Richard Kachkar was behind the wheel of a snowplow that struck and killed Sgt. Ryan Russell on a Toronto street on Jan. 12, 2011.
The 11-year police veteran was trying to stop Kachkar when he was killed.
On Wednesday afternoon, a jury found Kachkar not criminally responsible in the officer's death.
The judge had told jurors during the trial that there was "no doubt" Kachkar drove the snowplow that killed the 35-year-old Toronto officer. What was at issue in the trial was the accused's mental state.
The verdict the jury delivered on Wednesday indicates that jurors believed that Kachkar could not appreciate what he was doing when Russell was killed, because he was mentally ill.
The CBC's Steven D'Souza reported that Kachkar showed no reaction to the verdict in court.
D'Souza said the courtroom was packed with members of Russell's family, as well as a number of police officers.
"As the verdict was read, you could see a lot of them shaking their heads and [the officer's wife] Christine Russell … immediately put her head down," he reported shortly after the verdict.
For now, Kachkar will remain in custody, until an Ontario Review Board hearing is held at some point in the next 45 days. That board will decide what psychiatric facility he goes to. The Russell family will have an opportunity to read victim impact statements at that time.
D'Souza reported that as Kachkar was led away, a friend of the Russell family told him to "go to hell."
Later in the afternoon, the slain officer's widow read a victim impact statement to the court.
She spoke of their son, Nolan, and how he asked at the funeral where his father was. She said her son is now beginning to understand.
"One night he was very upset," she said in the statement. "I asked him why he was crying and he said, 'Because daddy can't come down from heaven and read to me.' Just recently he told me, 'I'm not happy because I want daddy to come home."'
The slain officer's father, Glenn Russell, also read a victim impact statement to the court.
"You, Richard Kachkar, smashed my family to pieces," he said.
He said that Kachkar has "no idea how much grief and pain" he had caused.
"When you ran my son down with that plow and left him bleeding to death in the snow, a large part of myself died."
He also said there "isn't an hour of the day" that goes by that he does not think of his son.
"There is no closure ... trying to cope with it is an exhausting task."
The officer's sister, Tracey Russell, also spoke in court.
"It has been two years and the pain is still very much a part of our life now.... Ryan has a little boy, Nolan, he is a lovely baby ... [who] will never know his daddy."
Outside court, the officer's widow told reporters that she felt no closure as a result of the verdict in Kachkar's trial.
"I believe that Ryan deserved a lot better than this and he was serving and protecting all of us and he was killed in the line of duty. Nothing changes that," she said on Wednesday afternoon.
'He was very dear to us,' police chief says
At Toronto police headquarters, Chief Bill Blair said the jury had a tough job and police are thankful for the job they did.
Blair said there wasn't any verdict that would bring a sense of satisfaction to the people Russell left behind.
"We lost a man and a family lost someone very, very dear to them and he was very dear to us," he said Wednesday.
"And the tragedy of that is not relieved by this verdict. But we understand the nature of the verdict. It was a tough case."
Mary Vruna, the lead detective on the case, also said that the verdict would not change the loss that Russell’s family and friends must live with.
"It doesn't matter what decision they would've come up with, whether it was not criminally responsible or a conviction for murder, it doesn't change the loss that the Russell family, Ryan Russell's friends and Ryan's wife and son will carry with them for the rest of their lives."
Testimony from police officers, psychiatrists
Kachkar's trial began in February. The jury began deliberating on Monday.
The jury heard testimony from police officers, paramedics and other people who saw or interacted with Kachkar on the day that Russell was killed.
Jurors also saw video of a barefoot Kachkar fleeing a shelter in downtown Toronto before his deadly interaction with the police officer.
They also heard testimony from a man who saw Kachkar run out of a Tim Hortons and take off in the snowplow.
Footage captured on Russell's dashboard camera was also shown to jurors, as well as audio recorded during the doomed officer's last radio call.
"He's coming after me. Hold on," Russell said.
The defence called three psychiatrists who each diagnosed Kachkar as being in a psychotic state and not criminally responsible when the officer was killed.
"These are not run-of-the-mill psychiatrists, these are people who have a lot of experience — one of the individuals had assessed Russell Williams," D'Souza reported. Williams is the former CFB Trenton base commander who was convicted of murdering two women and sexually assaulting others.
"So, these are people who have seen a lot before."