was tribune of the plebs in B. C. 56, when he brought in a bill for Cicero's recall from exile. (Cic. Post. Red. in Sen. 8.) In the same year the Messian law, by the same tribune, assigned extraordinary powers to Cn. Pompey (id. ad Att. 4.1.) Cicero defended Messius when he was recalled from a legatio, and attacked by the Caesarian party (id. ad Att. 4.15, 8.11). Messius afterwards appears as an adherent of Caesar's, whose troops he introduced into Acilla, a town in Africa. (Caes. B. A. 33.) Messius was aedile, but in what year is unknown.