Massachusetts v. EPA Sets the Standard for Climate Lawsuits

With climate change lawsuits on the rise, environmentalists are concerned that the conservative-leaning Supreme Court may revisit a landmark environmental law decision. In Massachusetts v. EPA, 549 U.S. 497 (2007), the Court ruled by a vote of 5-4 that the Environmental Protection Agency (EPA) has the authority to regulate carbon dioxide under the Clean Air Act (CAA).

Facts of the Case

In section 202(a)(1) of the CAA, Congress directed the EPA to issue standards applicable to the emission of “air pollutants” from new motor vehicles, which in EPA’s “judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare…” The CAA defines “air pollutant” to include “any air pollution agent . . . , including any physical, chemical . . . substance . . . emitted into . . . the ambient air.”

In 1999, a group of private organizations petitioned the EPA to begin regulating the emissions of four such gases, including carbon dioxide. The EPA ultimately denied the petition, reasoning that (1) the Act does not authorize it to issue mandatory regulations to address global climate change, and (2) even if it had the authority to set greenhouse gas emission standards, it would have been unwise to do so at that time because a causal link between greenhouse gases and the increase in global surface air temperatures was not unequivocally established. The agency further characterized any EPA regulation of motor-vehicle emissions as a piecemeal approach to climate change that would conflict with the President’s comprehensive approach involving additional support for technological innovation, the creation of nonregulatory programs to encourage voluntary private-sector reductions in greenhouse gas emissions, and further research on climate change, and might hamper the President’s ability to persuade key developing nations to reduce emissions.

The State of Massachusetts, along with several other state and local governments, sought review in the D.C. Circuit Court of Appeals. In a fractured decision, the federal appeals court denied review.

Supreme Court’s Decision

The Supreme Court reversed. Justice John Paul Stephens wrote on behalf of the five-member majority.

The Court first addressed the issue of standing, concluding that Massachusetts had standing to challenge the EPA’s denial of their rulemaking petition. In reaching its decision, the Court emphasized that Massachusetts is a sovereign State — not private individual. Accordingly, it had a special position and interest in the case.

The majority went on to conclude that the “EPA’s steadfast refusal to regulate greenhouse gas emissions presents a risk of harm to Massachusetts that is both ‘actual’ and ‘imminent.’” It further found that there was a substantial likelihood that the judicial relief requested would prompt EPA to take steps to reduce that risk.

[T]he rise in sea levels associated with global warming has already harmed and will continue to harm Massachusetts,” Justice Stevens wrote. “The risk of catastrophic harm, though remote, is nevertheless real. That risk would be reduced to some extent if petitioners received the relief they seek.” Notably, the Court also held that while regulating motor-vehicle emissions may not by itself reverse global warming, that doesn’t mean that the Court lacks jurisdiction to decide whether EPA has a duty to take steps to slow or reduce it.

The Court next turned to the EPA’s authority under the CAA. It concluded that because greenhouse gases fit well within the Act’s capacious definition of “air pollutant,” EPA has statutory authority to regulate emission of such gases from new motor vehicles.

“While the Congresses that drafted §202(a)(1) might not have appreciated the possibility that burning fossil fuels could lead to global warming, they did understand that without regulatory flexibility, changing circumstances and scientific developments would soon render the Clean Air Act obsolete,” Justice Stevens wrote.

The majority rejected what it characterized as the EPA’s “laundry list of reasons not to regulate,” emphasizing that the EPA couldn’t avoid its obligations with “policy judgments … [that] have nothing to do with whether greenhouse gas emissions contribute to climate change.” Justice Stevens further explained:

Nor can EPA avoid its statutory obligation by noting the uncertainty surrounding various features of climate change and concluding that it would therefore be better not to regulate at this time. See 68 Fed. Reg. 52930–52931. If the scientific uncertainty is so profound that it precludes EPA from making a reasoned judgment as to whether green- house gases contribute to global warming, EPA must say so.

The Court remanded the matter to EPA, leaving it up to the agency to determine whether greenhouse gases endanger public health or welfare.