One year after the world’s highest court ruled that countries have a legal duty to fight climate change, Canada’s federal and provincial governments are expanding fossil fuels anyway, a move that could leave them legally exposed.

The ICJ landmark opinion on July 23, 2025 found that the production and consumption of fossil fuels “may constitute an internationally wrongful act attributable to that state.”

The opinion is not legally binding, but carries weight: it holds that the 1.5°C Paris Agreement temperature target, to which Canada is a signatory, is legally binding. It also stipulates that all states, in particular the largest emitters, “must take ambitious mitigation measures in line with the best available science.”

Andrew Gage, staff lawyer with West Coast Environmental Law (WCEL), told The Energy Mix this could leave Canada liable within the ICJ’s jurisdiction—which is state behaviour toward other states.

If another country believes it has been directly harmed by Canada’s failure to meet its climate obligation, it could present a case in international court.

Domestically, the ICJ opinion and its potential for liability are more ambiguous, but Gage argues it could inform a finding of liability in several different ways.

“The ICJ opinion makes it very clear that state actions in relation to climate change can amount to human rights violations,” Gage told The Mix in a phone interview. “Many of those…are human rights that are protected under Canadian law directly.”

“[It] becomes very relevant for understanding what Canada and, for that matter, provincial governments are responsible for under Canadian law,” Gage said. 

Although the opinion is not binding, he added, a Canadian court or human rights commission would look at it while interpreting Canadian or provincial law.

Across the country, provincial and federal governments are moving forward with fossil fuel expansion in contradiction of the ICJ opinion. Newfoundland and Labrador is pushing forward with offshore drilling despite a 2018 oil spill that shut down operations at the time.

The Alberta and federal governments are also moving forward with plans to develop an oil pipeline from the Alberta oil sands to British Columbia tidewater.

Meanwhile, the ICJ opinion is entering climate court cases in Canada. WCEL is providing support to a case filed by youth against the Canadian government for its role in causing climate change.

That case was filed years ago, well before the newly-proposed pipeline. But Gage says the pipeline and rollbacks of environmental laws will be put before the court when it goes to trial in October, and the ICJ decision will likely be referenced by the lawyer arguing that case.

Another case, filed by Ecojustice on behalf of three youth, the Canadian Association of Physicians for the Environment, and Environmental Defence Canada, also cites the ICJ decision. Their case focuses on whether the government is complying with the Canadian Net-Zero Emissions Accountability Act.

“That’s not a constitutional case, that’s purely an interpretation of that statute case, but nonetheless the ICJ decision is relevant for understanding these obligations,” said Gage.

“All of which is to say, absolutely, the liability of Canada or the provinces under Canadian law can be that the courts often look to international agreements, international jurisprudence, and customary international law to understand and interpret the obligations of governments under Canadian law.”