On June 28, 1984, President Reagan nominated Walter T. Cox III to serve as a Judge of the United States Court of Appeals for the Armed Forces for a term of 15 years. The nomination was confirmed by the Senate on July 26, and on September 6, he was administered the Oath of Office and officially assumed his duties. He became the Chief Judge of the Court on October 1, 1995, and retired in September 1999.

Chief Judge Cox earned his B.S. in Industrial Management from Clemson University in May 1964, where he was also a Cadet-Colonel of the Army ROTC Brigade and a Distinguished Military Graduate. He was commissioned as a regular Army Second Lieutenant in May 1964, and was assigned to the University of South Carolina School of Law on excess leave (1964-1967) where he earned his J.D. degree cum laude, graduating first in his class. He attended the Judge Advocate General's School in Charlottesville, Virginia and the Defense Language Institute, where he learned to speak, read, and write German. Upon graduation, he served as Liaison Officer to the Minister of Justice for the State of Bavaria, and as the Liaison Office to the American Embassy in Austria.

Upon leaving the Army in 1973, he joined the firm of Jones, McIntosh, Threlkeld, Newman & Cox in South Carolina where he served as a trial lawyer in state and federal courts. In April 1978, he was elected a Resident Judge of the 10th Judicial Circuit of South Carolina. He also served as an Acting Associate Justice of the South Carolina Supreme Court; a Hearing Officer of the Judicial Standards Commission; and on the Judicial Council, the Circuit Court Advisory Committee. Judge Cox also served as a member of The House of Delegates of the South Carolina Bar and the Board of Commissioners on Grievances and Discipline. He also played a major role in the formation of the American Federal Inn of Court.