Nine different organizations, including their multiple provincial organizations, say changes to the Not Criminally Responsible regime for mentally ill offenders have been made without evidence or input from mental health workers.
They're offering to help the government redraft bill Bill C-54 so that it continues to help victims but doesn't undo years of progress.
They say Bill C-54 has been framed by the Conservatives in such a way that it stigmatizes millions of Canadians who will never commit a crime.
The Schizophrenia Society of Canada says the government message is to be afraid of people with a mental illness.
Prime Minister Stephen Harper used Allan Schoenborn's horrific murder of his three children in 2008 to promote the government legislation this spring, but a trio of top mental health experts say the bill would do absolutely nothing to prevent such crimes.
Dr. Paul Fedoroff, president of the Canadian Academy of Psychiatry and the Law, says the bill may actually make society less safe.
"This legislation appears to have arisen to fix a problem that doesn't exist," said the psychiatrist from the Royal Ottawa hospital.
He said current review boards who oversee offenders that are declared Not Criminally Responsible "have been extremely effective," and have far, far lower recidivism rates than the federal prison system.
Justice Minister Rob Nicholson's office put out a release framing the legislation as helping victims.
"Victims are concerned that their safety is not being specifically taken into consideration by Review Boards when they make a disposition," said the release. "Victims are also concerned that they often have no way of knowing if and when an NCR accused was going to be given access to the community and were afraid they would unexpectedly run into them without being adequately prepared."
Mental health professionals say they "wholeheartedly" endorse the changes that address victims' concerns, but say the good will be undone by the bill's focus on also punishing offenders.
The inability to monitor patients to ensure they stay on their medications after they leave supervision is one of the most often-cited reasons for locking up NCR offenders indefinitely.
But the Conservative plan to stop supervised community visits and other measures designed to ease offenders who are deemed "high risk" back into society may backfire, said Fedoroff.
"Paradoxically the new legislation will make it harder to ensure that patients don't drop out of treatment," said the psychiatrist.
Mental health professionals say violent crime by the mentally ill comprises less than one per cent of cases but the government's focus dredges up the worst fears in society.
"The bill in the way it's been cast really does stigmatize millions of Canadians," Chris Summerville, CEO of the Schizophrenia Society of Canada, said at a news conference on Parliament Hill.
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