Legal Sources, the Rule of Recognition, and Customary Law

Abstract

A perennial puzzle about source-based law such as precedent is what makes sources legally binding. One of the most influential answers to this puzzle is provided by Hart’s rule of recognition. According to Hart, the sources of law are accepted as binding by the officials of a legal system, and this collective social practice of officials provides the foundations for a legal system. According to Hart, the rule of recognition differs fundamentally from other legal rules in three ways: (1) the grounds on which it is accepted; (2) the basis for its system-membership; and (3) its mode of existence. This paper argues that (1) should be rejected, and that (2) and (3) do not in fact make the rule of recognition fundamentally different to other legal rules in the way that Hart supposed. Instead, the rule of recognition is a form of customary law in foro whose existence is practice-dependent, but which is nonetheless just as much a law of the system as other laws are. The rule of recognition provides a foundation for source-based law, but on that is internal to the system.