In 74 BC, he accused his stepfather Statius Albius Oppianicus of an attempt to poison him; had it been successful, the property of Cluentius would have fallen to his mother Sassia.
The defense was undertaken by Cicero; his extant speech Pro Cluentio, written up after the trial, is regarded as a model of oratory and Latin prose.
Cluentius was acquitted and Cicero subsequently boasted that he had thrown dust in the eyes of the jury "...se tenebras iudicibus offudisse in causa Cluenti gloriatus est".
He presents Oppianicus as a monster who killed many members of his own family, Sassia as a stock figure of female wickedness.
Cicero deals at length with earlier verdicts quoted against Cluentius, offers a fairly brief rebuttal of the charge of poisoning and finishes with a rousing peroration.