11/06/2017 13:27 EST | Updated 11/09/2017 13:25 EST

'Fight of my life:' Calgary officer testifies at arrest assault trial

CALGARY — One of three police officers accused of assaulting a man during an arrest says he thought he was in the fight of his life.

Const. James Othen testified in court Monday that his adrenaline was pumping and he feared for his safety as he and about a half dozen other Calgary officers were trying to take down Clayton Prince on July 30, 2016.

"My stress is at an all-time high," the officer testified. "I think I will be in the fight of my life."

Othen and constables Kevin Humfrey and Michael Sandalack have all pleaded not guilty to assault causing bodily harm.

The Alberta Serious Incident Response Team, the provincial body that investigates serious police actions, said Prince had broken ribs, a collapsed lung, a facial cut and significant bruising.

Prince was chased by police after he ran away from a traffic stop. Charges of resisting arrest and possession of marijuana were later stayed.

Othen told court that his anxiety ramped up when he heard over the radio that one of his colleagues was chasing Prince through a sushi restaurant.

Defence lawyer Alain Hepner asked Othen to describe his past experiences patrolling a part of Calgary's downtown frequented by drug users.

Othen replied that over the years he had found himself in more than 10 foot chases — the most stressful situation an officer can encounter.

"Your stress level is through the roof because of the unknown," said Othen, who explained that in such cases it's possible the suspect has a weapon or is intoxicated.

He recalled arriving outside a jewelry store close to the sushi restaurant and seeing another officer with his gun drawn, further heightening the tension.

Othen said that, at one point, Prince started to move toward officers.

"I was like, 'Holy smokes' in my head, going, 'Here we go. This is going to be the fight.'"

ASIRT began investigating a month after the arrest when video from a police dashboard camera contradicted officer accounts.

Othen said it wasn't until after ASIRT showed him the footage that he realized his recollection may have differed from what actually occurred.

He said he had recalled Prince positioning his hands in such a way that it would have been difficult to handcuff him as officers were trying to arrest him. Othen said he also remembered kneeing Prince in the upper thigh and punching him four to six times in the head.

He said it was possible he started engaging with Prince just as the subject was being subdued.

In his cross-examination, prosecutor Jim Stewart asked Othen why he tackled Prince, kneeing him in the lower back, when it seems from the video that he was relenting.

"I thought I had taken him to the ground, sir," replied Othen, who added that once he saw the video, it was apparent Prince was actually already on the ground.

Stewart showed Othen a frame from the video and said it looked like Prince's hands were above his head at the time. Othen said he disagreed that was apparent from the image.

Othen and Humfrey also face charges of public mischief for allegedly making false statements.

Othen faces an additional charge of assault with a weapon for allegedly digging a key into Prince's neck.

On Monday, Othen denied that happened. He said it was a common practice of his to toss his keys into the footwell of his truck before pursuing a suspect on foot so that they wouldn't get lost. He did, however, tell the court that he had a handcuff key on him at the time.

Humfrey testified Monday that his recollection of events also differed from the video before he'd seen it.

He said he had previously thought he'd been part of a "dynamic takedown," a term he said does not have a firm definition.

"To me, it means taking a person from standing to the ground using any means necessary."

But after ASIRT showed him the footage he realized that wasn't the case.

Humfrey said he was focused on getting on control of Prince's left arm so that he could be cuffed behind his back.

He said it's tough to say how long that took, but it was more than 20 seconds and less than a minute.

"I can definitely say it took longer than I would have liked or anticipated."

The Crown concluded its case in August. Defence arguments are expected to finish later this week.