This paper aims to shed light on the potential impact of « facts » on the determination of our moral rights and duties, and more specifically, to identify those empirical circumstances that are likely to short-circuit the application of Right. It will proceed in three steps. First, it will provide a philosophical examination of the apparently contradictory concept of a « right of necessity », as Kant characterises it in his Doctrine of Right. Second, it will investigate to what extent the uncertainty that is peculiar to the Kantian state of nature affects what agents may do or ought to do in this state. Third, it will see how Kant’s understanding of necessity and uncertainty can be related to the legal notions of « state of necessity », “state of emergency”, and “raison d’État”.
