[2] In 78 BC, he was consul with Marcus Aemilius Lepidus, who after the death of Sulla proposed the overthrow of his constitution, the re-establishment of the distribution of grain, the recall of the banished, and other measures in the populares spirit.
In 67 and 66 Catulus unsuccessfully opposed the Gabinian and Manilian laws which he viewed as prejudicial to constitutional freedom because they conferred special powers upon Pompey.
Caesar, in return, accused him of embezzling public money during the reconstruction of the temple on the Capitol, and proposed to obliterate his name from the inscription and deprive him of the office of commissioner for its restoration.
Although not a man of great abilities, Catulus exercised considerable influence through his political consistency and his undoubted solicitude for the welfare of the state.
Catulus's great-grandson was the emperor Galba, whom Suetonius claims was extremely proud of his ancestry: "Nero was succeeded by Galba, who was related in no degree to the house of the Caesars, although unquestionably of noble origin and of an old and powerful family; for he always added to the inscriptions on his statues that he was the great-grandson of Quintus Lutatius Catulus Capitolinus.