Common law “nuisance” litigation has emerged as the strategy of choice for climate change activists and plaintiffs’ lawyers seeking to limit in a piecemeal fashion U.S. greenhouse gas (“GHG”) emissions. The recent decision by a panel of the United States Court of Appeals for the Fifth Circuit in Comer v. Murphy Oil U.S.A.
, 585 F.3d 855 (5th Cir. 2009), takes this trend to a new level. For the first time, and what some maintain is contrary to established precedent, a United States Court of Appeals has allowed private parties to bring common law nuisance claims in federal court on the theory that particular GHG emissions from defendants’ sources injured plaintiffs and their property by exacerbating specific weather events.