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An Elections Ontario voting sign outside a polling station at Westmount Junior School in Etobicoke, Ont., on Feb. 27.Laura Proctor/The Canadian Press

Canada’s Supreme Court has struck down a section of Ontario’s elections finance law that restricts the amount third parties can spend in the year before a provincial election period, saying the measure compromises voting rights.

Friday’s 5-4 ruling found the section of the Ontario Election Finances Act in question violates the right to vote enshrined in the Charter of Rights and Freedoms.

Writing for herself and four other members of the nine-member court, Justice Andromache Karakatsanis endorsed the value of third-party advertising in the political process.

“Third-party advertising assists citizens casting an informed vote as third parties encompass a diverse range of citizens and groups who aim to provide information to other citizens, and draw attention to issues of importance to them,” she wrote.

“Limits that restrict rather than promote citizens’ access to diverse information and views may violate their right to meaningfully participate in the political process.”

In response to Friday’s ruling, Grace Lee, a spokesperson for Ontario Premier Doug Ford, said the court’s decision has no immediate impact, given that it comes after the recent provincial election in which Mr. Ford and his government won a strong mandate.

“We’ll review the decision and determine next steps in due course,” said Ms. Lee.

At issue was the section of 2021 Ontario legislation that limited spending on third-party advertising to $24,000 in any one electoral district and to $600,000 in total during the year before an election.

Ontario’s Progressive Conservative government said the measure was necessary to shield elections from outside influence, but critics raised concerns about the government trying to fend off detractors ahead of a 2022 election in which the Conservatives won a majority.

In 2021, the Ontario government invoked the Constitution’s notwithstanding clause and overrode a recent court ruling against the legislation. The clause allows a government to temporarily override some rights.

When the law had first been put into place, it was challenged by several third-party groups, including the Working Families Coalition and teachers’ unions. A lower court struck it down on free speech grounds.

The province responded by tabling a new version of the bill that used the notwithstanding clause, a provision under the Charter that allows a government to temporarily override some rights.

In its own ruling, the Ontario Court of Appeal struck down the section in dispute, but suspended the action for a year. The Ontario government appealed that court’s decision, leading to Friday’s ruling.

In the Supreme Court of Canada ruling, Justice Karakatsanis wrote that the controversial section of the provincial legislation – 37.10.1 (2) – “has the clear potential to severely curtail voters’ exposure to different views on the political issues that define their community in the year before the election period.”

Four members of the court, including Chief Justice Richard Wagner, issued dissenting opinions indicating they would have allowed the appeal at hand.

Lawyer Paul Cavalluzzo, who represented the Working Families Coalition and the Ontario English Catholic Teachers’ Association in the case, said Friday that the ruling would have a national impact.

He said in an interview that the ruling was framed in such a way that it gives a very good framework for how the Charter section on voting rights should be interpreted in the context of the Ontario legislation.

But he noted that the impact may be felt outside the province. “It will be a good guide to every jurisdiction in Canada,” he said.

“Why it matters is the court is very clear that when governments pass legislation relating to elections, the courts will very carefully scrutinize what they have passed because the government can pass legislation, which advantages itself and which is to the detriment of the government’s opponents,” he said.

Mr. Cavalluzzo said he hoped the government, in response, would pass legislation which is Charter compliant.

Kristyn Wong-Tam, the provincial NDP critic for the attorney general, said in a statement that Mr. Ford had wasted taxpayers’ dollars fighting to silence critics and defending unconstitutional laws.

“Ontarians deserve a healthy democracy where they can cast an informed ballot,” said Ms. Wong-Tam. “This defeat should be a wake-up call for Ford.”

Teachers’ groups involved in the action against the election law said in a joint statement that the Supreme Court ruling shows no government is above the law.

“This decision is a win for all Ontarians who value their Charter-protected rights and the health of our democracy,” said the statement issued by the Elementary Teachers’ Federation of Ontario, the Ontario English Catholic Teachers’ Association and the Ontario Secondary School Teachers’ Federation.

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