Roman Law: The Legal Foundation of the Western World

Almost every legal system in the modern West is built, in part, on the law of ancient Rome. The Roman concepts of contract, of property, of marriage, of citizenship, of corporations, of court procedure, and of written statutes are still recognizable in the civil codes of France, Germany, Italy, Spain, and the Latin American republics. The Scottish and English common-law systems have inherited less of the Roman tradition, but the basic institutions of trial by judge, the rules of evidence, and the binding force of precedent are all products of the Roman legal system. The philosopher of law Sir Henry Maine famously said that the great movement of the modern world had been “from status to contract” — a movement whose starting point was Roman law. For the broader context, see Roman Society and Daily Life.

The Roman law of the late Republic and the empire was a remarkably sophisticated body of rules, and it was the work of more than a thousand years of development. It began with the Twelve Tables of 451 BCE, was developed by the praetors of the Republic, was refined by the great jurists of the second and third centuries CE, was adapted by Diocletian and Constantine to the needs of the late empire, and was finally collected and codified by the emperor Justinian in the Corpus Juris Civilis of 534 CE. The texts of Justinian’s code are still the basis of law in many countries of the modern world.

The Twelve Tables

The first written law of Rome was the Law of the Twelve Tables, traditionally drafted in 451 – 450 BCE by a commission of ten magistrates, the Decemviri. The Twelve Tables were inscribed on twelve bronze tablets and posted in the Roman Forum, where they could be read by all citizens. Almost nothing of the original survives — the tablets were destroyed in the Gallic sack of Rome in 390 BCE — but the text was widely quoted by later jurists, and the substance of many of its provisions can be reconstructed.

The Twelve Tables dealt with the law of procedure, the family, inheritance, property, and criminal law. Some of its provisions are startling in their severity: a creditor could sell an insolvent debtor into slavery, an adulterous wife could be killed by her husband, and a child who had struck his father could be put to death. Other provisions, however, are recognizably modern: a contract had to be honored, a thief was liable for double the value of what he stole, a court order had to be enforced. The Twelve Tables established the principle that the law should be written and public, and that the citizen had a right to know it.

The Ius Civile and the Ius Gentium

The Roman law of the Republic was divided into two main bodies. The ius civile was the law of the Roman citizen, applying only to those who held Roman citizenship. It was the older law, derived from the Twelve Tables and from the statutes, the leges, passed by the popular assemblies. The ius gentium was the law of the peoples, the body of rules that applied to all the peoples of the empire, Roman and non-Roman alike. The ius gentium was developed through the edicts of the praetor and the rulings of the great jurists, and it included many principles borrowed from Greek, Etruscan, and provincial practice.

The distinction between the ius civile and the ius gentium was eventually abolished. In 212 CE the emperor Caracalla issued the Constitutio Antoniniana, extending Roman citizenship to nearly every free inhabitant of the empire. From that point on, there was only one Roman law for nearly all the people, and the ius gentium was simply the ius civile applied to everyone. The legal consequences of Caracalla’s grant were profound. The Church Father Tertullian complained that the world had become a single city of Roman citizens.

The Praetor’s Edict

The most important engine of legal change in the Roman Republic was the praetor, the senior magistrate of the city of Rome. The praetor issued an annual edict at the beginning of his term, in which he set out the rules of procedure that he would follow during the year. The edict was binding on the praetor for the year, and successive praetors tended to follow the rules of their predecessors, with modifications. The cumulative effect of the edicts over centuries was a body of law that was at once flexible and consistent, adapted to new circumstances while preserving the principles of older practice.

The most famous of the praetorian edicts was the Edictum Perpetuum, the “perpetual edict” issued by the jurist Salvius Julianus under the emperor Hadrian in about 130 CE. The Edictum Perpetuum, as the name suggests, was meant to be permanent. The edict fixed the law of the praetor once and for all, and successive praetors were no longer free to modify it. The edict did not end the development of Roman law, but it ended the development of the praetorian edict, and from that point on the great jurists and the imperial constitutions took over the work of legal change.

The Formulary System

The procedure of the Roman civil trial of the late Republic and the early empire was based on a formulary system, a process in which the issues between the parties were reduced to a written set of formulae. The case was heard in two stages. The first stage, in iure, was heard before the praetor, who determined the legal issues and drew up the formulae. The second stage, apud iudicem, was heard before a private judge, the iudex, who applied the formulae to the facts. The system gave Roman civil procedure its remarkable flexibility and contributed to the development of legal science.

The formulary system was eventually replaced by the cognitio extra ordinem, the “extraordinary procedure” introduced by the emperors of the later second century. Under the new system, cases were heard by imperial officials, not by private judges, and the procedure was more bureaucratic and less flexible. The cognitio procedure was the ancestor of the modern continental trial.

