Massachusetts v. Environmental Protection Agency Case Brief

Facts of the case

Massachusetts and several other states petitioned the Environmental Protection Agency (EPA), asking EPA to regulate emissions of carbon dioxide and other gases that contribute to global warming from new motor vehicles. Massachusetts argued that EPA was required to regulate these greenhouse gasesby the Clean Air Act – which states that Congress must regulate any air pollutantthat can reasonably be anticipated to endanger public health or welfare.EPA denied the petition, claiming that the Clean Air Act does not authorize the Agency to regulate greenhouse gas emissions. Even if it did, EPA argued, the Agency had discretion to defer a decision until more research could be done on the causes, extent and significance of climate change and the potential options for addressing it.Massachusetts appealed the denial of the petition to the Court of Appeals for the D.C. Circuit, and a divided panel ruled in favor of EPA.

Why is the case important?

&nbsp The State of Massachusetts is suing the Environmental Protection Agency (EPA) for denial of their rulemaking petition in connection to regulation of green-house gases.


Whether a State has standing to sue the EPA for not enforcing the Clean Air Act.


Yes. In order to have standing a petitioner must have injury, causation and redressability. Typically the injury of green-house gases would be too tenuous for an individual to claim is a direct injury. However this is the State that is filing suit not the individual. The State has a quasi-sovereign interest. The State has an interest in the land on its coast, and they have shown the injury of losing coastal property as the water rises. The State has also shown the casual connection, which the EPA does not deny, that global warming is a cause of the water rising. As for redressability, that is shown as well. If the EPA regulates emissions from cars, that will help the issue of global warming in the State of Massachusetts. Since all requirements are shown, standing is proper.


The U.S. Supreme Court 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.

  • Advocates: James R. Milkey argued the cause for Petitioners Gregory G. Garre argued the cause for Respondents
  • Petitioner: Massachusetts et al.
  • Respondent: Environmental Protection Agency et al.
  • DECIDED BY:Roberts Court
  • Location: –
Citation: 549 US 497 (2007)
Granted: Jun 26, 2006
Argued: Nov 29, 2006
Decided: Apr 2, 2007
Massachusetts v. Environmental Protection Agency Case Brief