Hadith.5142 - Imam Jafar ibn Muhammad Al-Sadiq (as) was asked about a man who said to a woman, "O' adulteress," and she replied: "You are more adulterous than me."
Imam (as) said: "She is subject to the legal punishment (hadd) for the accusation she made against him. However, regarding her self-admission, she is not to be punished unless she confesses to that before the Imam four times."