Definition
A Latin term of medieval English legal practice referring to a person who appears and answers in court on behalf of another party, at an assigned day, for the purpose of winning or losing the action. The phrase translates literally as "one who responds to gain or to lose" — that is, a representative who stands in for an absent principal to bear the outcome of the proceeding. The role was functionally equivalent to that of a proctor, attorney, or deputy in early English court procedure.
The term captures a specific procedural reality of medieval litigation: parties were often unable or not required to appear personally at every stage of a suit, and a designated representative would attend court at the appointed day, ready to advance or defend the claim as if standing in the principal's shoes entirely.
Common Confusion
This term is sometimes loosely equated with "attorney" in its modern sense, but the resemblance is superficial. The responsalis was not primarily a legal adviser or advocate in the contemporary sense — the role was essentially one of procedural attendance and formal representation at a fixed court date. The emphasis was on physical presence and authorized response at a designated day, not on ongoing counsel or strategic management of a case. Conflating this figure with the modern attorney obscures the highly formalized, appearance-centered nature of early English court procedure.
Why It Matters in Research
This term appears almost exclusively in sources dealing with early and medieval English law. Researchers encountering it in historical legal records, Year Books, or treatises on early English procedure should understand it as a term of art tied to the day-certain system of medieval court scheduling, where failure to appear at the assigned day could result in default or loss of the action. The responsalis existed precisely to prevent that outcome for an absent party.
The term has no modern operational equivalent in Anglo-American practice under that name, and it does not appear in standard modern legal dictionaries. Researchers working with early plea rolls, ecclesiastical court records, or treatises such as Reeve's History of English Law will encounter this term as part of a broader vocabulary of medieval procedural representation that includes procurators, attorneys-in-fact, and essoiners. Understanding the distinction among these roles is important for correctly interpreting what a historical record is actually describing when a party is represented at court.
One research trap: do not read the phrase "ad lucrandum vel petendum" in isolation and assume it describes only plaintiffs seeking gain. The formula covers both sides — the representative could appear to defend against a claim just as much as to press one. The phrase signals full authorization to bear whatever outcome the day's proceedings produce.
Connections to the broader Law Mind corpus include entries on early forms of legal representation, the essoin system, proctors in ecclesiastical courts, and the historical development of the attorney's role in English common law.
Historical Dictionary Support
Black's Law Dictionary (2nd Ed., Supplemental) provides the sole dictionary source for this entry, defining the responsalis ad lucrandum vel petendum as "he who appears and answers for another in court at a day assigned; a proctor, attorney, or deputy," and citing Reeve's History of English Law. The entry is brief and unremarked, offered without elaboration on procedural context or historical development.
No other major historical legal dictionaries in the Law Mind corpus — including Bouvier, Burrill, or Jacob — carry a dedicated entry for this precise phrase, which itself signals how narrow and specialized the term is. Reeve remains the primary substantive source for understanding the role in practice. Researchers requiring depth beyond Black's brief treatment should consult Reeve directly, along with Pollock and Maitland's History of English Law, which addresses the general system of representation in early English courts without always using this specific Latin formula.
Jurisdictional Note
This term belongs entirely to historical English law. It has no recognized modern application in any common law jurisdiction and does not appear in current procedural codes or rules of court. Its relevance is confined to research in legal history, medieval procedure, and the history of legal representation in England.