The Legal Punishment is Implemented Upon the Drunkard Who Commits Illegal Sexual Intercourse
Question :
A man raped his wife's sister while he was drunk. What is the punishment of the Islamic Law for him? And does. this woman who was raped have any right against him? Likewise, I am asking what I must do with this girl after I have made a contract of marriage with her and she informed me of what had happened after three months and I know that she is innocent.
Answer:
The punishment of this man who raped his wife's sister while he was drunk is that the (same) legal punishment for a sober adulterer be inflicted upon him, according to what is well known in the Madhhab of Imam Ahmad. If this man was united with his wife in a valid marriage, and they are both free, rational adults, then he must be stoned to death, because this is the punishment for the married adulterer, as is confirmed in the Two Sahihs from the Hadith of Abu Hurairah and Zaid bin Khalid Al-Juhani, may Allah be pleased with them. That is the story of the servant who committed an act of illegal sexual intercourse with the wife of the man who had hired him, and the Prophet ordered that the woman be stoned.
And it has been confirmed in the Two Sahihs from the Hadith of 'Umar bin Al-Khattab, may Allah be pleased with him, that he delivered a sermon in which he said:
"Verily, stoning is confirmed in the Book of Allah for the one who commits illegal sexual intercourse, if he is a married man or a married woman, if the evidence is produced, or she is pregnant or a confession."
As for the girl who was raped, she has a right upon him according to what is determined by the Islamic Law Court Judge in the matter. As for this man who has married the girl, and then after three months she told him what happed, and he says that he knows she is innocent: If he considers that his wife is righteous and straightforward, he should hold onto her. The rape she suffered should not adversely affect her in any way, because it happened without her consent.
Source:
Ibn 'Uthaimin
Fatawa Islamiyah, Vol. 6 Pages 196-197-198