Testifying at the hearing into three separate police shootings, Const. Kyle Paterson said he had no choice but to pull the trigger when Reyal Jardine-Douglas came at him.
"It's very clear that he's coming after me, and I don't know why," Paterson testified.
"I'm stuck in a situation where I feel like I'm going to die."
On an afternoon in August 2010, Paterson and Const. Ehsan Haghshenas responded separately to a call that an emotionally disturbed man had boarded a city bus.
The officers hemmed the bus in with their cruisers. Paterson says he calmly got on board intending to speak to Jardine-Douglas quietly. Haghshenas was seconds behind.
On board, Jardine-Douglas, 25, suddenly brandished a knife and began bearing down on Paterson, a scene captured on surveillance video.
"Drop the knife! Drop the knife!" Paterson ordered.
Jardine-Douglas, without saying a word, kept coming as the officers backed off and away from the bus, barking orders to comply with their demands.
Paterson said he kept moving backwards to put some distance between him and the assailant, but found himself up against a hedge.
"I'm essentially left with nowhere else to go. I was essentially cornered," he said.
"I discharged my firearm at a very rapid pace."
Paterson fired three shots, the inquest heard. Jardine-Douglas fell to the ground, his eyes still fixed on Paterson, the officer testified.
When he tried to get up, Paterson shot him once more. This time he dropped and stayed down.
Paterson said it all happened so quickly, there was no time to do anything other than use his gun.
"There was only enough time to respond essentially one way," he said.
The inquest is also examining the deaths of Sylvia Klibingaitis and Michael Eligon. All three were holding sharp items and had mental-health issues when Toronto police officers shot them dead.
In his testimony earlier Thursday, Haghshenas said events unfolded too quickly to try to talk Jardine-Douglas down.
"Me standing there and saying, 'Let's calm down,' will just get me stabbed," Haghshenas testified.
"He was going to kill my partner."
The inquest has previously heard that everything was calm on the bus until Paterson got on.
Haghshenas said he was just getting on the bus when the situation changed.
"I hear Const. Paterson saying, 'Whoa! Whoa! Whoa! Drop it!' Haghshenas said, as they both backed off and drew their guns.
"A six-foot-two guy, 260 pounds. He's coming at us with a knife. I would get off the bus."
Haghshenas said the man gave him a blank look, then turned his attention to Paterson.
"It seemed like he had a mission and he wanted to kill Const. Paterson."
In cross-examination, John Weingust, lawyer for the Jardine-Douglas family, asked why the officers didn't talk quietly to the mentally ill man or try to calm him down as they are trained to do.
That option wasn't there, Haghshenas testified.
Jardine-Douglas, he said, had every chance to change direction and leave the scene rather than go at the officer.
"We probably would have followed and tried to explore other options," the officer said.
"He might not have been shot."
The inquest adjourned abruptly without any explanation and was to continue Friday with Paterson facing cross-examination.
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