U.S. Supreme Court Rules That EPA Can Regulate Auto Emissions

The U.S. Supreme Court has held that the Environmental Protection Agency (EPA) must regulate the greenhouse gas (GHG) emissions from new motor vehicles or provide a reasonable explanation for its failure to do so. The recently decided landmark case of Massachusetts v. Environmental Protection Agency initially began as a rulemaking petition brought by 19 private organizations, which were joined on appeal by the states of Massachusetts, California and New York, among others. On April 2, 2007, the Supreme Court decided the case in favor of these petitioners, acknowledging the relationship between rising global temperatures and increasing concentrations of atmospheric carbon dioxide and ruling that the Clean Air Act allows EPA to regulate GHG emissions from new motor vehicles.