TORONTO -- Ontario is narrowing the scope of mandatory investigations carried out by the province's primary police watchdog, with the Progressive Conservative government framing current rules as inherently anti-police.

The change involving the Special Investigations Unit is part of legislation introduced Tuesday to overhaul police oversight regulations. It comes after the government paused implementation of a law from the previous Liberal regime that enhanced the mandates of Ontario's three police oversight agencies -- the SIU, the Office of the Independent Police Review Director and the Ontario Civilian Police Commission.

Currently, the SIU investigates circumstances involving police and civilians that have resulted in serious injury, death or allegations of sexual assault. That could include cases of suicide or situations in which a person dies after a medical incident.

Under the new legislation, the SIU would limit investigations to when police use of force results in serious injury or death, as well as when an officer has shot at a person or if there is a reported sexual assault, and would have to wrap up investigations within 120 days.

Attorney General Caroline Mulroney said the changes would focus the SIU's mandate to what it was originally created to do: investigate suspected criminal activity.

"That's actually not the case today," she said at an announcement in Oakville, Ont. "If a police officer tries to stop a suicide attempt but is unsuccessful, he or she is treated like a suspect ... If a police officer responds to a violent crime, tries to perform CPR but is unable to save the life, he or she is treated like a suspect. This is not what the SIU should be doing."

Community Safety and Correctional Services Minister Sylvia Jones said the Liberal changes to police oversight laws actively undermined policing efforts and public trust in officers.

"Police will no longer be treated like they're guilty until proven innocent," she said.

Under the Liberal legislation, officers who didn't comply with SIU investigations could be fined up to $50,000 and/or be sent to jail for up to one year -- those fines will be drastically lowered, to $5,000 for a first incident and $10,000 for a second.

As well, the previous legislation allowed police chiefs to suspend officers without pay, and while Jones said that power is being maintained, she said the legislation will clarify the circumstances.

Many of the policing updates brought by the Liberals stemmed from a sweeping report on police oversight conducted by Appeal Court Justice Michael Tulloch.

The new Tory bill would also eliminate the Ontario Civilian Police Commission in order to create a single body to handle public complaints about police -- the Office of the Independent Police Review Director would become the new Law Enforcement Complaints Agency. It would receive and screen public complaints about police officers and assign an investigation to a police service or an agency investigator.

The Police Association of Ontario said it hasn't been able to review the legislation before its introduction, but it welcomes the announcement.

"We are optimistic that this Act will restore fairness and respect for professional policing in the province, make oversight more effective, and improve governance, training, and transparency for the profession," the group said in a statement.

The Canadian Civil Liberties Association said the changes gut police oversight.

"The changes to police laws that stand the test of time are ones that are welcomed by neither the police unions, the police chiefs and the community groups," said executive director Michael Bryant, who is a former Liberal attorney general.

"Usually there's water in the wine for all the parties. Not this one. This one is a complete capitulation to the police associations with little to no collaboration with community groups."