The Winnipeg police officer who used a Taser on Michael Langan in 2008 told an inquest Wednesday into the 17-year-old's death that he felt he was in imminent danger.

Const. Ryan Naismith testified that Langan was holding a knife when he and his partner approached the teen in their cruiser in a back lane near William Avenue on July 22, 2008.

Naismith said he yelled at Langan several times to drop the weapon, which the officer described as a knife with a three-inch blade and a wooden handle.

"He had a diabolical smile on his face," Naismith said of Langan on Wednesday. "There was no joking in his face."

He added, "I immediately yelled at him to drop the knife four or five times. He never moved at all."

Naismith said he was sitting in the passenger side of the cruiser, and Langan was about 1.5 metres away from him, so he pulled out the Taser in the hopes the teen would drop the knife.

"He was well within range to apply a knife attack against me," he said.

After Naismith shocked Langan with the Taser, the teen dropped to the ground immediately.

Langan died in hospital a short time after the confrontation with police.

Langan's father stormed out of the inquest room during Naismith's testimony on Wednesday morning.

As the inquest began on Monday, a local businessman testified that Langan broke into his car on the day of the incident to steal a pair of binoculars.

Hartley Klapman said after a brief confrontation in the parking lot, he followed Langan in his vehicle until the teen produced a knife and waved it around.

Pepper spray wouldn't have been as effective: officers

Both Naismith and his partner, Michael Temple, were asked why a Taser was used instead of pepper spray or a baton.

Temple testified on Tuesday that pepper spray wasn't used in Langan's case because it's not as effective when a suspect is too close to officers and poses a threat.

On Wednesday, Naismith said there was a high risk of himself being contaminated with the pepper spray if he had deployed it within such close quarters.

As for using a baton, Naismith said there wasn't enough space inside the vehicle to deploy it.

Temple testified that the officers came close to Langan in the cruiser, thinking they were going to chase him on foot.

Had the officers known from the start that Langan was carrying a knife, they would have tried to contain the suspect from a distance and called for backup, he told the inquest.

Naismith said his only options in that case were to use a firearm or a Taser, but he had intended to use the electric stun gun in the hopes the suspect would drop the knife.

"If he had run, I would have left it in the car," he told the inquest. "I wouldn't have chased him with a Taser in my hand."

Before the hearing adjourned for lunch, Langan's mother asked Naismith if police had taken a photograph of the knife her son allegedly had at the scene. Naismith said no.

The inquest was told that testimony about the evidence would come at a later time.

Testimony hard to hear, mom says

Langan’s mother, Sharon Shymko, said the testimony from the officer was tough to hear.

"It's reliving it all over again, but I do want answers, you know," she said.  

She said she believes the officers made a mistake.

“Obviously he didn’t run away from cops when the cops came there. He just stood there, and the police said he could have run but he didn’t,” she said. “He wouldn’t do that.”

Shymko said the officers could’ve used different means to arrest Langan.

The inquest's first phase wrapped up on Wednesday afternoon and was set to resume on June 16.

With files from the CBC's Nelly Gonzalez