AEP, the second case in which the Supreme Court has confronted the problem of climate change, builds from the Court’s decision four years earlier in Massachusetts v. EPA. But AEP also takes place in a broader context, in which numerous state and federal courts in this country and others, as well as international tribunals, face an increasing number of cases involving climate change. The vast majority of those cases are not common law nuisance cases like AEP, but rather regulatory actions interacting with local land use planning and with state and federal environmental law. In AEP, the Court shapes the path of climate change litigation by reinforcing the appropriateness of regulatory actions while limiting federal common law public nuisance ones. This commentary considers: (1) the framework for climate change litigation created by the combination of AEP and Massachusetts; (2) the pathways the Court endorses, shuts down, and leaves open; (3) the Court’s view of the limited role that courts, as opposed to the Environmental Protection Agency (EPA), should play in assessing climate change science under the current regulatory scheme; and (4) the benefits and limitations of the path forward from AEP.

The Court’s approach to climate change litigation in AEP flows from its analysis of both threshold and substantive issues in Massachusetts. The four-Justice plurality in AEP upheld Massachusetts’s rationale for finding standing,and Professor Daniel Farber’s commentary analyzes that issue in depth.Moreover, as Professor Jonathan Adler discusses, AEP bases its displacement decision on Massachusetts’s finding that greenhouse gas emissions qualify as air pollutants under the Clean Air Act. AEP interprets that finding as establishing Congress’s delegation to the EPA of “whether and how to regulate carbon-dioxide emissions from power plants; the delegation displaces federal common law.”

In the process of explaining its displacement holding, the Court in AEP made two interrelated points that will shape the possibilities for U.S. climate change litigation. It precluded federal common law nuisance actions as a mechanism for challenging the EPA’s approach to climate change regulation—even if the EPA declines to regulate—so long as the EPA has regulatory authority. At the same time, the Court reinforced the appropriateness of regulatory suits challenging the EPA: “If the plaintiffs in this case are dissatisfied with the outcome of EPA’s forthcoming rulemaking, their recourse under federal law is to seek Court of Appeals review, and, ultimately, to petition for certiorari.” That combination suggests that the Court remains open to the value of climate change litigation but is pushing the litigation along a regulatory-focused course.

While this simultaneous preclusion of the common law nuisance pathway and endorsement of administrative challenges reinforces the dominance of regulatory-focused climate change litigation, the opinion also leaves open significant questions that future cases likely will address. First, AEP leaves untouched the large number of cases, generally brought in state courts by individuals and nongovernmental organizations, challenging power plants (especially coal-fired ones) based on their greenhouse gas emissions. Most significantly, the plurality’s affirmation of Massachusetts’s approach to standing, which focuses heavily on the governmental status of some of the petitioners, does not resolve whether it would find standing in a suit with only nongovernmental petitioners. This issue is currently being litigated, and, subsequent to the AEP decision, a federal district court found that a coalition of several citizen environmental groups lacked standing in a challenge to oil and gas leases based on climate change. Second, as discussed in depth in Professor Jim May’s commentary, the Court’s cursory treatment of the political question doctrine provides no guidance regarding whether and when such concerns could arise. The four Justices who found standing held that “no other threshold obstacle bars review,” and the other four Justices did not address additional prudential issues. The divide leaves ambiguity about the Court’s position on the political question doctrine. Third, the opinion explicitly did not reach whether a federal common law nuisance action would be allowed if Congress decided that the EPA could no longer regulate greenhouse gas emissions or whether state law nuisance actions are preempted. The opinion thus limits federal common law as a “parallel track” for challenging the EPA’s regulatory decisions, but maintains future possibilities for courts to be involved in common law nuisance actions. That approach arguably puts pressure on Congress as it considers curtailing the EPA’s ability to regulate greenhouse gases under the Clean Air Act.

