This paper argues that the main conceptualisations of the notion of defeasibility proposed by legal theorists are useful to reconstruct and clarify two different processes. First, legal theorists use the concept of defeasibility to represent a process and the result of a restrictive reinterpretation in which a judge decides that a particular norm is no longer relevant for the regulation of an individual case. Secondly, legal theorists use the concept of defeasibility to describe a process and the result of justifying the non-application of a relevant norm to an individual case.