On May 20, 1968, the Supreme Court ruled for the first time in Duncan v. Louisiana that in all cases involving serious crime the states must provide trial by jury. Prior to this decision, the Sixth Amendment guarantee was held to apply only to trials in federal courts. Two years later, on June 22, 1970, the high tribunal addressed itself in Baldwin v. New York and Williams v. Florida to some questions unanswered by the Duncan case: a “serious” crime, it announced, was one for which a penalty of over six months imprisonment could be imposed; and a six-member jury would pass constitutional muster. Still unanswered after Williams and Baldwin is the question of the constitutionality of less than unanimous verdicts and of juries composed of fewer than six members. These and other questions will be discussed later in this Article after a consideration of the “incorporation theory” or the applicability of the Bill of Rights to the states.