Definition
A historical writ directing a sheriff to impanel (empanel) a jury for an assize or real action. The writ was a procedural instrument of medieval English common law, commanding the sheriff of a county to select and summon the jurors necessary to constitute an assize — a form of jury-based proceeding used primarily to resolve disputes over land and related property rights. The writ belongs to the broader family of writs that administered the machinery of the early common law courts, ensuring that the jurors required to hear a matter were properly assembled before the tribunal.
Common Confusion
The term should not be confused with the assizes themselves. The assize was the proceeding or tribunal; ponendis in assisis was the ancillary writ that set that proceeding in motion by compelling the sheriff to furnish a jury. Researchers encountering references to assizes in historical records should distinguish between the substantive proceeding (the assize) and the administrative writs — including this one — that supported it.
Why It Matters in Research
This term is essentially a fossil of medieval English procedural law and will appear only in historical sources. Researchers are unlikely to encounter it in any living legal context. Its research relevance is therefore narrow but specific:
First, the writ surfaces in treatises and formularies on the old common law forms of action, particularly those addressing real actions and the assizes of novel disseisin, mort d'ancestor, and darrein presentment. A researcher working through historical pleading manuals or Year Book materials may encounter the writ as part of a broader procedural sequence.
Second, the Latin phrasing matters for search purposes. Historical legal records — plea rolls, assize rolls, and chancery records — may use the Latin form without gloss. Researchers working in primary sources from medieval English courts should recognize the phrase as a jury-empanelment writ rather than a substantive writ going to the merits of a claim.
Third, this writ illustrates an important structural feature of the old common law system: the separation of the writ commanding an action from the writ administering the jury machinery. Modern procedure collapses these steps; historical procedure did not. Understanding this distinction helps researchers read historical pleading records accurately and avoid misattributing procedural significance to what is, in substance, a housekeeping command to the sheriff.
No meaningful jurisdictional variation exists for research purposes — the writ is exclusively an English common law artifact and was not carried forward in any adapted form into American practice.
Historical Dictionary Support
The three source dictionaries — Black's (both editions) and Bouvier's — are in complete agreement, offering nearly identical one-sentence definitions. None of the sources elaborates beyond the bare description of the writ's function, reflecting that by the time these dictionaries were compiled, the writ had long since passed out of practical use. Bouvier's cites Mozley & Whiteley's Law Dictionary and Wharton's Law Lexicon as supporting references, both of which treat the term in similarly compressed fashion.
The historical dictionaries do not address the procedural context in which the writ operated — the assize system, the forms of real action, or the sheriff's role in jury selection — leaving researchers who need more than a bare identification of the term to look beyond these sources to treatises on the old forms of action, such as Blackstone's Commentaries, Fitzherbert's Natura Brevium, or Staunford's Les Plees del Coron for comparative procedural context.