Definition
De escambio monetae (Latin: "of the exchange of money") is an ancient English common law writ authorizing a merchant to draw a bill of exchange — that is, to create a written instrument directing a third party to pay a specified sum of money to the bearer or a named payee. The writ functioned as a formal royal or judicial sanction for the mercantile practice of currency exchange by written instrument, reflecting the period when such commercial instruments required affirmative legal authorization before they could be lawfully issued or enforced.
Why It Matters in Research
This term appears almost exclusively in pre-modern English legal sources and registers of writs. Researchers encountering it will most likely do so in historical documents concerning the early law merchant, medieval commercial practice, or the procedural forms catalogued in the Registrum Brevium (Reg. Orig.). It has no practical application in modern legal research but serves as a marker for understanding how bills of exchange — instruments that became the foundation of modern commercial paper and negotiable instruments law — entered English law not as organic mercantile custom freely exercised, but as a licensed or writ-sanctioned practice.
The key research connection is the transition: the necessity for a writ like de escambio monetae was eventually superseded as the law merchant became absorbed into the common law and bills of exchange became freely negotiable instruments without need of prior royal authorization. Researchers tracing the development of negotiable instruments law should treat references to this writ as evidence of the earlier, more restrictive regulatory posture toward commercial paper. A researcher who encounters this term in a primary source and mistakes it for a straightforward writ of debt or a general money judgment writ will misread the document's commercial context entirely.
Because the term appears in the supplemental material to Black's 2nd edition rather than the main body, it likely migrated from specialized registers of writs and older English treatises. Law Mind corpus researchers should not expect to find it in American legal materials; its natural habitat is English ecclesiastical and mercantile court records, Year Books, and early Chancery practice.
Historical Dictionary Support
Black's Law Dictionary (2nd Ed., Supplemental) defines de escambio monetae as "a writ of exchange of money" and describes it as an "ancient writ to authorize a merchant to make a bill of exchange (literas cambitorias facere)," citing Reg. Orig. 194 — a reference to the Registrum Brevium Originalia, the standard medieval English register of original writs. This is the sole entry among the Law Mind historical dictionary sources, and it is characteristically spare: Black's provides the translation and functional description but offers no procedural detail, no account of how the writ was obtained, and no explanation of what remedies or consequences flowed from acting without it.
What the historical sources do not address is the broader legal architecture this writ inhabited. Bills of exchange, as instruments of the international law merchant, existed in tension with the jurisdictional ambitions of English common law courts throughout the medieval and early modern periods. The writ of de escambio monetae reflects one mechanism by which the common law attempted to assert some supervisory role over merchant practice — a role that common law courts ultimately consolidated not through writs of this kind but through the eventual incorporation of law merchant principles into common law doctrine, a process largely complete by the eighteenth century.
Researchers should note that the Latin phrase in Black's entry appears with a minor transcription variant — "Jacere" in the printed text is an artifact of early typesetting conventions in which the long "s" (ſ) or certain italic letterforms were rendered as "J"; the correct Latin infinitive is facere, meaning "to make" or "to draw."
Jurisdictional Note
This writ is a creature of English law with no American jurisdictional counterpart. It predates the American legal system entirely. Any appearance of this term in American legal materials would be as a historical reference or as part of a scholarly treatment of the origins of negotiable instruments law.