He was born in Chester, South Carolina, the son of John McLure and Helen Witherspoon Hemphill. Educated in Chester public schools, he graduated from the University of South Carolina, receiving an A.B. degree in 1936 and an LL.B. degree in 1938.
He began practice in Chester with his father and uncle, Paul Hemphill. During World War II, he enlisted in the United States Army-Air Force and served, from 1941 until 1945, as a bomber pilot instructor.
He served as a State Representative from 1947 until 1948, and as Solicitor of the Sixth Judicial Circuit from 1951 through 1956. He was a member of the United States House of Representatives from 1957 until 1964, a United States District Judge from 1964 until 1983, and Chief Judge of the District of South Carolina from 1979 to 1980. He also had Senior Status as a District Judge from 1980 until 1983 and Temporary Emergency Court of Appeals from 1981 until 1983.
Robert Hemphill’s activities included being a Sunday School teacher and Elder in the Purity Presbyterian Church in Chester County, South Carolina. He was a member of the American Bar Association, the American Judicature Society, the Civil Air Patrol, the American Legion, the National Lawyers Club, the American Law Institute, and Kappa Alpha fraternity.
A vigorous and able advocate; a wise, independent and human judge; a kind and considerate friend — this was Robert Hemphill.