In December 1976, the California state supreme court ruled that the California death penalty statute, which then required a mandatory death penalty for certain categories of murder, was unconstitutional in view of the U.S. Supreme Court's recent rulings in Gregg v. Georgia and other cases.Rockwell v. Superior Ct., 18 Cal. 3d 420 (Cal. 1976). As a result, California prisoners sentenced to death under the unconstitutional statute, including Riley, could not be executed. Riley's sentence was changed from death to two concurrent life sentences with the possibility of parole after 7 years. While in prison, Riley lost weight, received his high school diploma, and earned the equivalent of a college degree.
