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On October 2025, a group of young Canadians sued the Canada Pension Plan Investments alleging the pension fund is mismanaging climate-related financial risks and failing to disclose and properly manage exposure to fossil fuel assets, thereby subjecting pension contributions to undue risk of loss from poorly managed climate risk. The complaint focuses on inadequate climate modeling/disclosure and fiduciary breaches. 

On September 4, 2020, an Ontario court struck down legislation requiring gas pumps to post notices informing customers that Canada's carbon pricing scheme will "cost" them.

In 2018 Canada enacted the Greenhouse Gas Pollution Pricing Act, which imposed a nationwide price on carbon. In May 2019, the Ontario Legislature enacted the Federal Carbon Tax Transparency Act, which required that a notice explaining certain fuel charges be posted on every gas pump in every gas station in Ontario. The notice stated "the federal carbon tax will cost you," with a graph showing costs to consumers rising through 2022. Corporation of the Canadian Civil Liberties Association (CCLA) brought suit seeking a declaration that the legislation violated the Canadian Charter of Rights and Freedoms.

The Court concluded that CCLA had public interest standing to bring the action, particularly because the group had tried to find a gas retailer to act as a co-plaintiff. The Court then concluded that the required notice adversely affected expression. Moreover, the Court reasoned, the notice was "inaccurate in a way that the Ontario government well knows" because the carbon pricing act serves a regulatory rather than a revenue-raising purpose, and so it is not a tax. Finally, the Court held that the notice's infringement on free speech was not justified because it served more to advance a partisan message than to share information with the public. The Court ordered the gas retailers may but do not need to keep the notices on their fuel pumps.

The Cap and Trade Cancellation Act (CTCA) was enacted by the province of Ontario in 2018. It repealed the Climate Change Mitigation and Low-Carbon Economy Act, which had established an emission reduction target of 37% below 2005 levels by 2030 in the province, and implemented a revised target of 30% below 2005 levels by 2030. In response, Ecojustice assisted seven youth environmental activists who filed an application against Ontario, contesting the constitutionality of CTCA. The Applicants argued that the revised target did not adequately address the risks associated with climate change, thereby violating the rights of Ontario youth and future generations as protected by sections 7 and 15 of the Canadian Charter of Rights and Freedoms. They contended that their section 7 right to life, liberty, and security of the person was infringed due to the perilous and existential threats posed by climate change to the lives and well-being of Ontarians. The Applicants maintained that their section 15 right to equality was violated because the revised target created a distinction based on age, imposing a greater burden on younger Ontarians who would endure the long-term impacts of climate change. They sought a declaration that the revised target was unconstitutional and an order requiring Ontario to establish a revised emissions target grounded in scientific principles, consistent with Ontario’s commitments under the Paris Agreement.

On April 15, 2020, Ontario filed a motion seeking to dismiss the case on the grounds that the claim was not justiciable. Ontario argued that determining emissions reductions was inherently political and thus unsuitable for judicial review. On November 12, 2020, Justice Brown of the Ontario Superior Court denied the motion, finding that it was not immediately apparent that the revised target would be immune from court scrutiny. 

In September 2022, the lawsuit proceeded to a hearing on its merits before the Ontario Superior Court. On April 14, 2023, Justice Vermette of the Ontario Superior Court determined that while the Applicants’ claim was justiciable, there was no violation of the Applicants’ sections 7 and 15 Charter rights. Regarding section 7 of the Charter, Justice Vermette found that the province’s revised target for reducing greenhouse gas (GHG) emissions was not arbitrary, as it was linked to the objective of GHG reduction under the CTCA. With respect to section 15 of the Charter, Justice Vermette concluded that the provision did not impose a positive obligation on the provincial government to take any specific actions to combat climate change. The Ontario Superior Court, therefore, dismissed the case. 

The applicants appealed to the Court of Appeal for Ontario in May 2023. On October 17, 2024, the Court of Appeal for Ontario released its decision unanimously in favor of the appeal. The Court found that the applicants’ case was not a positive rights case but rather a negative rights case because they were not requesting that Ontario implement specific climate change actions. Instead, they contended that the greenhouse gas emissions targets set by the Minister under the CTCA violated their Charter rights. In other words, by enacting the CTCA, the Ontario government voluntarily assumed a positive statutory obligation to combat climate change in a way that complies with the Charter. Given the lack of a complete evidentiary record, the ONCA declined to determine the applicants’ case on its merits and remitted the application for further consideration by the lower court.

On December 16, 2024, the Ontario government filed an application for leave to appeal the case to the Supreme Court of Canada. On May 1, 2025, the Supreme Court rejected the appeal. The case will now return to the Ontario Superior Court of Justice for a new trial. 

On October 11, 2019, the Superior Court of Ontario dismissed Greenpeace's case on the grounds that declaratory relief was not available. Two of the three judges reasoned that declaratory relief would have no practical effect because the statute that gave authority for the regulation at issue had been repealed. Had declaratory relief been able to have practical effect, two of the judges would have found that the Ontario government was required to participate in public participation before enacting the cancelling regulation.

Prior to the dismissal, on January 25, 2019, the court rejected a motion to dismiss on the grounds that the dispute was moot, reasoning that there was still a live dispute over whether the public participation in question was lawful. 

Environmental groups filed suit against the Ontarian government, alleging the government failed to meet legal requirements for public consultation on regulations that would end Ontario’s cap and trade program and a proposed bill that would undercut the province’s legislative regime for combatting climate change. Plaintiffs argued that both the regulations and bill violate requirements under the Environmental Bill of Rights (EBR) for public participation in the development of environmentally significant regulations and legislation. 

The lawsuit concerns Ontario Regulation 386/18 filed on July 3, 2018 by the Minister of Environment, Conservation and Parks. The government did not conduct a public consultation process and filed a claim that the 2018 election was “substantially equivalent” to the 30-day consultation process required by law. Plaintiffs argued that the government was still required to undertake public consultation for the regulation under the EBR and that the regulation is ultra vires because it contradicts the purpose of the “Climate Change Mitigation and Low-Carbon Economy Act,” the enabling act for this regulation. The lawsuit additionally concerned “Bill 4, the Cap and Trade Cancellation Act, 2018” filed on July 25, 2018. This bill would repeal the “Climate Change Mitigation and Low-carbon Economy Act, 2016” which includes greenhouse gas emission reduction targets. Plaintiffs argued that this bill would have a significant environmental impact because it would repeal existing greenhouse gas emissions targets without establishing new targets. If there is a significant environmental impact, then the government must undertake the mandatory notice and comment process required by the EBR. 

Plaintiffs sought declaratory relief and asked the Court to quash the regulations.


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