According to Cicero, Praetor was a title which designated the consuls as the leaders of the armies of the state; and he considers the word to contain the same elemental parts as the verb praeire. The period and office of the command of the consuls might appropriately be called Praetorium. Praetor was also a title of office among the Latins: and it is the name which Livy gives to the strategus of the Achaeans.
The first praetor specially so called was appointed in the year 356 BC, and he was chosen only from the Patricians, who had this new office created as a kind of indemnification to themselves for being compelled to share the consulship with the Plebeians. No Plebeian praetor was appointed till the year 337 BC. The Praetor was called collega consulibus, and was elected with the same auspices at the Comitia Centuriata. The consuls were elected first, and then the praetors.
The Praetorship was originally a kind of third consulship, and the chief functions of the praetor were a portion of the functions of the consuls, who according to Cicero, were also called judices a judicando. The praetor sometimes commanded the armies of the state; and while the consuls were absent with the armies, he exercised their functions within the city. He was a Magistratus Curulis and he had the Imperium, and consequently was one of the Magistratus Majores: but he owed respect and obedience to the consuls. His insignia of office were six lictors. At a later period the Praetor had only two lictors in Rome. The praetorship was at first given to a consul of the preceding year as appears from Livy. L. Papirius was praetor after being consul.
In the year 246 BC another Praetor was appointed, whose business was to administer justice in matters in dispute between peregrini, or peregrini and Roman citizens; and accordingly he was called Praetor Peregrinus. The other Praetor was then called Praetor Urbanus "qui jus inter cives dicit," and sometimes simply Praetor Urbanus and Praetor Urbis. The two Praetors determined by lot which functions they should respectively exercise. If either of them was at the head of the army, the other performed all the duties of both within the city. Sometimes the military imperium of a Praetor was prolonged for a second year. When the territories of the state were extended beyond the limits of Italy, new praetors were made. Thus two praetors were created 227 BC, for the administration of Sicily and Sardinia, and two more were added when the two Spanish provinces were formed 197 BC. When there were six praetors, two stayed in the city, and the other four went abroad. The Senate determined their provinces, which were distributed among them by lot. After the discharge of his judicial functions in the city, a Praetor often had the administration of a province with the title of Propraetor, and sometimes with the title of Proconsul. Sulla increased the number of Praetors to eight, which Julius Caesar raised successively to ten, twelve, fourteen, and sixteen. Augustus after several changes fixed the number at twelve. Under Tiberius there were sixteen. Two praetors were appointed by Claudius for matters relating to Fideicommissa, when the business in this department of the law had become considerable, but Titus reduced the number to one; and Nerva added a Praetor for the decision of matters between the Fiscus and individuals.
Marcus Aurelius, according to Capitolinus (M. Ant. c10), appointed a Praetor for matters relating to tutela, which must have taken place after Pomponius wrote. [PANDECTAE.] The main duties of the Praetors were judicial, and it appears that it was found necessary from time to time to increase their number, and to assign to them special departments of the administration of justice.
Sometimes, extraordinary duties were imposed on them, as in the case of the Praetor Peregrinus (144 BC) who was commissioned by a Senatusconsultum to look after the repair of certain aqueducts and to prevent the improper use of the water.
The Praetor Urbanus was specially named Praetor, and he was the first in rank. His duties confined him to Rome, as is implied by the name, and he could only leave the city for ten days at a time. It was part of his duty to superintend the Ludi Apollinares. He was also the chief magistrate for the administration of justice, and to the Edicta of the successive praetors the Roman Law owes in a great degree its development and improvement. Both the Praetor Urbanus and the Praetor Peregrinus had the Jus Edicendi, and their functions in this respect do not appear to have been limited on the establishment of the imperial power, though it must have been gradually restricted as the practice of Imperial Constitutions and Rescripts became common. The limits of these two praetors' administration was expressed by the term Urbanae Provinciae.
The chief judicial functions of the Praetor in civil matters consisted in giving a judex. It was only in the case of Interdicts, that he decided in a summary way. Proceedings before the praetor were technically said to be in jure.
The Praetors also presided at trials of criminal matters. These were the Quaestiones perpetuae, or the trials for Repetundae, Ambitus, Majestas, and Peculatus, which, when there were six praetors, were assigned to four out of the number. Sulla added to these Quaestiones those of Falsum, De Sicariis et Veneficis, and De Parricidis, and for this purpose he added two or according to some accounts four praetors, for the accounts of Pomponius and of other writers do not agree on this point. On these occasions the Praetor presided, but a body of judices determined by a majority of votes the condemnation or acquittal of the accused.
The Praetor when he administered justice sat on a sella Curulis in a Tribunal, which was that part of the Court which was appropriated to the Praetor and his assessors and friends, and is opposed to the Subsellia, or part occupied by the Judices, and others who were present. But the Praetor could do many ministerial acts out of court, or as it was expressed e plano, or ex aequo loco, which terms are opposed to e tribunali or ex superiore loco: for instance, he could in certain cases give validity to the act of manumission when he was out of doors, as on his road to the bath or to the theatre.
A person who had been ejected from the senate could recover his rank by being made Praetor. Sallust was made praetor by this method.
The Praetors existed with varying numbers to a late period in the Empire.