State and Federal Models of the Interaction between Statutes and Unwritten Law
This Article argues that modern courts read individual federal statutes to encompass more issues than identically worded state statutes would be understood to cover. There are many questions that regularly arise in the implementation of statutes but that the typical statute does not say anything about. When a state statute is silent on such questions, state courts often conclude that the questions lie beyond the statute’s domain and that the answers therefore come from the state’s version of the common law. But when a federal statute is silent on the same sorts of questions, courts often act as if answers should be imputed to the statute itself.
As an illustration of this difference, the Article studies how courts decide whether forum law governs cross-border events. When state courts need to determine whether one of their own state’s statutes supplies rules of decision for a case involving cross-border events, they commonly apply an overarching set of choice-oflaw doctrines that they think of as operating outside the statute. By contrast, when a federal statute does not specifically address its applicability to cross-border events, courts use a canon of construction—the presumption against extraterritoriality—to import the necessary distinctions into the statute.
Similar examples abound. In a range of different contexts, general legal questions that would be thought to fall outside the domain of the typical state statute (and that courts might therefore handle as a matter of unwritten law) are presumed to lie inside the domain of the typical federal statute (with the result that courts handle them under the rubric of statutory interpretation). To explain this pattern, the Article points to practical concerns that came into focus after Erie Railroad Co v Tompkins: under modern doctrine, one way for federal judges to avoid having to accept whatever state courts say about questions that arise in connection with the implementation of a federal statute is to read the statute itself to encompass those questions.
The consequences of shoehorning general legal questions into the domains of individual federal statutes depend on the interpretive techniques that courts use. To the extent that the rubric of statutory interpretation leads courts to give statutespecific answers to such questions, the federal model can produce dramatically different results than the state model would. Those differences will be muted if courts instead read each individual federal statute as implicitly incorporating generic principles of unwritten law. Even then, though, the mechanism through which those principles operate can have subtle effects.