Three psychiatrists are expected to testify in the murder trial of Richard Kachkar, as his lawyer argued the man is not criminally responsible for the death of Toronto police officer two years ago.

The defence opened its case in a Toronto courtroom Tuesday, telling jurors that Kachkar was in a psychotic state when he stole a snow plow and fatally struck Sgt. Ryan Russell, 35.

The judge in the trial has told the jury that there is "no doubt" Kachkar was driving the stolen plow on Jan. 12, 2011, when it hit and killed Russell. The jury must now determine what was his state of mind at the time and if he intended to kill Russell.

If the jury finds that Kachkar is criminal responsible for the death, he is guilty of either first-degree murder or manslaughter.

Lawyer Bob Richardson told the jury that if they find Kachkar is not criminally responsible, it doesn’t mean he will walk free.

The 46-year-old is charged with first-degree murder and dangerous driving in the snowplow rampage case.

The jury was told Tuesday that the dangerous driving charge has been severed from the case and will be heard a later date.

The Crown had wrapped up its case against Kachkar earlier in the day.

With files from The Canadian Press