Legal Positivism: Austin, Hart, and the Separation Thesis

Legal positivism denies that law's validity depends on its moral merit: what the law is and what the law ought to be are, on this view, conceptually distinct questions, a claim usually called the separation thesis. Its modern origin is often traced to Jeremy Bentham (1748–1832) and, more systematically, to John Austin (1790–1859), whose lectures published as The Province of Jurisprudence Determined (1832) propose the "command theory of law": law is the command of a sovereign — a person or determinate body habitually obeyed by the bulk of a political society and itself habitually obeying no one else — backed by the threat of a sanction for noncompliance. Austin's sovereign-command model gave positivism its first rigorous, systematic form, deliberately excising natural law's moral criteria of validity, but it struggled to explain several familiar features of real legal systems, including laws that confer powers rather than impose duties (such as the rules for making a valid will or contract), the continuity of legal authority across a change of sovereign, and the fact that a modern sovereign, such as a legislature, is itself typically bound by legal rules (a constitution) rather than standing wholly above the law as Austin's model requires.