only those who have experienced significant loss can relate."
The trial continues Tuesday.
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