The Supreme Court of the United States has granted certiorari in the Second Circuit's Connecticut v. American Electric Power decision, which allowed federal common law nuisance claims to proceed against several utilities because of their greenhouse gas emissions. Among the issues raised are whether federal environmental programs now preempt the field and whether the case should be dismissed under the political question doctrine or on standing grounds.

In Spring 2011 the Supreme Court of the United States will hear an appeal of State of Connecticut v. American Electric Power Co., 582 F.3d 309 (2d Cir. 2009), which determined that eight states, as well as New York City and three environmental land trusts, could bring federal common law nuisance claims against six electric power corporations. The claims were intended to cap and then reduce carbon dioxide emissions from what were alleged to be the five largest emitters of carbon dioxide in the United States, with fossil fuel-fired power plants in 20 states. The Second Circuit reversed a lower court decision dismissing the lawsuit under the political question doctrine, i.e., that claims which present non-justiciable political questions cannot be decided by the judiciary.