Indian Penal Code, 1860
497. Adultery
Whoever has sexual intercourse with a person who is and whom he
knows or has reason to believe to be the wife of another man, without the
consent or connivance of that man, such sexual intercourse not amounting to the
offence of rape, is guilty of the offence of adultery, and shall be punished
with imprisonment of either description for a term which may extend to five
years, or with fine, or with both. In such case the wife shall be punishable as
an abettor.