Is "customary law" a redundancy? Jeremy Bentham and John Austin both came close to believing that the very idea of customary law was essentially a contradiction in terms,' but few these days take such a dim view of the legal status of custom.2 Yet although such extreme skepticism about the legality of custom might now be a bit passé, custom's role in a legal system still remains somewhat of a puzzle. Initially, for example, we might wonder about just how the customs, habits, or practices of ordinary people can become law. If law is prototypically created by legislatures and other bodies clothed with formal governmental authority, as classical positivists such as Bentham and Austin believed, then how is it that law can emerge from the practices of ordinary people? This question forms the beginning of the puzzle, because when we answer this question (and especially if we answer it by referring to the way in which such practices might be adopted, internalized, and applied by courts), we then become hard-pressed to distinguish the way in which custom acquires the status of law from the way in which we understand positive law generally, at least in a post-Hartian world.' And when we see the legality of custom in terms of the internalization of norms by judges rather than exclusively as the issuance of orders by the sovereign, we must then confront further questions relating to how customary law differs, if at all, simply from law. These, in a nutshell, are the questions I propose to address here.
The argument I advance in this Article commences with the widely accepted notion that the custom that does or can have the status of law must be a normative custom and not merely a description of a non-normative empirical regularity.4 That is, a custom, to be available as a genuine source of law under the traditional common law view, must be understood to exist as of right. To qualify as enforceable law, the custom must, even prior to its formal recognition by the courts, have created in some people an obligation to conform,5 and consequently have created a claim of right (even if not a formal legal one) on the part of those aggrieved by the nonconformance of others. This principle is standard common law fare, but it generates a puzzle. At least since H.L.A. Hart,fi and perhaps earlier,7 most legal theorists, or at least most legal theorists in the positivist tradition, have accepted that the internalization of a rule of recognition, or, more precisely, the official internalization of the ultimate or master rule of recognition, is both a necessary and sufficient condition for the existence of law." But, the internalization of a rule of recognition as a criterion for law then begins to resemble the criteria for recognition of custom as a valid source of law. To the extent that this is so, there emerges the possibility that internalized normative custom simply is law, and in large part law simply is internalized custom. Insofar as these claims are true, then the legality of custom is not the puzzle that many legal theorists in the positivist tradition, including Hart himself, have sought to solve. Instead, it may be that the internalization of a rule of recognition is best explained in ways that make custom not merely a puzzling, if minor, appendage to the larger positivist picture of law, but instead an important component of the foundations of all of law. Or so I will argue here.
I. Bentham, Austin, and the Skeptical Tradition
Modern jurisprudence, especially in the legal positivist tradition, begins with Jeremy Bentham.'' His principal work of legal theory-now published as Of the Limits of the Penal Branch of Jurisprudence(TM)-remained largely undiscovered and thus unknown until the 1930s." By that time, John Austin's exposition and development of themes that had actually originated with Bentham had long emerged as the canonical positivist text.12 Bentham's thoughts about the nature of law, and about the role of custom within it, have consequently come to us primarily through Austin, although it is certainly likely that Austin's presentation owes much to Austin's own ideas as well. …