Roman law, the legal system of Rome from the supposed founding of the city in 753 B.C. to the fall of the Byzantine Empire in A.D. 1453; it was later adopted as the basis of modern civil law. Most authorities, however, disregard the largely static period following the reign of Justinian I (527-65).

Early Roman Law

Roman law in the earliest period known is typically expressed in the Twelve Tables with their marked formalism. The usual early procedure was also stereotyped; it was the legis actio, a form of charge and denial the words of which had to be followed exactly by the parties at the risk of losing the suit. Exact knowledge of the words constituting the legis actiones was limited to a body of patrician priests, the College of Pontiffs. The reduction of these forms to writing (c.250 B.C.) was a victory for the plebeians and a step in reducing the religious and formal element in the law. Soon the primary source of law became the lex (plural leges), a statutory enactment that was proposed by a magistrate and accepted by a popular assembly. Among the assemblies empowered to enact leges was that of the plebeians.

Expansion and Development

In the late 3d cent. B.C., Roman law could no longer limit itself to the inhabitants of the republic but was forced to take account of the surrounding non-Roman peoples. Thus, to the jus civile, which governed relations among the Romans and those admitted to Roman status, was added the jus gentium, the law applied in dealings with a foreigner. The jus gentium incorporated much of the highly developed commercial law of the Greek city-states and of other maritime powers. Such provisions, being better adapted to Rome's expanding economic needs than the unyielding provisions of the jus civile, in time tended to be applied universally.

The development of new principles was especially vigorous after c.100 B.C., an important source being the jus honorarium, i.e., the law of the praetors (chief magistrates). On assuming office the praetor announced the principles, sometimes novel, that would govern his decisions. The praetors also contributed greatly to making practice more flexible. In place of the legis actiones, they often used the formulary system. A formula, like a legis actio, was a device for determining the issue between the parties; but instead of being a mere interchange of prescribed speeches, it provided a structure for discussing the actual dispute. Whichever method was used, when the nature of the dispute was agreed upon, the parties brought their case before the judex, a private functionary, who considered the evidence and gave judgment.

Under the Empire

After the establishment of the empire, the development of law largely passed from the praetors (the practice of issuing new edicts ended c.A.D. 125) and from the popular assemblies into the hands of the emperors, sometimes operating through the senate. Various types of imperial enactments called constitutions were issued in abundance.

Legal problems attained great complexity, and the aid of a specially trained class of scholars was enlisted for their solution. Those jurists with a special license from the emperor could write responsa to guide the judges in deciding cases. Most prominent among the jurists was Papinian; his work, with that of Gaius, Modestinus, Paulus, and Ulpian, attained the highest authority. The employment of jurists was a step in making the whole of Roman procedure official; in this process the institution of judex was abolished and the trial placed entirely in the hands of a judge.

By the early 4th cent. most branches of Roman law were fully developed. The system was generally responsive to legal needs and allowed sufficient variety to meet local customs. A grave disadvantage of the system, however, was that the vast corpus of legal matter included much that was confused, contradictory, or redundant; reduction to code form was required. The Theodosian Code (438), the earliest attempt, was followed by the Breviary of Alaric (506). Finally the task was accomplished with the culminating work of Roman legal scholarship, the Corpus Juris Civilis (completed 535) under the direction of Tribonian.

Continuing Influence

After the mid-6th cent., Roman law persisted as a part of the Germanic laws and was in effect in the Byzantine Empire. Revival of classical studies during the Renaissance prepared the way for the partial resurrection of Roman law as the modern civil law in a large part of the world. The jus gentium is perhaps the most widely represented in modern legal systems, for it is the basis of commercial law even in those countries that follow common law.

Law of the Roman Republic and Empire. Roman law has influenced the development of law in most of Western civilization. It dealt with matters of succession (or inheritance), obligations (including contracts), property (including slaves), and persons. Most laws were passed by assemblies dominated by the patrician families, though the rulings of magistrates were also important. Later emperors bypassed these forms and issued their own decrees. The interpretations of jurists also came to have the weight of law. Though various attempts were made to gather and simplify existing laws (beginning with the Law of the Twelve Tables), by far the most successful effort was that of Justinian I, whose code superseded all previous laws and formed the Roman Empire's legal legacy (see Code of Justinian). Roman legal procedure is the basis for modern procedure in civil-law countries. In the early Republic, the plaintiff was required to call the defendant to court or to bring him by force. A magistrate then decided whether the case should go before a judex, or prominent layman. The judex heard arguments from advocates and questioned witnesses; he made a decision but had no power to execute it. In the later Republic, much greater power was placed in the hands of the magistrates and courts: the summons was issued by the court, the trial was held only before a magistrate, and the court became responsible for the execution of the sentence.

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