Washington: The US Supreme Court heard arguments on Monday over whether local governments can sue fossil fuel companies in state courts for costs linked to climate change, with the outcome potentially affecting dozens of cases across the US.
The case, Suncor Energy Inc. v. County Commissioners of Boulder County, stems from a 2018 lawsuit filed by Boulder city and county officials in Colorado against Suncor Energy and ExxonMobil. The local governments argue the companies should contribute towards costs associated with climate related impacts.
Boulder officials allege that Exxon and Suncor concealed or misrepresented what they knew about the climate effects of burning fossil fuels. The companies dispute the lawsuit's legal basis and argue that federal law bars such claims under state law.
The dispute centres partly on whether the federal Clean Air Act and other principles of federal law preempt state level climate claims. The companies argue that climate change is a global issue involving emissions across state and national borders.
During arguments, several justices questioned how broadly such lawsuits could extend. Chief Justice John Roberts raised concerns that allowing Boulder’s case to proceed could lead municipalities across the country to file similar claims, while Justice Brett Kavanaugh questioned the potential scale of liability.
Other justices questioned whether federal law clearly prevents states from hearing the cases. Justice Elena Kagan drew comparisons with previous state litigation involving tobacco and opioid companies, while Roberts noted that state courts already handle cases involving conduct with effects beyond state borders.
The Supreme Court is also considering whether it should decide the dispute at this stage. The Colorado Supreme Court had allowed Boulder’s lawsuit to move towards trial, but the underlying case has not yet been completed.
Justice Samuel Alito recused himself, leaving eight justices to hear the arguments. His absence raises the possibility of a 4 4 split, which would leave the Colorado ruling in place without establishing a nationwide Supreme Court precedent.
The stakes extend beyond Colorado. A ruling favouring the oil companies could affect dozens of climate related lawsuits brought by state and local governments, while a ruling allowing Boulder’s case to proceed would permit its claims to continue in state court.
The Trump administration has sided with the oil companies in the dispute, while Boulder maintains that it is seeking compensation for alleged local damages rather than attempting to regulate greenhouse gas emissions nationally.
A Supreme Court ruling is expected next year.
