Definition
A writ of prohibition directed to justices, commanding them not to proceed with an assize in a particular case. The writ operated as a check on the assize courts, halting proceedings when a superior authority determined that a matter should not be heard by that tribunal. It belonged to the broader family of writs of prohibition — royal instruments used to restrain inferior courts or officers from exercising jurisdiction improperly or beyond their competence.
Why It Matters in Research
This term is almost exclusively a historical artifact. Researchers will encounter it in medieval and early modern English legal records, treatises on the register of writs, and scholarship on the development of the English writ system. It does not appear in modern procedural practice and has no living statutory or common law counterpart in any contemporary jurisdiction.
The key research context is the assize system itself. Assizes were commissions of royal justices sent into the counties to hear particular classes of action — principally real property disputes — and their jurisdiction was defined and limited by the specific writs that called them into being. A writ de non procedendo ad assisam was the mechanism by which that jurisdiction could be suspended or negated in a given case. Understanding why such a writ might issue requires knowledge of the competing jurisdictional claims between royal courts, ecclesiastical courts, and other tribunals in medieval England.
Researchers working in the Registrum Omnium Brevium (Register of Writs) — the source cited in Black's — will find this writ catalogued alongside other prerogative and prohibitory writs. The Register is a formulary: it records the approved forms of writs rather than the substantive law behind them. Black's citation to "Reg. orig. 221" points to the Registrum Originale, one version of the Register, and researchers should be aware that different manuscript and printed editions of the Register exist, with varying pagination and organization.
The term also signals a research path into Fitzherbert's Natura Brevium and similar treatises on the writ system, where the practical circumstances under which prohibitory writs issued are discussed in greater detail than the Register itself provides.
Historical Dictionary Support
Black's Law Dictionary (2nd Ed., Supplemental) provides the only available dictionary definition in the Law Mind corpus: "A writ forbidding the justices from holding an assise in a particular case," with the sole authority given as Reg. orig. 221. The entry is characteristic of Black's treatment of obsolete Latin writs — a compressed functional description with a register citation and nothing further.
The historical dictionary record for this term is thin, reflecting how rarely it was the subject of doctrinal analysis. It was a procedural instrument, catalogued in formularies and occasionally referenced in treatises on writs, but it generated little commentary of its own. Researchers should not expect to find extended treatment in early modern legal dictionaries or abridgements. The deeper analysis, such as it exists, is embedded in historical scholarship on the assize system and the register of writs rather than in the dictionary tradition.
Jurisdictional Note
This writ is exclusively English in origin and application. It has no counterpart in American, Scottish, or other common law jurisdictions. Researchers in non-English legal history will not encounter it outside of comparative or historical discussions of the English writ system.