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Ogmius Newsletter

Research Highlight

Massachusetts v. EPA: Who Should Run the Greenhouse?

Marilyn AverillMarilyn Averill is a doctoral student in Environmental Studies at the University of Colorado.  Her research interests focus on international environmental governance, the politics of science, and science and technology policy, particularly in the context of global climate change.  Marilyn formerly worked as an attorney with the Office of the Solicitor, United States Department of the Interior, where she provided legal advice to the U.S. Fish and Wildlife Service and the National Park Service.  She holds Master’s degrees in Public Administration from the Kennedy School of Government and in Educational Research and Evaluation Methodology from the University of Colorado, and a law degree from the University of Colorado.

Marilyn’s recent work has focused on the use of science and the treatment of uncertainty in litigation relating to climate change, and the effects these cases may have on law, science, and policy.  The following Research Highlight describes her assessment of the recent U.S. Supreme Court decision on EPA’s authority to regulate greenhouse gas emissions under the Clean Air Act.

In a split (5 to 4) decision in Massachusetts v. Environmental Protection Agency (EPA), 549 U.S. __ (2007), the Supreme Court ruled that the Clean Air Act (CAA) gives the EPA authority to regulate greenhouse gas (GHG) emissions from the tailpipes of new motor vehicles.  The Court sent the case back to EPA to decide whether such emissions “may reasonably be anticipated to endanger public health or welfare,” the CAA standard.

This case has little to do with climate science or even global warming and much to do with the role courts should play in deciding cases of social significance in a democratic society.  It is less about EPA’s authority than about the Court’s authority, and involves views of the separation of powers of the three branches of our government.  Climate science was generally uncontested.  None of the three opinions questions whether global warming is occurring or whether it is partly driven by human activities, but the justices strongly disagreed as to which branch of government should address the problem. 

Much of the majority opinion and the two dissenting opinions focus on whether the issue of regulating greenhouse gases is justiciable, that is, whether this case should be decided by the courts.  More specifically, the case is about whether plaintiffs had standing to bring their claims to the courts.  U.S. courts are limited to deciding cases and controversies grounded in specific allegations of injuries that can be redressed by a court’s decision.  The majority found that plaintiffs had adequately alleged injuries to support standing; the dissent disagreed.  The majority applied a relaxed standard for standing available only to states, so this case may not provide useful precedent for private litigants seeking to establish standing in other climate-related cases.

Uncertainty continues to play an important role.  The majority allowed standing, but left the door open for EPA to find that “scientific uncertainty is so profound” that EPA cannot determine whether GHGs endanger human health or welfare.  (Opinion at 31.)  For the dissent, uncertainty blurs the causal link between GHG emissions and the injuries alleged, as well as EPA’s ability to remedy the situation. 

This decision’s effects may be primarily symbolic.  EPA has avoided regulating GHGs for the last six years and probably will continue to do so until the current administration leaves office.  Regardless of content, future CAA regulation alone will do little to address the problem of global warming.  But effects may extend beyond regulation.  Congress has been considering proposals on climate change and debate over this case could stimulate action.  Congress now has several options. It can do nothing and let EPA reconsider its decision not to regulate GHGs; step in to limit or expand EPA’s authority under the CAA; or provide a more comprehensive framework for dealing with climate change issues at the federal level.  All of this will take time, so in spite of this decision, federal regulation of GHGs may not occur any time soon. 

Marilyn Averill
Center for Science and Technology Policy Research