[T]he Supreme Court has held that federal common law addressing domestic greenhouse gas emissions has been displaced by Congressional action. That determination displaces federal common law public nuisance actions seeking damages, as well as those actions seeking injunctive relief. The civil conspiracy claim falls with the substantive claim. Therefore, we affirm the judgment of the district court. ... [T]he solution to Kivalina's dire circumstance must rest in the hands of the legislative and executive branches of our government, not the federal common law.

In Massachusetts v. EPA [Duke Law case backgrounder] the court found that the Environmental Protection Agency (EPA) [official website] had the authority to regulate greenhouse gas emissions under the Clean Air Act and its failure to set applicable standards without reason was no in accordance with law. Yet the EPA has experienced few victories recently. Last month, the US Court of Appeals for the District of Columbia Circuit [official website] ruled [JURIST report] that the EPA overstepped its authority under the Clean Air Act (CAA) [text, PDF] when it issued a regulation limiting power plants' emissions that cross state lines. A DC Circuit decision upholding the EPA's plan to add more ethanol to gasoline [JURIST report] marked a rare victory for the EPA. The US Court of Appeals for the Fifth Circuit [official website] ruled [JURIST report] that the EPA also overstepped its bounds when it rejected a Texas plan to issue air permits. In early August, the US District Court for the District of Columbia [official website] ruled [JURIST report] that the EPA violated several environmental statutes when it issued regulations on coal mining in the Appalachia region.