VANCOUVER - A man accused of killing a 13-year-old girl in a British Columbia high school has been declared mentally fit to stand trial after a change in medication his lawyer described as a "miracle."

Gabriel Klein suffers from schizophrenia, auditory hallucinations and paranoid delusions and will remain at a psychiatric hospital during the trial instead of going to a pre-trial centre.

His lawyer Martin Peters told a B.C. Supreme Court judge on Thursday that his client has made "tremendous gains" since he was declared unfit last April.

"From the standpoint of being able to interact with him, they're extraordinary — a miracle of pharmaceuticals," Peters said.

Klein was 21 in November 2016 when he allegedly walked into an Abbotsford high school and stabbed Letisha Reimer to death and wounded another girl.

He has been charged with second-degree murder and aggravated assault and a six-week trial has been scheduled for October.

Associate Chief Justice Heather Holmes declared him unfit for trial last April because his psychiatric symptoms were impeding his ability to understand proceedings.

The B.C. Review Board held hearings in July and September and concluded he was unfit. During a hearing on Jan. 15, the board unanimously agreed he was ready for court.

Both the Crown and defence asked Holmes on Thursday to declare Klein fit and make an order allowing him to stay at the psychiatric hospital. The judge agreed to both, saying that it would be best if Klein is held at the facility where he has made "great gains."

"There will be the best possible chance that Mr. Klein will remain fit to stand trial and the trial will be able to complete as it should," she said.

Crown counsel Rob Macgowan told the judge that a psychiatrist has concluded that Klein's symptoms have subsided in recent months due to the new medication.

He has reported a reduction in the voices he hears and his thoughts processes appear logical, Macgowan said, adding Klein testified at the recent review board hearing that he was "feeling better."

"Mr. Klein said the medication allowed him to — quote — 'focus on what's going on,' " he said.

Klein was able to answer questions appropriately about court personnel and their roles and he understands the proceedings are separate from his delusions, Macgowan said.

He said Klein should remain at the psychiatric hospital because he'd had delusions specifically about the pre-trial centre and has threatened not to take his medication if sent there.

It's also best for Klein's mental health if he doesn't take any illicit substances, and it would be "naive" to assume that such substances aren't available at the pre-trial centre, Macgowan said.

"There is a high public interest in seeing this matter conclude without being once more sidetracked over concerns of fitness," he said.

Reimer's family did not attend the hearing. There is a publication ban on the identity of the injured girl.

Peters said outside court that Klein was obviously unable to focus before the change in medication.

"He had voices in his head, screaming at him all the time, 24 hours a day. It's very hard to concentrate on a conversation, let alone evidence in court, when there's a further dialogue going on in your head," he said.

Peters said he expects to argue at trial that his client is not criminally responsible for the crime because of a mental illness.

— Follow @ellekane on Twitter.

News from © The Canadian Press, 2019