Vir clarissimus

The Senate of the Roman Republic was a political institution in the ancient Roman Republic. It was not an elected body, but one whose members were appointed by the consuls, and later by the censors. After a Roman magistrate served his term in office, it usually was followed with automatic appointment to the Senate. According to the Greek historian Polybius, our principal source on the Constitution of the Roman Republic, the Roman Senate was the predominant branch of government. Polybius noted that it was the consuls (the highest-ranking of the regular magistrates) who led the armies and the civil government in Rome, and it was the Roman assemblies which had the ultimate authority over elections, legislation, and criminal trials. However, since the Senate controlled money, administration, and the details of foreign policy, it had the most control over day-to-day life. The power and authority of the Senate derived from precedent, the high caliber and prestige of the senators, and the Senate's unbroken lineage, which dated back to the founding of the Republic in 509 BC.

Originally the chief-magistrates, the consuls, appointed all new senators. They also had the power to remove individuals from the Senate. Around the year 318 BC, the "Ovinian Plebiscite" (plebiscitum Ovinium) gave this power to another Roman magistrate, the censor, who retained this power until the end of the Roman Republic. This law also required the censors to appoint any newly elected magistrate to the Senate. Thus, after this point in time, election to magisterial office resulted in automatic Senate membership. The appointment was for life, although the censor could impeach any senator.

The Senate directed the magistrates, especially the consuls, in their prosecution of military conflicts. The Senate also had an enormous degree of power over the civil government in Rome. This was especially the case with regards to its management of state finances, as only it could authorize the disbursal of public monies from the treasury. In addition, the Senate passed decrees called senatus consultum, which was officially "advice" from the Senate to a magistrate. While technically these decrees did not have to be obeyed, in practice, they usually were. During an emergency, the Senate (and only the Senate) could authorize the appointment of a dictator. The last ordinary dictator, however, was appointed in 202 BC. After 202 BC, the Senate responded to emergencies by passing the senatus consultum ultimum ("Ultimate Decree of the Senate"), which suspended civil government and declared something analogous to martial law.

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