Lex Gellia Cornelia was a law passed in 72 BC after a proposal of the consuls Lucius Gellius Poplicola and Gnaeus Cornelius Lentulus Clodianus, that gave Pompey the power of granting citizenship to valuable soldiers.
Here are the passage in which Cicero mentions the law:Nascitur, iudices, causa Corneli ex ea lege, quam L. Gellius Cn.
Cornelius ex senatus sententia tulerunt; qua lege videmus ita esse sanctum, ut cives Romani sint ii, quos Cn.
Pompeius de consilii sententia singillatim civitate donaverit.
"What has given rise to the case of Cornelius, gentlemen, is a law which Lucius Gellius and Gnaeus Cornelius carried, in accordance with a resolution of the Senate; and we see that by this law it was enacted that those on whom Gnaeus Pompeius, with the concurrence of his advisers, conferred Roman citizenship individually, should be Roman citizens."