Definition
Senatus decreta (Latin: "decisions of the senate") refers, in Roman and civil law, to the private acts or decrees of the Roman Senate that concerned particular persons or individual matters, as distinguished from general legislation applicable to all. These were essentially ad hoc resolutions — pronouncements of the senate directed at specific individuals, disputes, or circumstances rather than at the broader public order. They did not carry the force of general law in the way that senatus consulta did, but operated instead as binding determinations within their narrow factual context.
Common Confusion
Researchers frequently conflate senatus decreta with senatus consulta. The distinction is fundamental: a senatus consultum was a general enactment or advisory opinion of the Roman Senate carrying broad legislative or quasi-legislative force, often cited as a source of Roman law applicable universally. A senatus decretum, by contrast, was particular and personal in its reach — closer to a private ruling or order than to public legislation. In civil law sources, a reference to the senate's legislative authority almost always signals senatus consulta; references to senatus decreta signal individualized determinations that cannot be generalized into rules of wider application.
Why It Matters in Research
The primary research significance of senatus decreta lies in how they are categorized within civil law taxonomy. A researcher working through Roman law sources, canon law commentaries, or early civil law treatises must be alert to whether a given senatorial act is characterized as a decretum (particular, personal) or a consultum (general, quasi-legislative). Misreading a decretum as a source of general legal principle will distort analysis of the underlying rule, because decreta were not intended to bind beyond their immediate subject.
In the Law Mind corpus, the term appears most naturally in foundational civil law texts and in the historical background sections of works treating Roman law sources. It is rarely the operative term in common law materials, but it surfaces in annotations and comparative notes within treatises that trace the genealogy of legal concepts — particularly those dealing with the authority of deliberative bodies, private bills, and acts of attainder or relief. The analogy to private or special legislation in common law systems (acts directed at named individuals rather than the public) is instructive and occasionally made explicit in secondary sources.
Researchers should also note the sequencing: in Roman legal theory, the hierarchy of sources placed senatus consulta above decreta in terms of generative legal force. A decretum settling a matter between named parties did not establish precedent in the Roman sense; it resolved a case. This distinction anticipates, in rough form, the common law distinction between legislation and adjudication — and some civil law scholars draw that line explicitly when discussing Roman sources.
Historical Dictionary Support
The four source dictionaries are in close agreement, which itself is informative: the definition of senatus decreta is settled and uncontested in the historical record. Black's (both editions), Rapalje & Lawrence, and Bouvier all converge on the same two-clause formulation — decisions of the senate, concerned with particular persons only. There is no evolution or dispute across these sources.
Rapalje & Lawrence adds modest value by pairing the entry with seneschal in a way that suggests alphabetical compression rather than conceptual connection, but the substantive definition is identical to the others. None of the four dictionaries elaborates on the distinction from senatus consulta, the procedural mechanics by which decreta were issued, or their place within the Roman hierarchy of legal sources. Researchers seeking fuller treatment must look beyond dictionary sources to civil law treatises — particularly those of the institutional tradition (Gaius, Justinian's Institutes) — or to modern Roman law scholarship.
The brevity of these entries is appropriate to their function: senatus decreta is a term of art with a fixed meaning, not a concept requiring extensive doctrinal unpacking at the dictionary level. That said, the dictionaries' silence on the consulta/decreta distinction is a genuine gap for anyone using these sources as a first point of reference.