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Winter 2007


On November 29, 2006, the Supreme Court heard oral arguments in Massachusetts v. Environmental Protection Agency, the decision of which may have major implications for the regulation of carbon dioxide (“CO2”) and other greenhouse gases (“GHGs”). The case addresses whether the Environmental Protection Agency (“EPA”) has statutory authority under the Clean Air Act (“CAA”) to regulate CO2 and other GHGs emitted by new motor vehicles, and if it does, whether such authority is mandatory or discretionary. The case was brought by twelve states, three cities, an American territory, and various environmental organizations. Although the Court is unlikely to take a stand on the scientific legitimacy of climate change, its decision will have important implications for future climate-related claims, specifically regarding standing and regulatory issues.