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The premiers called on the federal government to withdraw its legal argument to the Supreme Court ‘immediately.’Sean Kilpatrick/The Canadian Press

Five provinces – including Quebec, Ontario and Alberta – are calling on Prime Minister Mark Carney to back down in a landmark Supreme Court of Canada case that revolves around the Charter’s notwithstanding clause and governments’ power to override the rights of Canadians.

In a legal filing in mid-September, Ottawa asked the top court to impose restrictions on governments’ use of the notwithstanding clause.

If accepted by the Supreme Court, it would mark the first substantive limits on Section 33 of the Charter of Rights and Freedoms. The section shields government laws from court challenges over alleged violations of rights, such as freedom of religion.

The federal government’s proposed limits sparked outrage among some conservative premiers, whose provinces in recent years have deployed or considered using the notwithstanding clause. Ontario Premier Doug Ford described it as Mr. Carney’s worst decision.

On Tuesday, the conservative premiers of Quebec, Ontario, Alberta, Saskatchewan and Nova Scotia put their complaints into writing, dispatching a letter to Mr. Carney.

Opinion: It’s not about the notwithstanding clause – it’s about the Charter

They said Ottawa’s proposal at the Supreme Court threatens national unity by seeking to undermine provincial sovereignty. In an unusual move, the premiers called on the federal government to “withdraw its written legal argument immediately.”

The federal Liberal argument was tabled as part of the Supreme Court case on Quebec’s Bill 21, the province’s secularism law. The 2019 legislation invoked the notwithstanding clause and disallowed public-sector workers, including teachers, from wearing religious symbols such as a hijab on the job.

In their letter on Tuesday, the five premiers wrote: “Regardless of our positions on the content of Bill 21, we support the constitutional right of any provincial legislature to invoke the notwithstanding clause.”

Bill 21 has been hotly political from the start in Quebec, and the debate shifted to the national stage last year, as an appeal process began at the Supreme Court. Since then, Quebec has continually said its autonomy is under attack.

Ottawa’s proposed restrictions on the notwithstanding clause – which, if accepted by the Supreme Court, would apply to the provinces and the federal government – intensified the political debate. The provinces on Tuesday said it was a “direct attack on the foundational constitutional principles of federalism and democracy.”

Opinion: If the notwithstanding clause is the nuclear option, Ottawa should respond proportionately

The federal Liberals made two proposals to the top court.

First, Ottawa argued courts should be able to declare rights have been violated, even if the notwithstanding clause means a law cannot be struck down.

Second, and more controversially, Ottawa wants the Supreme Court to establish a process for judicial review of longer-term use of the clause, arguing that prolonged use that prevents people from exercising rights is equivalent to denying those rights.

The federal proposal did not detail how that might work. The provinces on Tuesday said it constitutes “an unclear and unworkable legal standard with no basis in the text of the Constitution.”

The Prime Minister’s Office and Justice Minister Sean Fraser’s office did not respond to requests for comment on Tuesday afternoon.

Public opinion on governments’ use of the notwithstanding clause is sharply divided.

Opinion: It’s official: The Supreme Court’s ruling on Bill 21 will be one for the ages

In a Nanos Research poll conducted for The Globe and Mail, 33 per cent of Canadians said governments should be able to use the clause once to override a right, for the five-year period the Charter outlines; 32 per cent of people said it shouldn’t ever be used; 21 per cent support unlimited use; and 15 per cent were unsure.

Support for unlimited use was highest in Quebec, at 33.5 per cent. Opposition to any use was highest in Ontario, at 36.5 per cent.

The Nanos poll surveyed 1,052 people between Sept. 29 and Oct. 1. The results are considered accurate to within three percentage points, 19 times out of 20.

After Quebec’s Bill 21 became law in 2019, it was twice upheld in the lower courts as the provincial government defeated legal challenges. The Supreme Court agreed to hear an appeal last January. A hearing has not yet been scheduled but most of the legal arguments have been filed.