There are two distinct types of legal wrongdoing: civil and criminal. This article demonstrates in three ways that Immanuel Kant’s Universal Principle of Right, properly interpreted, offers a plausible and resilient account of this important distinction. First, Kant’s principle correctly identifies attempted crimes as crimes themselves even when they do not violate the rights of any individual. Second, it justifies our treatment of reckless endangerment as a crime by distinguishing it from ordinary negligence, which traditionally is only civilly wrong. Third, it justifies differences between the way in which we determine criminal punishments and the way in which we measure civil remedies. Moreover, the Universal Principle of Right yields a ...