Abstract
In his influential work, The Concept of Law, H. L. A. Hart levels several criticisms at the traditional natural law principle: lex iniusta non est lex. Although some of his criticisms have received a great deal of careful evaluation, others have not. In this paper I will focus on several ways in which Hart attempts to undermine the value of this principle. I will pay particularly close attention to his claims concerning the unfortunate effects that follow from either scholars’ or ordinary citizens’ acceptance of this principle. It is my aim to show that his criticisms of this principle fail. It must be noted that my end is a modest one. I do not attempt to clear all possible objections to this principle, nor conclusively prove its value, but merely show that one set of arguments against it fails. Although this aim is surely modest, it is, I contend, nonetheless important. Investigating the relationship between morality and legality is undoubtedly one of the central tasks of legal philosophy. Since the time of Plato, natural law theories, although differing on various particulars, have proposed a powerful answer concerning this relationship. It is clear that these theories no longer receive the attention they once did, at least in part because of Hart’s objections. I intend to show that these objections fail to show the inadequacy of the lex iniusta principle.