TORONTO -- Ontario plans to crack down on frivolous strategic lawsuits aimed at intimidating and muzzling critics on matters of public debate.

New anti-SLAPP -- or Strategic Litigation Against Public Participation -- legislation was introduced Tuesday by the governing Liberals, who say it's time Canada's most populous province join Quebec in rooting out such nuisance lawsuits.

They have a "chilling effect" on public debate, said Attorney General John Gerretsen.

"A citizen's confidence in their justice system and their willingness and ability to participate in a democratic society are inextricably linked," he said.

Most SLAPP suits are defamation claims that have little or no merit and are dropped before proceeding to trial, the Liberals say. They can also silence groups that don't have the money to defend themselves in court.

Laws to protect citizens against strategic lawsuits are common in the United States, said Gerretsen. British Columbia's legislation was repealed.

Ontario's environmental commissioner has long complained that such intimidating legal tactics are being used by big developers to weaken groups fighting to protect natural areas.

He cited one case in which a group of residents who opposed the proposed Big Bay Point Resort on the shores of Lake Simcoe faced a $3.2-million claim for costs by the developer.

The claim was denied by the Ontario Municipal Board, but the cost of defending themselves ended up totalling more than $1 million, according to a lawyer involved in the case.

The Liberals finally put together a panel to make recommendations for anti-SLAPP legislation, which delivered its report in 2010.

Under the proposed law, courts could fast-track the review process for lawsuits that are alleged to be strategic.

One of the parties can file a motion to dismiss the case, which would have to be heard by the court within 60 days, Gerretsen said. The legislation also includes a legal test that a judge could use to quickly decide whether or not the case should be dismissed.

"In applying the test, the courts would seek to balance the interest at stake with an eye not only on the technical merits of the plaintiff's case, but on the value of free expression on matters of public interest," Gerretsen said in the legislature.

The case would be allowed to continue where the plaintiff is likely to suffer serious harm, he said.

If little or no harm is likely, then the technical merits of the case would yield to the value of public democratic debate and the suit would be dismissed, he added.

The legislation contains similar provisions for proceedings in administrative tribunals like the Ontario Municipal Board, Gerretsen said.

Submissions for costs would also have to be made in writing, unless a tribunal determines that it's "likely to cause the party significant prejudice," the five-page bill states.

The proposed law would also amend Ontario's libel and slander law to better protect free expression on matters of public interest, he said.

The legislation is slightly different than Quebec's, where judges don't need a motion to decide if the case in front of them is abusive, said John Gregory, general counsel to the Ministry of the Attorney General who wrote much of the legislation.

"The court doesn't get to decide on its own," he said.

Strategic lawsuits are a national issue, said Roy McMurtry, a retired judge and Ontario attorney general under former Tory premier Bill Davis.

"I think it's an issue in every province," he said.

"To what extent it's an issue in other provinces, I don't know. But it's an important issue. It's a complicated issue."

The minority Liberals would need the support of at least one of the opposition parties to pass the legislation. It's unclear when it may come to a final vote, since the legislature is expected next week to break for the summer.

The New Democrats and Progressive Conservatives wouldn't say whether they'd support the bill. Both said they welcome legislation to stop SLAPP suits, but noted that the government has dragged its feet on the issue.

NDP Leader Andrea Horwath, who introduced an anti-SLAPP private member's bill in 2008, said her party has been pushing for it for five years.

"Really? Five years to do something that everybody agrees needs to be done?" she said.

Gerretsen acknowledged that SLAPP suits have been an issue in Ontario for some time, going as far back as eight years ago when he was minister of municipal affairs and housing.

"It's taken a lot of work," he said.

"We've reached a stage now where we think legislation is required in that regard."