A woman who stabbed a Watson Lake support worker on June 27, 2015 is not criminally responsible for her actions because of a mental disorder, a judge ruled Tuesday.

The ruling means that while the judge recognized Ashley Chief did commit the stabbing, she won’t be sentenced for attempted murder because she couldn’t tell her actions were morally wrong.

Instead, the Yukon Review Board will hold a hearing to determine whether the 29-year-old should be sent to a hospital or can be managed in the community.

Judge John Faulkner ruled the report by psychiatrist Jeannette Smith showed Chief’s attack was fuelled by an internal mental disorder, not drugs.

Chief had told the RCMP she had ingested LSD the day of the attack.

While it makes no difference from a medical point of view whether a psychosis is induced by drugs or a person’s mental disorder, the difference is important from a legal standpoint, Faulkner noted.

A mental disorder that prevents somebody from recognizing an act is morally wrong will lead to a not criminally responsible finding.

But self-intoxication – ingesting drugs or alcohol – can’t be used as a defence in the criminal justice system.

Crown prosecutor Eric Marcoux zeroed in on that point during his final submissions Tuesday morning.

Quoting from Smith’s reports, he noted the psychiatrist couldn’t determine the extent to which the LSD had influenced Chief that day.

In his decision, Faulkner took note of Marcoux’s point.

Even if he was to consider the highest effect LSD could have had on Chief, the finding is still warranted, he said.

Chief has a lengthy history of mental disorder, and had been hospitalized a number of times.

She was previously prescribed anti-psychotic medications.

A month before the attack, she stopped taking them.

From that point on, Chief started having delusions about being crucified, and communicating with bears and dolphins.

Even after her arrest, she remained angry and violent at the Whitehorse Correctional Centre (WCC), and had to be sent to Whitehorse General Hospital.

There, medications she took quickly calmed her down.

All these elements support a mental disorder-fuelled attack, the judge said.

The attack Chief perpetrated that day was “bizarre, unprovoked and unexplicable,” Faulkner noted.

Even if her explanation during her second interview with the psychiatrist that the attack was self-defence was made up, the judge said, it’s clear she was suffering from a mental disorder and could not appreciate the wrongness of her action.

That day, her mother had called the RCMP because Chief was behaving strangely.

She was driven to the Help and Hope shelter in Watson Lake.

After filling paperwork with a support worker, Chief came back with a large butcher knife.

She lunged at the worker, who ran to the backyard.

Chief followed her there and stabbed her multiple times, at one point almost cutting her throat.

The worker was able to escape and lock Chief out in the fenced backyard.

Videos of the incident were shown to the court.

These were “extremely difficult to watch,” Faulkner said.

“The attack was terrifying, to say the least,” he said.

The victim – whose name can’t be published because of a publication ban – has recovered from her wounds, he said.

Chief will remain at WCC pending the review board hearing.