Plutarch Bona Dea Scandal
The story of Clodius, Caesar, and the Bona Dea Scandal in Plutarch comes from section 9 of Plutarch's Life of Caesar. In this, Clodius attends the women-only December feast of the Bona Dea which is being held at the home of Caesar and hosted by his wife Pompeia, thought to have been having an affair with Clodius. A roughly 30-year-old Clodius shows up dressed in women's garb, although presumably not the diaphonous flute-girl garb, looking so much like a woman that he passes until he opens his mouth. As a result of his intrusion, the sacred rites of the Vestal Virgins are violated and it is held to be a sacrilege landing Clodius on trial facing Cicero. Although Clodius is acquitted and Caesar doesn't actually accuse his wife of adultery, Caesar divorces Pompeia because, he says, Caesar's wife must be above suspicion.
In "The Early Career of P. Clodius Pulcher: A Re-Examination of the Charges of Mutiny and Sacrilege," by David Mulroy (Transactions of the American Philological Association (1974-), Vol. 118. (1988), pp. 155-178.) Mulroy argues that Clodius was doing little more than party-crashing when he attended the festival. The sacrificial rite was not a necessary part of the event, which may have been a Bacchanalian festival, for which transvestism would have been appropriate, so Clodius may not have known that he was committing sacrilege. Cicero claims the Bona Dea festival was a revered ancient festival, but there is reason to think it was imported from the Greeks after the fall of Tarentum in 272 B.C., making it 210 years-old at the time of the scandal.