Hanaway was born in Stevens Point, Wisconsin. He graduated from the University of Wisconsin-Madison School of Commerce in 1958, and received his juris doctor from the University of Wisconsin Law School in 1961. He had previously served in the United States Army from 1954 - 1956.
Before being elected Attorney General, Hanaway served as a Brown County Assistant District Attorney from 1962 - 1964, and later as a special prosecutor in Brown County from 1967 - 1968. He also served concurrently as the De Pere city attorney from 1965 - 1972, and again from 1976 - 1979. In between those stints as city attorney, he served as mayor of De Pere from 1972 - 1974.
Hanaway was elected as a Republican in a special election to the Wisconsin State Senate in July 1979. He was re-elected to the State Senate in 1980, and again in 1984. He served as Assistant Minority Leader from 1981 - 1982.
Hanaway went on to serve as a Brown County Circuit Judge from 1991 until his death in 1995. He and his wife, Jo Ann, had four children.