The police officer suffered second and third degree burns to his right leg, between his ankle and knee, as a result of the incident at Brindabella Business Park in September last year.

A Canberra judge found David Percival Burnett, 44, not guilty of a number of offences, by way of mental impairment, and ordered he submit himself to the jurisdiction of the ACT Civil and Administrative Tribunal so it could make a mental health order.

In September, Mr Burnett faced a judge-alone trial in the ACT Supreme Court on charges of recklessly inflicting grievous bodily harm, property damage, and dangerous driving.

The court heard Mr Burnett had been attempting to return to work in September last year after time off due to a stress-related condition.

He became frustrated with the process so armed himself with three Molotov cocktails, two knives, a tomahawk, and a pick handle, and drove to Majura about 2.55pm, where he crashed his ute into metal bollards in front of one of the business park's buildings.

Mr Burnett went into the building and used the pick handle to smash a number of items, including glass doors and windows.

When police arrived, he urged them to shoot him.

During the stand-off, petrol from one of the Molotov cocktails spilled and caused an officer's leg to be engulfed in flames, leaving him with serious burns.

Mr Burnett then dropped a second petrol bomb, which narrowly missed a sergeant, before he was stopped with a stun gun.

In a police interview soon after, Mr Burnett told police he wanted to be shot, and took the weapons to present "a credible threat".

During the trial, the court heard Mr Burnett had been diagnosed with a major depressive disorder, which was likely to have impaired him at the time of the offences.

Mr Burnett's psychiatrist, Dr Jeremy O'Dea, said the mental illness could have meant the defendant could not control his actions or realise they were wrong.

The prosecution disputed the evidence, arguing Burnett's attempts to return to work showed he had been functioning with a moderate degree of sense and composure.

But Acting Justice David Robinson, in a decision published earlier this month, accepted the expert evidence that, at the time, Mr Burnett had been suffering from a major depressive disorder that "arose from an underlying pathological infirmity of the mind and hence was a 'mental illness'''.

The judge returned a verdict of not guilty by reason of mental impairment to all charges.

"I find, on the balance of probabilities, that at the time of the conduct in question the accused has established that he did not know that his conduct was wrong.

"He was unable to reason with a moderate degree of sense and composure about whether his conduct, as seen by a reasonable person, was wrong."

Acting Justice Robinson also found that Mr Burnett had no intention of harming anyone other than himself during the incident.

"Reduced to simple terms, his plan was to commit suicide by being shot dead by police … as a result of a workers compensation/resumption of employment dispute.

"I also accept that the accused armed himself … to create a credible threat and hoped that by doing so police would kill him."

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