A Career in Law
There were a number of courts (quaestiones) set up at Rome to hear particular charges and crimes of frequent occurrence. These included courts for charges of maiestas (treason), ambitus (bribery at elections), repetundae (extortion by provincial governor), veneficia (poisoning) and peculatus (theft of property). Magistrates (praetors) were in charge of each court. There was no public prosecutor at Rome. It was up to private citizens to request authority from the magistrate in charge of the particular court to bring a prosecution.
The authorised accuser presents his indictment in writing (nomen deferre) to the magistrate who enters the charge in the official record (nomen recipere). The magistrate interrogates the accused, and unless the accused pleads guilty, fixes a date for the hearing.
The jury (75 for repetundae and maiestas, 51 for crimes of assasination) is chosen by lot from panels of 300 (decuriae), composed of senators, Equites and tribuni aerarii (similar class to Equites, but less wealthy.)
Both the prosecution and the defence have a limited right of challenging the composition of the jury.
The trial takes place in public, in the Forum. The accused must be present to be prosecuted.
At the end of the trial, the jury gives its verdict by majority' vote. The presiding magistrate (praetor) does not have a vote, but pronounces judgement and sentence, against which there is no appeal. if the accused is sentenced to death, this can be avoided by voluntary exile.
Cicero's Pro Caelio
This trial is held in the quaestio inter veneficos et sicarios (the court for poisoners and assassins). Caelius is accused under the lex Lutatia de vi (a law on violence). The charges Cicero defends are two - (a) that Caelius has stolen gold from his ex-girifriend, Clodia; (b) that Caelius has attempted to murder Clodia with poison.
The principal prosecutor is Lucius Sempronius Atratinus. The subscriptores (seconders) are Publius Clodius and Lucius Herennius Balbus. Cicero, the defence council, is supported by Crassus, who has earlier dealt with three of the five counts against Caelius.