This Article considers the equal protection “class-of-one” doctrine in light of recent developments, both at the Supreme Court and in the lower courts. After Part I explains the background and current state of the doctrine, Part II considers how that doctrine provides insights into such basic equal protection concepts as discriminatory intent and animus. It also critiques the Court’s analysis of the class-of-one, arguing that the Court has mishandled these concepts and in so doing caused doctrinal anomalies and lower court confusion. Part II offers an alternative approach to the class-of-one that corrects those problems while still addressing the concerns that may have influenced the Court to embrace its mistaken analysis.

Part III considers how the Supreme Court’s mishandling of the class-of-one risks infecting other areas of equal protection law and American constitutionalism more generally. It explains how the Court’s approach threatens the core constitutional commitment that government action must seek to promote a public purpose. It also discusses a subsequent Court decision that cites its most recent classof- one case in a way that aggravates that threat. The Article concludes by calling on the Court to reconsider both its aggressive reading of its class-of-one jurisprudence and the direction of that jurisprudence itself, in order to reverse the doctrinal and conceptual damage it has caused. The Article thus demonstrates that the classof- one provides insight into larger equal protection issues. At the same time, it risks infecting those larger issues with the mistakes flowing from the Court’s mishandling of this under-studied and poorly understood doctrine.