The Hamilton police officer who shot and killed the driver of a stolen van says he was left with no "other options" but to fire his gun on that cold February day.

At an inquest into his actions, Ryan Tocher told the jury he came to this conclusion while hanging from the hood of the van, the driver, Phonesay Chanthachack, lurching the car forward in an attempt to evade police.

"Whether he takes my life or injures me, he doesn't care," Tocher said, explaining he was convinced that Chanthachack, who was known to police, was determined to flee at all costs.

The officer made the split-second decision to fire a shot through the windshield, hoping to "immobilize" the driver.

When Chanthachack continued to move the car forward, Tocher pulled the trigger again, this time through the side window, the officer said.

"What's my other option? To be dragged at whatever-kilometres-per-hour?"

After firing his gun a second time, Tocher was thrown from the van, which then careened into a post.

Chanthachack, 27, died from his injuries in hospital later that day.

Mandatory inquest

Tocher's account came on the fourth day of the inquest at the John Sopinka Courthouse in downtown Hamilton, while he was being questioned Graeme Leach, a lawyer for the coroner.

Three officers who were also involved in the operation testified earlier this week.

In June, the Ontario Special Investigations Unit cleared Tocher of any wrongdoing, but the inquest into the shooting was called in accordance with the province's Coroners Act.

Related: Controversial officer at centre of inquest into fatal police shooting

The incident in question occurred at about 1 p.m. on a Feb 13, 2012, during lunch hour for many students at nearby Bishop Ryan Catholic Secondary School.

Tocher, along colleagues Mark Petkoff, Denise Leonard and Ryan Howard, were monitoring a known stolen van parked at an apartment building near the intersection of Albright and Quigley roads. All members of the police's Break and Enter, Auto Theft and Robbery (BEAR) unit, wore plain clothes and drove unmarked vehicles.

In his testimony, Tocher recalled reclining in a blue Dodge Caravan, looking out for any suspicious activity. He said he hadn't expected anybody to approach the vehicle, adding the lot was a "dumping ground" for stolen cars.

He said he'd expected his team to move on to another target when the call came through on his police radio. The vehicle was in motion, heading for a driveway along Albright Road.

Tried to block the van

Tocher said he drove his van to the parking lot entrance in an attempt to block the stolen van from entering traffic. Howard positioned his vehicle to the rear of the van, Tocher said, leaving the suspect with little room to escape.

Wearing a black blazer and a navy blue tie, he told the courtroom he jumped out of the car and lifted his North Face jacket to reveal his pistol and his police badge.

He said he'd expected to serve as a decoy, his role to distract Chanthachack while Howard approached the driver's side door from behind to "effect the arrest."

'I didn't want [the gun] to be used. I just wanted it available to me.'

—Ryan Tocher

But when Howard didn't emerge, Tocher approached the van from the passenger side, assuming a "safe space" from which he could easily move if the car were to jolt forward.

"'Police!' " he recalled yelling. "'Put your hands up!' "

It was at this point, Tocher said, that he removed his gun from its holster.

"Because [Chanthachack] is in a 2,000-lb. car which could be used as a weapon, I decide to draw a firearm," Tocher said.

"I didn't want it to be used. I just wanted it available to me." 

'Please stop the car'

That Chanthachack didn't submit to an arrest came as a big surprise.

"I had no reason to believe he would run," Tosher told the inquest. "He had no history of it and I had no reason to believe he was armed."

But things didn't turn out how the constable and his team had planned.

"He drops the car into reverse, pushing Howard's car back," he said, "and angles the car toward me."

Tocher said he could hear the sounds of the van transmission jerk as it shifted into drive, a sign that Chantachack intended to bolt van forward onto Albright Road. He tried a "football dodge," he said, in an attempt to get out of the way.

He wasn't successful. Instead, he said, the "momentum pushes me on top of the hood of the car."

At that moment, Tocher said, he hung onto the hood and repeatedly yelled at Chanthachack to "stop the f---ing car."

"In my head, I'm thinking, please stop the car so I don't have to do any more than what's gone on."

Possible recommendations

During his testimony on Friday morning, Tocher repeatedly defended his decision to open fire.

'No amount of training would have gotten me out of the way of that car.'

—Ryan Tocher

"What happened here was terrible, but I don't know what other options I was left with."

However, when Leach asked whether new recruits could receive training that would help them in his situation, Tocher offered few suggestions.

"There's one variable that you can't control, and that's the bad guy," Tocher said.

"No amount of training would have gotten me out of the way of that car." 

The inquest is expected to last for 10 days. A five-member jury will examine the events surrounding the shooting and may make recommendation on how similar deaths could be prevented.