Roman orator and politician whose attempts, as tribune of the plebs, to enact reforms against the wishes of the Senate led to his downfall and the restriction of the powers of the tribunes.

In order to qualify for the tribunate, Sulpicius had to renounce his patrician status. Elected to this office for 88 BC, he introduced several laws: (1) to distribute among the 35 tribes freedmen and the Italians newly enfranchised as a result of the Social War; (2) to unseat all senators who were more than 2,000 denarii in debt; (3) to recall all men exiled without proper trial; and (4) to transfer the command in the war against Mithradates VI of Pontus from Lucius Cornelius Sulla, the Senate's nominee, to Gaius Marius.

Sulpicius probably wanted chiefly to champion the new Italian citizens, but to do this he needed broad support. Hence, his other three measures were designed to obtain the backing of Marius and of the privileged equites class. Sulpicius is said to have organized a group of 100 young equites and a large bodyguard of 3,000 armed men; violence broke out in the Forum between these forces and the senatorial faction.

After the measures were passed, the consul Sulla, who had headed an army in Campania, marched on Rome and took the city. Marius and Sulpicius fled and were declared outlaws. Sulpicius was caught and killed at Lavinium. His laws were declared “passed by force,” hence invalid. Although his enemies depicted him as a revolutionary demagogue, he may have been a moderate reformer forced (as Cicero implies) by circumstances to go to greater lengths than he had originally intended. He was renowned for his oratory, but his speeches have not been preserved.