The U.S. Supreme Court said it would hear a challenge to a court of appeals decision allowing several states to maintain a public nuisance lawsuit against American Electric Power Co. and other utilities for their greenhouse gas (GHG) emissions.

The Second Circuit decision allowed Connecticut, seven other states, New York City and three environmental groups to proceed with lawsuits against AEP, the Tennessee Valley Authority, Duke Energy, Southern Co. and Xcel Energy. The lawsuit alleged the power companies’ carbon dioxide emissions constituted a nuisance under federal common law. The companies, except for the TVA, asked the Supreme Court in August to reverse the lower court’s decision arguing the plaintiffs lacked standing because they cannot trace their injuries directly to the utilities’ activities. They also argued that federal common law has been “displaced” with respect to greenhouse gas-related lawsuits by regulation under the Clean Air Act.

If the lawsuit by the states and environmental groups were to go forward, it could signal that the court is allowing challenges to a company’s GHG emissions under nuisance law, which would provide environmental advocates with another tool to try to curb emissions. If the Second Circuit decision were upheld, it would allow parties to go directly to court to seek a remedy, rather than rely on regulatory agencies alone.

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