The Jurists

The great period of Roman legal science was the late first to the early third century CE, when a succession of great jurists — legal scholars, judges, and imperial advisers — developed the principles of the law into a sophisticated system. The first of the great jurists was Gaius, who wrote the Institutes, a textbook of Roman law, in the second century. The Institutes is the only classical Roman legal text that has survived in something like its original form, and it was the model for the Institutes of Justinian six centuries later.

The second great generation of jurists was the generation of Papinian, Ulpian, Paul, and Modestinus, who wrote under the emperor Septimius Severus and his successors. Aemilius Papinianus, the praetorian prefect of Severus, was the greatest of the Roman jurists, and his work became the foundation of later Roman law. Domitius Ulpianus, the praetorian prefect of Alexander Severus, was the most prolific; he wrote more than six hundred books, and his opinions are cited more than a thousand times in the Digest of Justinian. Julius Paulus and Herennius Modestinus completed the great age of Roman legal science. The classical jurists were a tightly closed group: the emperor authorized certain jurists to give binding legal opinions to judges, and the body of opinion of these men was treated as law.

In 426 CE the emperor Theodosius II issued the Law of Citations, which named five jurists — Gaius, Papinian, Ulpian, Paul, and Modestinus — as the only ones whose opinions were to be cited as authority. The Law of Citations remained in force for a thousand years.

Citizenship

Roman citizenship was the cornerstone of the Roman legal system, and the gradual extension of citizenship across the empire was the most important development in the law of the imperial period. The original citizen body was limited to the patrician and plebeian families of Rome itself, but it was extended over the centuries through the grants to allied Italian cities, the formal enfranchisement of all Italy after the Social War of 91 – 88 BCE, and the long slow extension of citizenship across the western and eastern provinces. Julius Caesar and Augustus were both generous in granting citizenship to individuals, and the Constitutio Antoniniana of 212 CE completed the process.

A Roman citizen had a set of legal rights that were not shared by non-citizens. He could appeal a criminal sentence to the emperor. He could make a legal will and have it executed throughout the empire. He could marry a Roman citizen and have children with full legal status. He could sue and be sued in the Roman courts. He could hold a Roman public office, although the higher offices of the imperial government were reserved for citizens of free birth and senatorial rank. Citizenship was hereditary, and a citizen’s son was a citizen. Citizenship could be lost, although in the imperial period this was rare; the Cincian Law of 204 BCE had restricted the categories of citizens who could be punished by loss of citizenship.

The Influence of Christianity

The conversion of Constantine the Great to Christianity in 312 CE and the legal establishment of Christianity under Theodosius I in 380 CE transformed the substance of Roman law as well as its form. The Christian emperors added new categories of law: laws against pagan worship, laws for the protection of the church and the clergy, laws for the regulation of marriage and the family, laws for the suppression of heresy, and laws for the protection of the poor and the slave. The bishops of the church became an important arm of the imperial government, and the episcopal courts heard many disputes in the later empire.

Christianity also changed the spirit of Roman law. The classical jurists had been Stoics, and they had been willing to recognize suicide, abortion, exposure of infants, and the killing of slaves. The Christian emperors made all of these crimes, although the prohibitions were not always enforced. The classical jurists had been tolerant of same-sex relations between free men; the Christian emperors made them crimes, at least in theory. The classical jurists had assumed the legality of slavery; the Christian emperors added the principle that a slave had a soul and that his master had a duty to treat him as a fellow Christian.

The Christianization of the law reached its peak in the legislation of Theodosius II in 438 CE, the Codex Theodosianus, the first official collection of imperial constitutions. The Theodosian Code, in sixteen books, was the model for the later collections of Justinian and the foundation of medieval canon law.

The Corpus Juris Civilis

The last great work of Roman law was the Corpus Juris Civilis of the emperor Justinian I, compiled in Constantinople in 529 – 534 CE. The Corpus was a collection of four works: the Codex, a compilation of imperial constitutions from Hadrian to Justinian; the Digest (Pandectae), a digest of the writings of the classical jurists; the Institutes, an introductory textbook modeled on the Institutes of Gaius; and the Novellae, the new laws issued by Justinian after the compilation. The work was enormous: the Digest alone contains more than nine thousand texts and runs to more than 1.5 million words.

The Digest was the most important and the most difficult part. It was compiled in three years by a commission of sixteen jurists led by Tribonian, the quaestor of the sacred palace. The compilers combed the writings of the classical jurists, selected what was still valid, edited it to remove contradictions, and arranged the resulting material under fifty books. The work was so successful that the Digest became the foundation of continental legal education for a thousand years. The glossators of the eleventh and twelfth centuries, working in Bologna, recovered the text of the Digest and built around it an entire legal science.

The legacy of the Corpus Juris Civilis is still with us. The civil codes of France (1804), Germany (1900), Italy (1942), Spain, Portugal, the Netherlands, much of Latin America, and the modern state of Louisiana are all ultimately based on Justinian’s compilation. The vocabulary of the modern civil law — the distinction between ius and lex, between public and private law, between contract and tort, between the rights of the citizen and the powers of the state — is the vocabulary of the Roman jurists, preserved across two millennia.