Pro Caelio is a speech given on 4 April 56 BC, by the famed Roman orator Marcus Tullius Cicero in defence of Marcus Caelius Rufus, who had once been Cicero's student but more recently was a political rival. Cicero's reasons for defending Caelius are uncertain, but various theories have been postulated. The speech is regarded as one of the best examples of Roman oratory known and has been so regarded throughout history. It is noteworthy as a prime example of Ciceronian oratorical technique. Caelius was charged with vis (political violence), one of the most serious crimes in Republican Rome. Caelius' prosecutors, Lucius Sempronius Atratinus, Publius Clodius (it has been suggested to be Publius Clodius Pulcher, but it was more likely a freedman or relative), and Lucius Herennius Balbus, charged him with the following crimes: Inciting civil disturbances at Naples; Assault on the Alexandrians at Puteoli; Damage to the property of Palla (about which we know little to nothing); Taking gold for the attempted murder of Dio of Alexandria, then attempted poisoning of Clodia; and The murder of Dio. Caelius spoke first in his own defense and asked Marcus Licinius Crassus to defend him during the trial. Cicero's speech was the last of the defense speeches. The magistrate Gnaeus Domitius presided over the trial. Background and trial Marcus Caelius Rufus was born in 88 or 87 BC, at Interamnia in Picenum, where his father was categorised as a member of the eques (knight) class, a wealthy middle class placed just below the patrician upper class. From 73 to 63 BC, Caelius served a political apprenticeship under Crassus and Cicero. Throughout that apprenticeship, he became familiar with life in the Roman Forum. In 63 BC, Caelius turned his back on Cicero to support Catiline, who was running for consulship. It is unclear whether or not Caelius supported Catiline after the latter had lost the election and taken up arms, but he was not among the people prosecuted for their involvement in the conspiracy. From 62 to 60, Caelius left Rome to serve with the governor of Africa, Quintus Pompeius Rufus. As a young man, that was a very good opportunity for Caelius to see the world and make a little money. However, Caelius still wanted to make a name for himself in Rome, and in April 59 BC, he brought prosecution against Gaius Antonius Hybrida, Cicero's colleague in the consulship of 63