Gaius Calpurnius Piso was a consul of the Roman Republic. He was consul in 67 BC with Manius Acilius Glabrio. He belonged to the high aristocratic party, and, as consul, led the opposition to the proposed law of the tribuneAulus Gabinius, by which Gnaeus Pompeius Magnus was to be entrusted with extraordinary powers for the purpose of conducting the war against the pirates. The law, however, was carried, notwithstanding all the opposition of Piso and his party. Shortly afterwards, when the orders that Pompeius had issued were not carried into execution in Gallia Narbonensis, in consequence, as it was supposed, of the intrigues of Piso, Gabinius proposed to deprive the latter of his consulship, an extreme measure which Pompey's prudence would not allow to be brought forward. Piso did not have an easy life during his consulship. In the same year the tribune, Gaius Cornelius, proposed several laws, which were directed against the shameless abuses of the aristocracy. All these Piso resisted with the utmost vehemence, and none more strongly than a stringent enactment to put downbribery at elections. But as the senate could not with any decency refuse to lend their aid in suppressing this corrupt practice, they pretended that the law of Cornelius was so severe that no accusers would come forward, and no judges would condemn a criminal. They therefore made the consuls bring forward a less stringent law, imposing a fine on the offender, with exclusion from the senate and all public offices. It was with no desire to diminish corruption at elections that Piso joined his colleague in proposing the law, for an accusation had been brought against him in the preceding year of obtaining by bribery his own election to the consulship. In 66 and 65 BC, Piso administered the province of Gallia Narbonensis as proconsul, and while there, he suppressed an insurrection of the Allobroges. Like the other Roman nobles, he plundered his province, and was defended by Cicero in 63 BC, when he was accused of robbing the Allobroges, and of executing unjustly a Cisalpine Gaul. The latter charge was brought against him at the instigation of Caesar, and Piso, in revenge, implored Cicero, without success, to accuse Caesar as one of the conspirators of Lucius Sergius Catilina. Piso must have died before the outbreak of the civil war, but in what year is uncertain. Cicero ascribes to him considerable oratorical abilities.
