4. A lex is that which was enacted by the Roman people on its being proposed by a senatorian magistrate, as a consul. A plebiscitum is that which was enacted by the plebs on its being proposed by a plebeian magistrate, as a tribune.
The plebs differ from the people as a species from its genus, for all the citizens, including patricians and senators, are comprehended in the populi (people); but the plebs only included citizens [who were] not patricians or senators. Plebiscita, after the Hortensian law had been passed, began to have the same force as leges.
5. A senatusconsultum is that which the senate commands or appoints: for, when the Roman people was so increased that it was difficult to assemble it together to pass laws, it seemed right that the senate should be consulted in place of the people.
6. That which seems good to the emperor has also the force of law; for the people, by the Lex Regia, which is passed to confer on him his power, make over to him their whole power and authority. Therefore whatever the emperor ordains by rescript, or decides in adjudging a cause, or lays down by edict, is unquestionably law; and it is these enactments of the emperor that are called constitutiones.
Of these, some are personal, and are not to be drawn into precedent, such not being the intention of the emperor. Supposing the emperor has granted a favor to any man on account of his merit, or inflicted some punishment, or granted some extraordinary relief, the application of these acts does not extend beyond the particular individual. But the other constitutiones, being general, are undoubtedly binding on all.
7. The edicts of the praetors are also of great authority. These edicts are called the ius honorarium, because those who bear honors [i.e., offices] in the state, that is, the magistrates, have given them their sanction. The curule aediles also used to publish an edict relative to certain subjects, which edict also became a part of the ius honorarium.
Interpret publicly
8. The answers of the jurisprudenti are the decisions and opinions of persons who were authorized to determine the law. For anciently it was provided that there should be persons to interpret publicly the law, who were permitted by the emperor to give answers on questions of law. They were called jurisconsulti; and the authority of their decision and opinions, when they were all unanimous, was such, that the judge could not, according to the constitutiones, refuse to be guided by their answers.
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