Definition
Leges non scripte (Latin: "unwritten laws") is a term from English legal tradition referring to laws that derive their authority not from formal legislative enactment or written text, but from long-standing custom, usage, and practice. The category encompasses the common law as developed through judicial decision and customary observance, as well as certain ancient acts of Parliament so old that no written record of their original enactment survives — statutes whose authority rested, practically speaking, on immemorial usage rather than recoverable text.
The term stands in contrast to leges scripte, the written or statute law: those rules enacted by a sovereign legislative body and recorded in a definitive written form. Together, the two categories formed the classical English division of the whole body of law.
Why It Matters in Research
Researchers working in early English legal sources will encounter leges non scripte as a structural organizing concept, not merely a descriptive label. Blackstone and Hale both relied on this division to explain the dual foundations of English law, and understanding it is essential for reading their frameworks correctly.
The most important practical trap: the category is broader than "common law" alone. It also absorbed ancient parliamentary enactments that had lost their written records — a wrinkle that complicates clean distinctions between "statute" and "common law" in early modern English sources. A researcher who assumes leges non scripte means only judge-made law will misread Hale's treatment in the History of the Common Law.
The term also surfaces in discussions of customary law at the local level — borough customs, manorial practices, trade usages — all of which could qualify as leges non scripte in the right analytical context. When tracing the authority of a local custom in historical sources, encountering this term signals that the author is placing that custom within the recognized, legitimate category of unwritten law, not dismissing it as mere informal practice.
Modern researchers should note that the leges scripte / leges non scripte division largely dropped out of American legal discourse, where the common law was received as a body of law but the philosophical scaffolding of the English dual-source framework was rarely reproduced. Sources written after the early nineteenth century, particularly American sources, seldom use the term at all. Its appearance in a document is itself a dating and provenance signal.
Historical Dictionary Support
Burrill's Law Dictionary follows the standard formulation traceable directly to Hale and Blackstone: leges non scripte are unwritten or customary laws, including those ancient acts of parliament antedating time of memory. The entry is concise and points researchers directly to Hale's History of the Common Law and Blackstone's Commentaries (1 Bl. Com. 63–64) — the two foundational loci for this concept.
Blackstone's treatment is the more expansive of the two. He describes leges non scripte as receiving their binding force not from any formal promulgation but from long and immemorial usage, the consent of the governed expressed through time rather than through legislative act. Hale's framing is similar but emphasizes the practical consequence: ancient statutes whose original enactment is unrecoverable are functionally indistinguishable from customary law and are therefore absorbed into the same category.
What historical dictionary sources largely omit is any sustained treatment of the tensions within the category — the difficulty of distinguishing ancient custom from ancient statute, or of establishing the "time of memory" threshold in practice. These were live problems in early modern English courts but tend to be flattened in the dictionary treatment, which presents the category as tidier than it was in application.
Jurisdictional Note
The term is specific to English legal tradition and appears almost exclusively in English and British sources or in works directly derived from them. American jurisdictions received the common law but did not carry forward this Latin taxonomic framework in any systematic way. Researchers working in American legal history should treat the term as a marker of English or Anglo-colonial sources.