Ontario has asked the Supreme Court to weigh in on a historic youth-led challenge of the province’s climate plan, moving the case a step closer to a possible hearing before Canada’s top court.
While the court only hears a fraction of the cases it’s asked to review, lawyers for Ontario say this case strikes at an unresolved issue of national concern, The Canadian Press reports.
“This proposed appeal would ask this Court to determine, for the first time, whether and to what extent the Canadian Charter of Rights and Freedoms imposes obligations on Canadian governments to combat climate change,” read Ontario’s application for leave to appeal.
The case, Mathur v. Ontario, was brought by seven young people who argue Ontario’s weakened emissions target violated their rights under the Charter of Rights and Freedoms. In October, the Ontario Court of appeal breathed new life into the case by ordering a new hearing after a trial judge rejected it.
“This decision is a game-changer,” said Stewart Elgie, a specialist in environmental and natural resou rces law at the University of Ottawa, said at the time. “This is the strongest decision ever in Canada about a constitutional obligation to address climate change.”
The youth say the provincial the target violated their right to life in part by committing Ontario to dangerously high levels of planet-warming emissions and discriminated against them as youth who will bear the brunt of the impacts, CP says.
Fraser Thomson, a lawyer representing the young people, said Ontario’s application “opens the door to a generation-defining hearing before Canada’s highest court.”
“The climate crisis isn’t going away, and neither are we,” Thomson, environmental law charity Ecojustice’s climate director, said in a written statement.
The case dates back to when Premier Doug Ford’s then-newly elected Progressive Conservative government repealed the law underpinning Ontario’s carbon cap-and-trade system for lowering emissions.
The government scrapped the system in 2018 and replaced the emissions target in that law—37% below 1990 levels by 2030—with a new target of 30% below 2005 levels.
The seven youth contended the revised target allows for additional annual emissions equivalent to about seven million passenger vehicles.
They successfully defended attempts by Ontario to have the case tossed out, making it the first to be tried in Canada that considered whether a government’s climate plan may violate the Charter.
In a decision last year, an Ontario Superior Court justice agreed the gap between how much emissions need to be cut globally and what the provincial plan calls for is “large, unexplained, and without any apparent scientific basis.”
But the judge disagreed that the province’s emissions target amounted to a Charter violation. It wasn’t that the province’s target increased emissions, but that it allegedly did not do enough to reduce them.
The Court of Appeal for Ontario ruled that the case was not about whether the young people were trying to impose an obligation on the government to fight climate change, as the lower court judge suggested. Ontario had voluntarily chosen to fight climate change and the question was whether the target it chose complied with the Charter, the Appeal Court ruling said.
The case was sent back to the lower court for a new hearing. Ontario instead wants the Supreme Court to take it on.
“This case presents an excellent opportunity for Canada’s highest court to weigh in on the constitutional obligations of state actors in combating climate change – a recognized issue of national concern in
Canada,” lawyers for Ontario wrote in the application to the Supreme Court.
The case is being closely watched by lawyers in other climate cases across Canada.
An eight-week trial has been scheduled for October, 2026 [pdf] in a case where a group of young people are challenging the federal government’s climate plan.
The Supreme Court receives as many as 600 applications for leave to appeal every year and grants around 80, according to its website.
This report by The Canadian Press was first published Dec. 23, 2024.
