VANCOUVER -- The Conservative government is providing courts with new powers to lock up people found not criminally responsible for their crimes due to mental problems.

Prime Minister Stephen Harper says the government's latest tough-on-crime legislation targets people who are found to be too dangerous to be released.

"The new legislation introduced today focuses on victims and places public safety at the forefront of decision-making," Harper said in Metro Vancouver, where he was joined by Justice Minister Rob Nicholson and Heritage Minister James Moore.

"This will ensure that 'not-criminally-responsible' accused people found to be too dangerous to be released are no longer a threat to their victims or Canadian communities."

Courts will be allowed to designate people who are found not criminally responsible as "high risk" -- meaning they could be held for up to three years before their mental status is reviewed to see if they are fit for release.

Offenders with such a designation could not be released until a court agrees. They would never be given unescorted passes and "could only obtain an escorted pass in narrow circumstances," said the government.

Currently, a review board -- chaired by a judge and including mental health professionals -- assesses such cases on an annual basis.

The controversy around the issue has cropped up recently. Next Friday, a man found not criminally responsible for the deaths of his three children in 2008 in Merritt, B.C., is slated for a psychiatric review.

Allan Schoenborn asked for, and got, a delay last November for his review. Schoenborn is confined to the Forensic Psychiatric Hospital in Port Coquitlam, but is allowed an annual review of his case to determine whether he should be given any liberties.

In 2011, the B.C. Review Board concluded the lead psychiatrist at the Port Coquitlam facility could decide whether to give Schoenborn escorted leave.

But the psychiatrist said later he didn't know Schoenborn's ex-wife also lives in the community, prompting the B.C. government to push for changes to the Criminal Code to scrap the mandatory yearly review.

In mid-December last year, a former Quebec cardiologist was released 18 months after being found not criminally responsible for killing his two children in 2009.

"We've heard from Canadians loud and clear, something here is very wrong," Harper said Friday.

Under the existing system, the board assesses the individual and designs a plan "that both protects the public and attempts to provide opportunities to treat the underlying mental disorder."

Friday's news release says the new system "would explicitly make public safety the paramount consideration in the court and the review board decision-making process."

The new legislation will also "clarify" the meaning of someone being a significant public threat. It will now include offences that are "criminal in nature but not necessarily violent in order for restrictions to be imposed on an accused."

The Supreme Court of Canada previously ruled in 1999 that review boards must order an absolute discharge for people found not criminally responsible as long as they do not pose a significant threat to the public.

The existing law also states that courts and review boards must choose "the least onerous and least restrictive" conditions for the accused.

The current standard, according to Justice department documents, is to "balance the dual roles of protecting the public and treating the accused in a fair and humane manner that respects his or her rights."

In a background document on its website, the Justice department states: "It is a fundamental principle of the Canadian criminal justice system that an accused must possess the capacity to understand that his or her behaviour was wrong in order to be found guilty of an offence."