Dr. Greg Passey said he received a call the evening of Sept. 10, 2012, from an officer who said Matters was inside a cabin and threatening to shoot members of the emergency response team who had formed a perimeter outside.
The officers were there to arrest Matters for assaulting his brother during an altercation about 40 hours prior.
"I said something to the effect that you don't want him backed into a corner where he does not feel he has any options. If you push him into that situation, he will defend himself. I was fairly certain of that," Passey testified.
They discussed potential strategies to defuse the situation unfolding on the property where Matters lived with his mother near Prince George, B.C.
"All the while I was expecting to be able to talk to him."
That didn't happen.
The officer ended the call, suggesting that a surrender had been negotiated. He heard nothing until the next day, when he saw on the news that Matters, 40, a 15-year soldier who had served as a peacekeeper in Bosnia, had been fatally shot by RCMP.
"It is my true opinion and conviction that had I been able to speak to Greg that night, I could have talked him out," Passey said.
Several family members fled the inquest room in tears as a forensic pathologist demonstrated where two bullets entered Matters's back, exiting through his chest. A third bullet remained in his body, jurors were told.
Passey, the head of the B.C. Operational Stress Injury Clinic in Vancouver, which treats soldiers and police, past and present, explained how Matters developed PTSD.
He was assaulted twice by members of his unit in 1995, Passey said. Matters filed a complaint but he was the one charged, and he believed that was because another soldier involved in the beating was of a higher rank.
Later, he had several run-ins with RCMP, in New Brunswick where he was based and later in Prince George. On one occasion, officers from the Prince George detachment came into his home at gunpoint, at night, to do a "wellness check."
"He never felt he was being heard. He never felt he was getting justice," Passey said, explaining why police, and a sense of injustice, would trigger Matters's PTSD.
His verbal threats — against an estranged brother, police, the police complaint commissioner, a former therapist — were "primitive and immature" responses, the psychiatrist said.
"You need to realize nowhere in his record has Greg, that I'm aware of, ever instigated any physical attack on anybody," Passey said.
Matters left the military with an honourable discharge in 2009. Unable to work, he was surviving on a $123 a month military pension.
His financial troubles, chronic pain from a back injury suffered in Bosnia, and the conflict with his brother contributed to his illnesses, Passey said.
Andrew Kemp, the lawyer for the B.C. Attorney General and RCMP, asked Passey about his confidence that Matters would not act on his long list of threats.
"You would agree with the proposition though that even though he had not yet, to your knowledge, acted on any of his threats, there's always a first time?" Kemp asked.
"One has to look at past behaviour as a method to predict future behaviour," Passey replied.
"Greg had multiple opportunities to act in an aggressive manner toward individuals, and I had no history that it ever occurred, so it was unlikely he was going to act on those threats because in between, once he settled down, the threats dissipated."
"Unlikely is different than never, though," Kemp said.
Kemp pointed out that Matters's previous therapist, who treated him for two years, took threats against her seriously enough to call police.
Under questioning from jurors, Passey said Matters's PTSD made it very difficult for police to deal with him.
"It made it very difficult for both parties in this," he said.
Asked if he had any recommendations that might prevent similar deaths in the future, Passey said every police officer should be trained to deal with PTSD and other trauma-related disorders.
"This should be taught at Depot and should be something that's taught every time an officer needs to requalify," he said.
"They need to requalify on regular basis with regards to baton use, Tasers, firearms, etcetera. There should be a course specifically to educate officers about this disorder."
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