On Monday, the U.S. Supreme Court hears oral arguments in Suncor Energy v. Boulder, a climate change lawsuit where local Colorado governments are seeking billions in damages from major energy companies. The case tests whether state tort claims over global greenhouse gas emissions are preempted by federal law, pitting fossil fuel producers against municipal plaintiffs.
The Boulder Lawsuit and the Fight Over State Court Jurisdiction
The legal battle began in 2018 when the City and County of Boulder filed suit in state court against energy giants Suncor Energy and ExxonMobil. According to Mother Jones, plaintiffs are demanding compensation for local expenses tied to extreme weather, including burned cattle, drought conditions, and severe wildfires like the one that devastated Rio Blanco County in 2025. Boulder argues that these companies not only contributed to rising temperatures but actively misled the public about the environmental risks of fossil fuels.
Energy producers have consistently tried to kill the litigation before it reaches trial. The defendants contend that regulating global climate change falls exclusively under federal purview because greenhouse gas emissions cross state boundaries. Suncor and Exxon argue that permitting individual municipal jurisdictions to impose liability based on worldwide fuel sales would create a chaotic patchwork of punitive carbon taxes capable of bankrupting the domestic energy sector.
Justice Alito Recusal and the Judicial Spotlight on Clarence Thomas
The high-stakes arguments arrive with a depleted bench. Justice Samuel Alito recused himself from the case. While Alito does not own shares in Suncor or ExxonMobil, his disclosures reveal investments in other energy firms such as ConocoPhillips and Phillips 66. Watchdog groups praised the step-aside under the court’s judicial ethics code, leaving eight justices to decide the appeal.
Attention has shifted sharply toward Justice Clarence Thomas and Justice Neil Gorsuch. Environmental advocates and energy lawyers alike are scrutinizing Thomas’s past opinions regarding federal preemption. Although Thomas has consistently sided against environmentalists on regulatory matters, he has frequently expressed skepticism toward letting federal authority override state laws when Congress has not explicitly stated its intent to do so.
| Party | Core Legal Position | Primary Legislative Basis |
|---|---|---|
| Boulder County & City of Boulder | State tort law allows recovery for local adaptation costs and deception regarding climate risks. | State-level property and consumer protection laws |
| Suncor Energy & ExxonMobil | Interstate pollution and global climate policy are exclusively governed by federal law. | Clean Air Act and federal preemption doctrine |
Broader Industry Implications and the Path Forward
The Supreme Court agreed in February to hear the oil companies’ appeal after the Colorado Supreme Court rejected their preemption arguments. The fossil fuel industry views this appeal as a crucial opportunity to secure near-blanket immunity from widespread public nuisance and damages lawsuits, paralleling historic litigation against tobacco and opioid manufacturers. Dozens of similar climate-related municipal lawsuits across the United States remain on hold, awaiting the high court’s definitive ruling on whether local courthouses remain open to climate damage claims.
