The Supreme Court today unanimously rejected the effort by some states to sue utilities for greenhouse gas emissions on the basis of the nuisance doctrine, holding that the Clean Air Act pre-empts federal common law.
Although SCOTUS got the right answer in AEP v. Connecticut, it reached it in an unfortunate and ironic manner — i.e., by validating Massachusetts v. EPA, the decision allowing the EPA to regulate greenhouse gases (GHGs). And this validation was done on a unanimous basis (save Sotomayor’s recusal). It should be noted, however, that Justices Alito and Thomas added a concurring opinion that seems to offer only limited support for Massachusetts v. EPA as an expediency in this particular case.
In our favor, SCOTUS did say that the EPA could refuse to regulate GHGs as long as the refusal is not arbitrary and capricious. So skeptics will take today’s win and work toward the next (non-Obama) administration rolling back the endangerment finding.