WASHINGTON, D.C. — The case involves a lawsuit filed by the city and county of Boulder, Colorado, against Suncor Energy and Exxon Mobil. Boulder filed the lawsuit in Colorado state court in 2018. Boulder alleges that Exxon Mobil and Suncor engaged in unchecked production, promotion, refining, marketing, and sale of fossil fuels. The complaint further alleges that the companies concealed or misrepresented the dangers associated with fossil fuels' intended use.

Boulder alleges that these actions led to a rise in greenhouse gas concentrations, causing atmospheric and ocean warming, extreme heat, wildfires, and ecosystem changes. Boulder is seeking billions of dollars in damages for property damage, mitigation measures, repairs, emergency services, and public-health measures. Exxon Mobil and Suncor argued that the Clean Air Act and the Constitution prevent Boulder's claims from proceeding under state law. Exxon Mobil is the nation's largest oil company.

Suncor Energy operates two refineries in Colorado, which are located in the Denver metropolitan area. One of these facilities is the Trinidad Refinery in Las Animas County. Suncor Energy Inc is a Canadian energy company.

The Colorado Supreme Court allowed Boulder's case to proceed in May 2025. The ruling rejected the companies' argument that federal law preempts the claims. The U.S. Supreme Court granted review of the Colorado Supreme Court's decision in February 2026. Boulder’s lawsuit against Suncor and ExxonMobil has been pending for years, with the Colorado Supreme Court allowing it to proceed after procedural delays and appeals.

Alexandra Nagy, organizing director of Consumer Watchdog, said: "Justice Alito’s recusal from Suncor v. Boulder is the right decision, and one he should have made from the start." Exxon Mobil has been involved in multiple climate change lawsuits across the U.S. including cases in California, New York, and Washington state.

Why It Matters

The recusal occurs just days before the Supreme Court is set to hear oral arguments in a case that could determine whether state courts can adjudicate climate damages against major energy producers. The lawsuit seeks billions in damages for alleged environmental harms, and its outcome may influence similar litigation nationwide. The Supreme Court’s 2023 Code of Conduct establishes standards for recusal when impartiality might reasonably be questioned due to financial interests.

Justice Alito’s financial disclosures show holdings in oil companies other than the defendants, yet those firms have also faced climate litigation risks. Consumer Watchdog noted that such risks were disclosed to shareholders, raising questions about potential conflicts under the code of conduct. A Supreme Court spokeswoman previously stated that Alito had no financial interest in the parties and that recusal was not required, but the justice ultimately stepped away from the case without providing a public reason.

Timeline

On September 28, 2026, Supreme Court Justice Samuel Alito will not continue to participate in the case Suncor Energy Inc. v. County Commissioners of Boulder County. On that same date, the letter stated: "Justice Alito has determined that he will not continue to participate in this case." Also on September 28, 2026, Scott Harris, the clerk of the Supreme Court, signed a letter informing lawyers in the dispute that Alito would not continue to participate. The letter did not provide a reason for Alito's recusal.

What's New

Nagy, organizing director of Consumer Watchdog, said: "Justice Alito’s recusal from Suncor v. Boulder is the right decision, and one he should have made from the start." In 2025, Justice Alito disclosed financial holdings in ConocoPhillips and Phillips 66, two oil companies that have also faced climate-related lawsuits, according to his annual financial disclosure report. Consumer Watchdog’s 2026 report stated that ConocoPhillips and Phillips 66 explicitly warned shareholders in annual disclosures about climate litigation risks, aligning with the Supreme Court’s 2023 code of conduct requirements for recusal. In May 2026, a Supreme Court spokeswoman stated that Alito did not have a financial interest in any party involved in the case and that his recusal was not required.