One-third were to be senators, and two-thirds men of equestrian census, one-half of whom must have been tribuni aerarii, a body as to whose functions there is no certain evidence, although in Cicero's time they were reckoned by courtesy amongst the equites. In 66 BC, Cotta and Lucius Manlius Torquatus accused the consuls-elect, Publius Cornelius Sulla and Publius Autronius Paetus, for the following year of bribery in connection with the elections; they were condemned, and Cotta and Torquatus chosen in their places. Year after his consulship, in 64 BC, he was elected censor, but he and his colleague abdicated on account of the machinations of the tribunes..
After the suppression of the Catilinarian conspiracy, Cotta proposed a public thanksgiving for Cicero's services, and after the latter had gone into exile, supported the view that there was no need of a law for his recall, since the law of Clodius was legally worthless.
He subsequently attached himself to Caesar, and it was currently reported that Cotta (who was then quindecemvir) intended to propose that Caesar should receive the title of king, it being written in the sibylline oracles that the Parthians could only be defeated by a king. Cotta's intention was not carried out in consequence of the murder of Caesar, after which he retired from public life.