The U.S. Supreme Court is set to hear arguments in its upcoming term on a climate change lawsuit brought by Boulder County and the city of Boulder against major oil companies Suncor Energy and Exxon Mobil. The case, Suncor Energy v. Boulder County, raises the question of whether state and local governments can hold corporations liable under state tort laws for contributing to global climate change.
Boulder County and the city of Boulder filed their lawsuit in Colorado, alleging that the fossil fuel companies’ worldwide production and sale of petroleum products have caused harm to their community through climate-related impacts. They seek monetary damages for these local harms, asserting that oil companies should be accountable for their share of global greenhouse gas emissions. The case could allow a jury at the local level to determine the extent of responsibility each company has for climate change on a global scale.
The litigation is part of a broader trend of lawsuits initiated by left-leaning states and municipalities aimed at challenging fossil fuel companies through the courts. However, the defendants argue the case raises significant constitutional issues. Key legal objections include the principle that one state’s laws cannot regulate matters that cross state and national borders, and the doctrine of extraterritoriality, which limits states from applying their laws to conduct outside their jurisdiction.
Moreover, defendants contend that federal law, particularly the Clean Air Act, assigns primary authority for regulating greenhouse gas emissions to the Environmental Protection Agency (EPA), with states having only limited control over local sources. Beyond these statutory and jurisdictional arguments, the case also implicates U.S. foreign policy—a domain constitutionally reserved to the federal government.
The complaint’s focus on the global nature of climate change, including the attribution of responsibility among American, foreign companies, and foreign countries, involves foreign relations issues. The Constitution grants the federal government exclusive authority over foreign affairs to ensure that the United States speaks with a unified voice internationally and that diplomatic negotiations and policy decisions remain coherent.
Legal experts point out that allowing local jurisdictions to impose liability based on global emissions could fragment national policy and disrupt the federal government’s ability to manage international climate agreements and trade-offs involving environmental, economic, and security considerations. They warn that if Boulder’s approach is upheld, it could lead to numerous states and municipalities imposing varying liability standards on companies, potentially resulting in staggering cumulative financial exposure estimated in the trillions of dollars, while foreign emitters remain beyond the reach of American courts.
Previous Supreme Court rulings have held that states may regulate traditional local matters even if such regulations have incidental foreign relations effects. However, courts have consistently struck down attempts by states to intrude directly on foreign policy without a legitimate local interest. Boulder’s suit, critics contend, does not represent a traditional state regulatory role but instead challenges the federal government’s exclusive competence over international engagement.
The Supreme Court’s review of Suncor Energy v. Boulder County will address these foundational questions about the balance of state and federal authority over climate change regulation and the role of the judiciary in resolving complex environmental and foreign policy disputes. The outcome could define limits on how far local governments may go in pursuing climate litigation against energy companies within a global context.