TORONTO -- Jurors will have to weigh the mental state of a man who killed a Toronto police officer with a stolen snowplow and shouted about the Taliban, Chinese technology and a microchip in his body, court heard Monday.

Richard Kachkar, 46, has pleaded not guilty to charges of first-degree murder and dangerous driving in the death of Sgt. Ryan Russell. He sat unmoving during the first day of his trial, with his shoulders hunched over and staring at the floor.

"There will be no dispute that Mr. Kachkar was the person who was driving the truck," Ontario Superior Court Justice Ian MacDonnell told jurors. "That is, this case is not a whodunit."

The Crown alleges that Kachkar -- barefoot and wearing no jacket -- purposely drove the snowplow in the wrong lane toward Russell's marked cruiser, with its lights flashing, in the early morning of Jan. 12, 2011.

After Russell got out of his car and fired three shots at the snowplow Kachkar accelerated toward the officer, hitting him, Crown attorney Christine McGoey told the jury in her opening statement.

The plow hit Russell in the leg, knocking him off his feet and then it hit him in the head with such force that it fractured his skull, she said. As Russell lay in the snow, unconscious and bleeding from the head, the plow did not stop or slow down, she said.

"It is the Crown's position that he meant to cause Ryan Russell's death," McGoey said.

Russell's widow, who sat in the front row of the packed courtroom, said later that the start of the trial has stopped her healing and brought her pain back.

"It's not easy to sit there and sit so close to someone you know has done so much harm," Christine Russell said outside court. She thanked people for the support she and her now four-year-old son have received.

Kachkar had been living in St. Catharines, Ont., but came to Toronto to look for work after he felt he was not welcome around his estranged wife and two children, McGoey said. He was staying at a shelter in St. Catharines and asked a fellow resident, "Do you think if I do something bad, will God still love me?" McGoey said.

He also stayed at a shelter in Toronto the night before Russell's death, and asked one of the staff there to call the RCMP because he thought he was "going to do something bad," McGoey said. Kachkar decided after a few minutes that he no longer wanted to call police, she said.

Around 5 a.m. the next morning, Kachkar stole the truck with a plow attached at a Tim Hortons as two workers with a snow removal company stopped for a coffee break, McGoey said.

One of those workers testified Monday that he noticed Kachkar in the coffee shop with "messy hair" and wearing no shoes or socks.

After stealing the snowplow, Kachkar drove into a Maserati and Ferrari dealership window and made several U-turns, driving on the opposite side of the road and crashing into cars, McGoey said.

He shouted at passersby and other nearby witnesses, asking if they wanted rides, McGoey said. To one he "screamed something about Chinese technology," she said. To another who asked why he was offering a ride, he said, "You'll be on Facebook," McGoey said.

To yet another passerby he yelled, "I'm going to get you," she said.

Shortly after fleeing the scene of Russell's death he opened the door and shouted something about shots being fired and the Taliban to two paramedics who were en route to help Russell, McGoey said.

Ultimately emergency task force officers were able to stop Kachkar, McGoey said, but not before the plow hit two more cars, crossed into oncoming traffic and hit a garbage truck. The ETF officers got out, ordered Kachkar to get out of the plow and used Tasers, but he would not comply, McGoey said.

Instead, Kachkar accelerated and pinned an ETF officer's leg between the plow and the garbage truck, she said. It was at that point that another officer shot Kachkar twice and as they pulled him from the vehicle he "said something about his sister being the reason he did this or that it was her fault," McGoey said.

Kachkar told a paramedic and another man who was tending to his injuries that he was concerned they were going to poison him or put a microchip in his body, and "something about Russian Facebook, the government and 911 and said it was all a Russian video game," McGoey said.

No alcohol or drugs were found in Kachkar's system other than a trace amount of cannabis, she said.

Two detectives spoke to Kachkar on Jan. 25, 2011, after he was released from hospital where his injuries were treated. Kachkar told them he didn't know what happened, that he was confused and it was an accident, McGoey said.

"Obviously I'm sick," Kachkar told the officers, McGoey said.

The trial is expected to last two months.