Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said that the Prophet (peace and blessings be upon him) was delivering the Friday sermon when a man of Banu Layth bin Bakr came, stepping over the people, until he came close to him and said: "Establish the prescribed punishment on me." He scolded him and made him sit down, but he did the same three times. Then he (peace and blessings be upon him) asked: "For what is the punishment due upon you?" He said: "For adultery." Among his Companions were Sayyiduna Ali, Sayyiduna Abbas, Sayyiduna Zayd bin Harithah and Sayyiduna Uthman (may Allah be pleased with them). He (peace and blessings be upon him) said: "Go and give him a hundred lashes." He was unmarried. It was said to him (peace and blessings be upon him): "O Messenger of Allah, is the prescribed punishment not to be applied to the woman with whom he did this?" So he (peace and blessings be upon him) had him called and asked him about that woman, and he named a woman of Banu Bakr. When that woman was asked, she swore an oath and denied it, and said: "Allah is my witness." Then he (peace and blessings be upon him) asked the man: "Do you have any witness that you did this with her?" He said: "No." So then he (peace and blessings be upon him) had him given eighty lashes as the prescribed punishment for false accusation (qadhf).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحدود / 17003