Douglas de Grood, a veteran city police officer, stood with his wife in front of reporters Thursday and said the family is devastated and is trying to make sense of the tragedy.
He described his son, Matthew de Grood, as a great kid who respected others, had good grades and played sports. As a young man, he attended university and raised money for charities through his passion for running.
The 22-year-old had a bright future ahead of him, said his father, and had been accepted into law school for the fall.
"Just like you, we struggle to understand what happened," said the senior de Grood, choking back a sob.
He was shaking visibly as he delivered his statement. He leaned on a cane for support and, at one point, paused in an effort to gain control.
His son's defence lawyer, Allay Fay, explained that the officer has mobility issues but would not say whether he has a medical condition.
The father said his family has received support from many people, including strangers.
"We will never recover from this, but the collective support has helped ease some of the pain. We hope someday we will have answers as to why this happened. Regardless, it won't bring the victims back, but we would give anything to do just that."
Matthew de Grood faces five counts of first-degree murder in what police are calling the worst mass murder in Calgary's history.
Police have said de Grood finished his late shift at a grocery store before going to a house party which was being held to celebrate the last day of classes at the University of Calgary. He was an invited guest and mingled with some of the 20 people there before he allegedly grabbed a large knife and started attacking people one by one.
Police said a significant part of their investigation will focus on whether de Grood was suffering from mental illness and officers will be looking into any communications he had with people before the slayings.
The Calgary Herald reported that de Grood sent disjointed and confusing text messages to his family before showing up at the party. The newspaper quoted an unnamed officer close to de Grood's father as saying the family was worried he might commit suicide that night. His mother called police and his father went looking for him, the source said. The story also said de Grood had mental health problems in high school.
Fay said he knows nothing of any texts and had not heard that his client had been mentally unstable in the past. He said de Grood's family doesn't agree with a lot of things being reported in the news media, but did not elaborate.
De Grood remains in custody at a psychiatric centre. Fay had earlier indicated a psychiatric assessment had been ordered, but clarified Thursday that that order had yet to be given. He said he expected the Crown would request one when de Grood appears in court Tuesday.
Fay said he has met with de Grood, but the man's parents have yet to see their son.
"He appeared distraught. He appeared upset. He appeared fearful. All those things that one would expect under those circumstances," Fay said of his client.
Police spokesman Kevin Brookwell said any messages de Grood sent before the party would form "a significant part of this investigation." He told reporters that if any texts exist, they might help explain the suspect's state of mind and also provide clues to a motive.
Investigators have said it appears there was nothing — no grudge or vendetta — that might have provoked the attack. They aren't even sure de Grood knew the victims.
Brookwell said officers are still interviewing witnesses and piecing together what happened at the party. He said it's not known how one person managed to kill five people in a crowded home and escape. De Grood was taken into custody about 40 minutes after the attack, with the help of a police dog.
"There's going to be a lot of guessing and everybody's trying to get that answer as to how this possibly could have happened and did no one intervene?" said Brookwell. "It is quite possible that people didn't even know it was going on, people froze."
The victims have been identified as Zackariah Rathwell, 21, Jordan Segura, 22, Josh Hunter, 23, Kaitlin Perras, 23, and Lawrence Hong, 27.
Two Edmonton prosecutors have been assigned to the case to address any perception of bias because of de Grood's father. Brookwell dismissed any notion that an outside police force should also be brought in.
He said police made a speedy arrest and charges had been laid by the end of the day.
The City of Calgary has lowered all flags at its municipal buildings and said they will remain at half-mast until sunset on the day of the last victim's funeral.
The first service has been set for Segura on Monday.
Note to readers: This is a corrected story. An earlier version attributed the police comments to Acting Insp. Ryan Ayliffe
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