Moral turpitude is a legal concept in the United States and prior to 1976, Canada, that refers to "an act or behavior that gravely violates the sentiment or accepted standard of the community". This term appears in U.S. immigration law beginning in the 19th century. The concept of "moral turpitude" might escape precise definition, but it has been described as an "act of baseness, vileness, or depravity in the private and social duties which a man owes to his fellowmen, or to society in general, contrary to the accepted and customary rule of right and duty between man and man."