 After clerking for United States District Court for the Central District of California Judge Robert J. Kelleher (1971–72), he practiced in San Francisco at Pillsbury, Madison & Sutro.Walker was originally nominated to the bench by President Ronald Reagan in 1987.However, this nomination stalled in the Senate Judiciary Committee because of controversy over his representation of the United States Olympic Committee in a lawsuit that prohibited the use of the title "Gay Olympics".