Supreme Court Ruling: EPA vs. MA

Supreme Court Decision in
Massachusetts et al vs. Environmental Protection Agency

On April 2, 2007 the Supreme Court released its ruling in the case of the state of Massachusetts vs. the Environmental Protection Agency. Massachusetts and eleven other states, along with several local governments and non-governmental organizations (petitioners), sued the EPA for not regulating the emissions of four greenhouse gases, including carbon dioxide (CO₂), from the transportation sector. The petitioners claimed that human-influenced global climate change was causing adverse effects, such as sea-level rise, to the state of Massachusetts. In a 5-4 decision, the court ruled in favor of Massachusetts et al, finding that EPA has the authority to regulate CO₂ and other greenhouse gases. The decision was written by Justice Stevens and was signed by Justices Kennedy, Souter, Bader Ginsburg, and Breyer. Chief Justice Roberts and Justices Alito, Scalia, and Thomas dissented. The Court’s findings are summarized below:

Standing

The EPA argued that Massachusetts et al could not prove standing in this case. The Court ruled that Massachusetts et al do in fact have standing in challenging EPA’s decision not to regulate CO₂ and other greenhouse gases from the transportation sector. Standing requires injury, causation, and the existence for a remedy. The Court found that EPA’s refusal to regulate CO₂ has led to “actual” and “imminent” harm to the state of Massachusetts, mainly in the form of rising sea-levels along the state’s coast. The ruling also noted that “the harms associated with climate change are serious and well recognized.” The Court also found that “given EPA’s failure to dispute the existence of a causal connection between man-made greenhouse gas emissions and global warming, its refusal to regulate such emissions, at a minimum, contributes to Massachusetts’ injuries.” Finally, while acknowledging that regulating greenhouse gases from motor vehicles alone will not reverse global warming, the Court found that domestic action such as this can play a role in slowing or reducing warming.

EPA Has Authority to Regulate Greenhouse Gases

The EPA argued that it was not given the authority under the Clean Air Act to regulate CO₂ or other greenhouse gases. The Court challenged the EPA’s refusal to regulate CO₂ as an air pollutant under the statute. The Court found that CO₂ fits within the statute’s broad definition of an air pollutant. Further, the Court stated that “EPA identifies nothing suggesting that Congress meant to curtail EPA’s power to treat greenhouse gases as air pollutants.” In its case, the EPA argued that regulating CO₂ would require regulating fuel economy standards, which – according to the EPA – is under the purview of the Department of Transportation. The Court countered the EPA by recognizing that multi-agency efforts can indeed overlap when addressing an issue as important as global climate change: “The fact that DOT’s mandate to promote energy efficiency by setting mileage standards may overlap with EPA’s environmental responsibilities in no way licenses EPA to shirk its duty to protect the public health and welfare.” Protecting public health and welfare is a duty mandated by the Clean Air Act.

EPA Must Protect Public Health and Welfare

Finally, EPA argued that even if it was granted authority to regulate greenhouse gases under the Clean Air Act, it would be “unwise to do so at this time,” stating that it might conflict with the current administration’s effort to address climate change, particularly with regard to international climate negotiations. The Court found EPA’s argument that regulating emissions from the transportation sector “might hamper the President’s ability to persuade key developing nations to reduce emissions” to be insufficient. Rather, according to the Court, “A reduction in domestic emissions would slow the pace of global emissions increases, no matter what happens elsewhere.” Further, the Court ruled that “under the Act’s clear terms, EPA can avoid promulgating regulations only if it determines that greenhouse gases do not contribute to climate change or if it provides some reasonable explanation as to why it cannot or will not exercise its discretion to determine whether they do.” Finally, the Court found unreasonable EPA’s argument that regulation of CO₂ in the transportation sector would not make significant reductions in emissions, noting that although enforcing regulations may not by itself reverse global warming, it is the duty of EPA to take such a step in order to “slow or reduce” global warming.

This opinion is important for national and local climate change policy. Not only does it open the door to regulation of greenhouse gases under the Clean Air Act, but is also likely to catalyze calls for more comprehensive federal climate change legislation (pdf) – legislation that covers sectors other than transportation as well as non-CO₂ greenhouse gases. This ruling could lend support for state efforts such as the California legislation intended to regulate greenhouse gases as a pollutant in the transportation sector. In turn, expanded state activity will likely build even more pressure for a more uniform federal program.

Read more about GHG emissions standards in the transportation sector.

Read the complete Ruling (pdf).