Public Nuisance under Federal Common Law - Huh?

This site contains information about the interplay between public nuisance theories and climate change litigation. (See, Global Warming and Public Nuisance Part I and Part II).  A new development in that area is the Second Circuit's 139-page opinion in State of Connecticut v. American Electric Power Co. Inc., 05-5104-cv (2d Cir., Sept. 21, 2009). In that case, the Federal Court of Appeals held state governments (in this case, Connecticut, California, Iowa, New Jersey, Rhode Island, Vermont, Wisconsin, and New York) can sue utilities under federal common law theories of public nuisance for contributing to global warming. This ruling reversed the district court's decision that such claims would interfere with the responsibilities of the political branches.

An interesting part of the opinion, tossed up at the second-to-last page at the end of a very long read, is the court's observation that the plaintiffs had alleged, as an alternative to their federal claims, that defendants were liable under the statutory and/or common law of public nuisance of each state where fossil-fueled fired electric generating facilities are, at a minimum, located. Addressing these claims, the court says: "In Milwaukee II, the Supreme Court observed that federal and state nuisance law could not both apply to the case. 'If state law can be applied, there is no need for federal common law; if federal common law exists, it is because state law can not be used.'" (Connecticut Opinion, p. 138, emphasis added.) And that is, indeed, precisely what the Supreme Court said in City of Milwaukee v. Illinois, 451 U.S. 304, 312-14, 101 S.Ct. 1784, 1790-91, 68 L.Ed.2d 114 (1981)."In this regard, we note the inconsistency in Illinois' argument and the decision of the District Court that both federal and state nuisance law apply to this case. If state law can be applied, there is no need for federal common law; if federal common law exists, it is because state law cannot be used." 

In the very next sentence of its own opinion, however, the Second Circuit adds, "Accordingly, since we hold that the federal common law of nuisance applies in this case, we do not address the States' and Trusts' alternative claims based on state public nuisance law." (Connecticut Opinion, p. 138, emphasis added.) Now, based on the quoted language from City of Milwaukee, isn't this putting the cart before the horse? Wasn't the court supposed to address those alternative claims based on state public nuisance law before deciding if federal common law was needed to fill the gap?

These aren't idle questions. As we've noted in previous blog posts, state law public nuisance claims are increasingly being prosecuted by state governments, and this new Second Circuit decision makes one wonder whether the government plaintiffs will now try to tack on federal common law claims as well. See Tafflin v. Levitt, 493 U.S. 455, 458 (1990) ("[W]e have consistently held that state courts have inherent authority, and are thus presumptively competent, to adjudicate claims arising under the laws of the United States.").