549 U.S. 497 (2007)
The EPA argued that the Clean Air Act (CAA) did not authorize the EPA to address global climate change and that, in any event, executive policy specifically addressing global warming warranted the EPA's refusal to regulate in such area.
- The U.S. Supreme Court first held that petitioners had standing to challenge EPA's denial of their rulemaking petition since at least one petitioner state properly asserted a concrete injury from the potential further loss of its coastal land, much of which was owned by the state, from rising sea levels caused by climate change.
- Further, because greenhouse gases were clearly within the CAA's broad definition of an air pollutant, the EPA had the statutory authority to regulate the emission of such gases from new motor vehicles, and there was no showing of any congressional intent to bar the EPA from addressing global warming.
- Also, it was undisputed that global warming threatened serious harms, and policy considerations were irrelevant to the EPA's statutory mandate to determine whether the greenhouse gases contributed to global warming and whether motor vehicle emissions of such gases actually or potentially endangered public health or welfare.
The judgment upholding EPA's determination to decline rulemaking was reversed, and the case was remanded for further proceedings.