Maenius was appointed in reaction to the discovery of a conspiracy amongst the nobles of Capua against Rome, led by the two brothers Ovius and Novius Calavius.
However as Maenius and Foslius were about to commence the investigation into the conspiracy, Ovius and Novius Calavius both took their own lives, likely due to the consequences of inevitably being found guilty by the Romans.
After the death of the Calavii, Maenius retained his position of dictator alongside Foslius, and using the pretense of uprooting conspiracies against the state, the two began to investigate corruption among the Roman elites.
In reaction to this accusation, both Maenius and Foslius resigned from their positions so that they might be tried and found innocent as private citizens, thus clearing their names, rather than hide from trial behind their offices.
In the dictatorship of Poetelius, he recaptured the city of Fregellae and took Nola, however Foslius is not mentioned as taking part in these events, meaning that he either served as an entirely subordinate officer on campaign or he remained in Rome to handle civil affairs.