Born in Scranton, North Dakota, the son of Ernest Christopher, a bank manager, and his wife Catherine, Christopher graduated from Hollywood High School, and attended the University of Redlands, before transferring to the University of Southern California. He was a member of the college fraternity Kappa Sigma Sigma. He graduated magna cum laude from the University of Southern California in February 1945. From July 1943 to September 1946, he served in the United States Naval Reserve, with active duty as an ensign in the Pacific Theater. He attended Stanford Law School from 1946–1949, where he was the founder and President of the Stanford Law Review and was elected to the Order of the Coif.