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How did Roman emperors become the main source of legislation?
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Legislation
Former U.S. president Harry S. Truman (right) looking on as U.S. Pres. Lyndon B. Johnson signs the Medicare bill at the Harry S. Truman Library and Museum in Independence, Missouri, July 30, 1965.
The transition of Roman emperors into the primary source of legislation was a gradual process that shifted power away from traditional republican institutions toward autocratic rule.
Initially, early emperors maintained the appearance of republican governance by using the Senate as their mouthpiece, issuing laws through senatorial decrees. However, by the 2nd century CE, this dynamic had fundamentally changed:
- Erosion of Assemblies and Senate: After 100 CE, popular assemblies ceased to meet to pass laws. The Senate increasingly functioned as a rubber stamp, often repeating the emperor's speeches verbatim rather than exercising independent legislative authority.1
- Imperial Enactments: Emperors began legislating directly through constitutiones principum, which included edicta (proclamations), mandata (instructions to officials), rescripta (written legal answers), and decreta (judicial decisions).21
- Legal Precedence: By the time of the Antonine emperors, legal scholars established that whatever the emperor ordered was legally binding. Furthermore, the emperor gained exclusive control over modifying the edictum perpetuum, effectively ending the ability of magistrates to alter law through their own interpretations.1
- Consolidation: By 200 CE, the emperor had largely replaced all other sources of written law. This centralization of power paved the way for the later dominate period, where the emperor’s will was the undisputed source of law, eventually leading to the comprehensive codifications under Justinian I.13