Definition
Honorarium jus (Latin) is a term from Roman law referring to the body of law created by the praetors through their edicts, together with the edicts of the aediles. It stands in contrast to the ius civile — the ancient, formal civil law of Rome derived from legislation, custom, and juristic interpretation — and represents the flexible, magistrate-made layer of the Roman legal order. The praetors, as senior Roman magistrates with jurisdictional authority, issued annual edicts announcing the remedies and procedural rules they would apply during their term of office. Over time, these edicts accumulated into a substantial body of rules that filled gaps in and effectively modified the older civil law. The aediles, who had jurisdiction over markets, public spaces, and certain commercial transactions, contributed their own edicts, particularly regarding the sale of slaves and animals. Together, this magistrate-generated law formed the honorarium jus — so named because the praetors and aediles held positions of honor (honores) in the Roman state.
Common Confusion
Honorarium jus is sometimes loosely equated with the ius praetorium alone. While the praetorian edict is the dominant component, the term technically encompasses the aedilician edicts as well. Researchers should also take care not to conflate honorarium jus with the broader concept of ius honorarium, which is the more commonly encountered Latin form of the same concept in modern Roman law scholarship. The two forms refer to the same body of law; the inversion of terms in older English-language legal dictionaries reflects variation in Latin usage rather than any substantive distinction.
Why It Matters in Research
This term appears almost exclusively in historical and Roman law contexts. Researchers encountering it in nineteenth- or early-twentieth-century legal sources — particularly in treatises on civil law, comparative law, or equity jurisprudence — should understand it as a technical Roman law category, not a concept operative in any modern common law or civil law jurisdiction.
The term carries navigational value for two reasons. First, it connects Roman law to the development of equity in common law systems. Scholars and legal historians drew explicit analogies between the praetor's equity-like power to override rigid civil law rules and the English Chancellor's equitable jurisdiction. Sources discussing the origins of equity frequently invoke honorarium jus or ius honorarium as a Roman antecedent. Second, the concept illuminates the structure of Roman law as a dual system — formal civil law alongside magistrate-made law — a framework that shaped the later compilation of Justinian's Corpus Juris Civilis, which itself forms the foundation of modern civil law systems.
Researchers working in comparative law, legal history, or the history of equity should expect to encounter this term in treatises by Gaius, Papinian, and later civilian commentators, as well as in nineteenth-century English and American scholars writing on Roman law's influence.
Historical Dictionary Support
Both editions of Black's Law Dictionary provide a minimal but consistent definition: the law of the praetors and the edicts of the aediles. The first and second editions are nearly identical in substance, suggesting no meaningful evolution in how the term was understood within the English-language legal dictionary tradition.
What the historical dictionaries do not provide is context for why this body of law was called honorarium — a gap significant for researchers. The name derives from honores, the Roman term for public magistracies held as positions of civic honor rather than professional employment. The praetor and aedile held their offices as civic duties, and the law they created took its name from that status. Black's entries omit this derivation entirely, which can leave researchers without the conceptual anchor needed to understand related Roman law terminology.
The historical dictionaries also make no mention of the eventual codification of the praetorian edict under Hadrian (attributed to the jurist Julian, c. 130 CE), which effectively froze the living, evolving honorarium jus into a fixed text. This development is essential background for any serious engagement with Roman law sources.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Roman Law; Equity — Historical Development; Ius Civile.