In the Toolkit --


  • Guide to the Toolkit
  • Leagues in Action
  • I. Choosing a Role for Your League

    II. Grassroots Action Priorities

  • Climate Action
  • Price on Carbon
  • Our Children's Trust
  • Energy Efficient Buildings
  • Renewable Energy
  • Adapting to Climate Change
  • III. Basics of Climate Change

    IV. Engaging Individuals

  • Communicating About Climate Change
  • Preparing for a Meeting on Climate Change
  • Engaging Groups in Your Community
  • V. Promoting Public Policy

  • Community Action Models
  • Organizing For Community Action
  • Tips for Building Grassroots Support
  • League Action on Climate Change
  • International Action
  • VI. Resources

    Massachusetts v. EPA

    In a 5-4 decision in April 2007, the U.S. Supreme Court ruled that carbon dioxide (CO2) and other greenhouse gases (GHGs) meet the definition of "air pollutants" under the Clean Air Act (CAA) and that the Environmental Protection Agency (EPA) has the authority to regulate them.

    Origins of the case. In 1998, the EPA's General Counsel took the position that the EPA has the authority to regulate CO2 as an air pollutant under the CAA. The following year, a coalition of public interest groups petitioned the EPA to set vehicle emission standards for CO2 and other GHGs, on the grounds that these gases are pollutants that endanger the public health and welfare and must therefore be regulated.

    In 2003, the EPA denied the petition and issued a new legal opinion that the EPA is barred from regulating GHGs under the CAA. The petitioners, now joined by Massachusetts and a number of other state and local governments, filed a lawsuit challenging this decision, and in 2005, the U.S. Court of Appeals for the District of Columbia Circuit voted 2-1 to let the EPA's decision stand. The next year the U.S. Supreme Court agreed to hear the case.

    Massachusetts v. EPA. The petitioners charged that human-influenced global climate change was causing adverse effects, such as sea-level rise, to the state of Massachusetts. They argued that the CAA clearly authorizes the EPA to regulate emissions of CO2 and other GHGs from motor vehicles. Moreover, they asserted, the CAA provides that the EPA "shall" regulate air pollutants that, in the agency's judgment, "may reasonably be anticipated to endanger public health or welfare."

    The Court's ruling addressed three issues --

    Standing. The EPA maintained that Massachusetts et al. did not have standing to bring suit. (Standing requires that the litigant demonstrate that it has suffered an injury, that the injury is traceable to the defendant, and that it is likely that a favorable decision will redress the injury.)

    The Court found that the petitioners did indeed have standing to challenge the EPA's refusal to regulate vehicle emissions, reasoning as follows --

    Authority. The EPA argued that it lacked authority to regulate vehicle emissions because CO2 is not an air pollutant as defined by the CAA. The agency also claimed that it cannot regulate vehicle emissions because doing so would require it to regulate fuel economy standards, a job that Congress has assigned to the Department of Transportation (DOT).

    The Court rejected the EPA's arguments, finding --

    Discretion. The EPA further argued that, even if it did have authority to regulate GHGs, it would be unwise to do so at this time because (1) the administration was already responding effectively to the threat of global climate change, (2) regulating GHGs might impair the President's ability to persuade key developing nations to reduce emissions, and (3) reducing vehicle emissions would be an inefficient, piecemeal approach to addressing climate change.

    The Court disagreed, finding --