Definition
Collaterales et socii is a Latin phrase meaning, literally, "lateral companions and associates." In English legal history, it denotes the former title of the officers who assisted the Lord Chancellor in the exercise of his judicial and administrative functions — the officials later known as masters in chancery. The term reflects the physical and institutional arrangement by which these officers sat alongside the Chancellor at a designated table in Westminster Hall and in other venues where chancery business was conducted.
Why It Matters in Research
This term functions almost exclusively as a historical label. Researchers encountering it in early common law sources, particularly in Latin chancery records and older treatises on equity procedure, should understand that it is a predecessor designation for the masters in chancery — an office with a long, evolving history in English equity practice. The term does not appear in modern legal usage, and no contemporary institutional counterpart carries this name.
The chief research risk is failing to connect this archaic title to the mature office of master in chancery when tracing the development of equity jurisdiction. Sources from different periods use different nomenclature for what is essentially the same or a functionally related office. A researcher working in medieval chancery records may encounter collaterales et socii and not immediately recognize these figures as the ancestors of the masters in chancery who appear so prominently in later equity treatises and in the procedural reforms of the nineteenth century.
The term also carries spatial and ceremonial significance that is substantively informative: the phrase encodes the institutional relationship of these officers to the Chancellor. Their seating arrangement — beside rather than subordinate in the clerical sense, yet clearly assistants — illuminates the collegial, quasi-conciliar character of early chancery practice before it hardened into a formal court with defined procedural roles. This context matters when interpreting the scope of authority these officers exercised in early records.
Researchers working with Reeves' History of English Law or with Fleta, the two sources cited in Burrill, should treat those as primary navigational anchors. Reeves situates the office historically; Fleta (a late thirteenth-century treatise) provides near-contemporary institutional description. The Treatise of the Maisters of the Chauncerie, also noted by Burrill, is a more directly focused source on the office itself and its transition toward the later designation.
Historical Dictionary Support
Bouvier offers only the bare identification: collaterales et socii were the former title of masters in chancery. Burrill supplies the substantive content. He glosses the phrase as "assessors; assistants and associates [of the chancellor]" and explains the etymological logic: these officers sat by the Chancellor's side (collaterales, lateral or side-by-side) at a particular table in Westminster Hall and elsewhere. Burrill cites Reeves' History of English Law (vol. 2, p. 251), Fleta (book 2, chapter 13, section 12), and the Treatise of the Maisters of the Chauncerie in support.
Neither dictionary ventures beyond identifying the term as a historical predecessor title. Neither discusses the transition from this designation to the fully developed office of master in chancery, nor the procedural history of what these officers actually did. Researchers should treat both entries as pointers to primary sources rather than as substantive accounts of the office's functions or jurisdictional scope.
Encyclopedia Cross-Reference
See: Masters in Chancery; History of the Court of Chancery