American Electric Power Co., Inc. v. Connecticut

In American Electric Power Co., Inc. v. Connecticut, 131 S. Ct. 2527 , 2535 (2011) (AEP), eight states, the city of New York, and three private land trusts brought a public nuisance action against the five largest emitters of carbon dioxide in the United States. Id. at 2533-34. The AEP plaintiffs alleged that defendants carbon-dioxide emissions created a substantial and unreasonable interference with public rights, in violation of the federal common law of interstate nuisance, and sought injunctive relief through a court-ordered imposition of emissions caps. Id. at 2534. Concluding that the Clean Air Act already provides a means to seek limits on emissions of carbon dioxide from domestic power plants, the Supreme Court in AEP held that the Clean Air Act and the EPA actions it authorizes displace any federal common law right to seek abatement of such emissions. Id. at 2537-38. In AEP, several States, a city, and three private land trusts brought fed- eral common law nuisance abatement claims against four pri- vate power companies and the federal Tennessee Valley Authority. 131 S. Ct. at 2532. The AEP plaintiffs sought injunctive relief in the form of emissions caps on the five defendants, whom the complaints identified as the five largest carbon dioxide emitters in the United States. Id. at 2534. The Supreme Court held that the CAA and the EPA actions it authorizes displace any federal common law right to seek abatement of carbon-dioxide emissions from fossil-fuel fired power plants. Id. at 2537. The Supreme Court noted that greenhouse gases were air pollutants subject to EPA regula- tion after Massachusetts, and the CAA speaks directly to carbon dioxide emissions from stationary sources such as the AEP defendants plants. Id.