The Causation Canon

It is rare to witness the birth of a canon of statutory interpretation. In the past decade, the Supreme Court created a new canon-the causation canon. When a statute uses any causal language, the Court will assume that Congress meant to require the plaintiff to establish "but-for" cause. This Article is the first to name, recognize and discuss this new canon. The Article traces the birth of the canon, showing that the canon did not exist until 2013 and was not certain until 202o. Demonstrating how the Court constructed this new canon yields several new insights about statutory interpretation. The Supreme Court claimed the new causation canon represents "ancient" and "long-held " principles of common law. The Supreme Court's claims about the causation canon are easily disprovable with only a cursory review of Supreme Court cases from the past forty years. This is not a case of a contested or difficult historic record. In creating the causation canon, the Court did not simply apply the common law to statutes. Instead, it constructed its own new federal causation standard that is not consistent with any state's common law or even the Restatement of Torts. The Court significantly changed the common law and then magnified the significance of the change by imposing it as a default statutory interpretation canon that will apply across both civil and criminal federal statutes. This new canon represents a significant change in the way the Supreme Court has used the common law, and it does not fit comfortably within claims made about textualism generally or substantive canons specifically. Creating a new federal common law offactual cause and imposing that newly created law as a default standard significantly raises the profile of this area of statutory interpretation and demands greater scholarly inquiry. Elwood L. Thomas Missouri Endowed Professor of Law, University of Missouri School of Law. I would like to thank Lou Bilionis,Jessica Clarke, Katie Eyer, Emily Houh, Kristin Kalsem, Anita Krishnakumar, Brad Mank, Janet Moore, Meghan Morris, Michael Solimine, Joe Tomain, and Deborah Widiss for helpful comments on earlier drafts of this Article and the University of Cincinnati College of Law Summer Workshop Series, which provided an important opportunity to talk through early ideas. I also deeply appreciate the work of my research assistants Brandon Breyer and Mallory Perazzo.