Finally, AEP continues an ongoing conversation about the role of federal courts in assessing climate change science. Professor Maxine Burkett and Professor Douglas Kysar have raised concerns about the Court’s increasing skepticism in AEP about the science, especially as compared with Massachusetts. That shift parallels the one in U.S. public opinion over the past several years. However, AEP does not simply focus on the substance of climate science, but also explicitly claims that the EPA is better situated than courts to assess climate change science. The Court explains that “[f]ederal judges lack the scientific, economic, and technological resources an agency can utilize in coping with issues of this order” and then elaborates on specific mechanisms that agencies have and that courts lack. This discussion reinforces both the skepticism that Justice Scalia expressed in the Massachusetts oral argument about his capacity to evaluate climate change science and the Court’s emphasis throughout AEP of the dominance of an agency rulemaking rather than common law approach to this area. In so doing, the Court fails to acknowledge the many contexts in which courts have processed complex science in tort cases, which Professor Wendy Wagner has lauded as “lowering information-related barriers to regulating risky products,” or the individual justice concerns that tort litigation can at times address more effectively than agencies. The Court simply cites Chevron, U.S.A., Inc. v. Natural Resources Defense Council, Inc., a case that, according to Professor Holly Doremus, plays a critical role in judicial deference to agencies’ scientific determinations, without engaging—other than noting in its federal common law analysis that public nuisance law, like the rest of common law, evolves with science—the non-agency-related ways in which courts might appropriately be involved in climate change science.

Overall, the Court’s view of climate change litigation in AEP seems likely to have a mixed impact. On the one hand, the opinion ensures that courts will continue to be an important regulatory battleground in debates over the most appropriate regulatory approach to climate change. The Court not only endorses the appropriateness of suits over the EPA’s approach to regulating greenhouse gases under the Clean Air Act, but also allows this exploding area of litigation to continue—for the most part—along its current trajectory. The increasing investment by law firms, governmental entities, and nongovernmental organizations in climate change litigation practice likely will proceed apace after AEP. In my view, that aspect of the outcome is good news. As displayed in Massachusetts, AEP, and the myriad of cases before lower courts, regulatory litigation provides a means for individuals, nongovernmental organizations, governments, and corporations to address conflicts over the way forward. Numerous cases under the Clean Air Act, Endangered Species Act, Marine Mammal Protection Act, Clean Water Act, Freedom of Information Act, Energy Policy Act, Energy Independence and Security Act, and National Environmental Policy Act have sought to force government action or stop new fossil fuel projects. Some of them have changed governmental behavior. Those cases also put pressure on major carbon emitters to take measures to address their emissions and prepare for a changing regulatory environment.

On the other hand, some of the unanswered questions and closed pathways after AEP raise further questions about the extent to which citizens will be able to use litigation to challenge corporate decisionmaking and to achieve redress for those harmed by climate change. Professor Burkett argues that the Court’s decision to narrow possibilities for federal common law nuisance actions raises serious justice concerns because it eliminates an option for those injured by climate change to obtain corrective justice from major emitters. Although regulatory suits, if they result in greater restrictions on greenhouse gas emissions, help to lessen the impacts of climate change, they provide limited opportunities for victims to obtain redress. Notwithstanding the many procedural and substantive concerns raised by climate change nuisance suits that Professor Michael Gerrard has highlighted (issues that have not yet been addressed for the most part because of the barriers these cases have faced at early stages), these common law actions focus on the victims in a way that regulatory suits generally do not.

Unless the Court’s decision in AEP is accompanied by greater assistance for climate change victims in the regulatory framework, the Court’s emphasis on the agency pathway risks exacerbating the climate justice problem by providing fewer ways for victims to obtain redress. Moreover, addressing climate justice within a federal regulatory framework (even assuming adequate political support for such an approach) raises a host of complex concerns. For example, what should the relationship be between the responsibility of major emitters in mitigation schemes and the efforts to help victims in adaptation ones? How should climate justice fit within nascent federal adaptation efforts, as well as state and local ones? In what way should compensation for harm that goes beyond adaptation assistance (e.g., the inability of the Inuit to use their ancestral lands in line with their traditional practices) be integrated into a regulatory scheme, and how should such compensation be funded? As our three branches of government continue to craft a regulatory framework for climate change following AEP, they need to grapple with those fundamental fairness concerns.

Hari M. Osofsky is an Associate Professor at the University of Minnesota Law School and the Associate Director of Law, Geography, and Environment with the Consortium on Law and Values in Health, Environment, and the Life Sciences. She is also a former Book Reviews Editor for The Yale Law Journal.

Preferred Citation: Hari M. Osofsky, AEP v. Connecticut’s Implications for the Future of Climate Change Litigation, 121 Yale L.J. Online 101 (2011), http://yalelawjournal.org/forum/aep-v-connecticuts-implications-for-the-future-of-climate-change-litigation.