He graduated from
Harvard Law School in 1937 and was immediately appointed to the faculty of the
University of Iowa College of Law by the dean of the law school (and future U.S. Supreme Court justice)
Wiley B. Rutledge. Wirtz was a professor of law at
Northwestern University from 1939 to 1942. He served with the
War Labor Board from 1943 to 1945, and was chairman of the
National Wage Stabilization Board in 1946. Wirtz returned to teach law at Northwestern until 1954. His students included future
U.S. Supreme Court justice
John Paul Stevens, whom Wirtz recommended for what became his 1947–48 clerkship with Justice Rutledge. He was active in Democratic politics and wrote speeches for
Adlai Stevenson during his 1952 Presidential campaign. More than 18,000 were recruited for the A-TEAM, or
Athletes in Temporary Employment as Agricultural Manpower, but only 3,300 ever worked in the fields, and many of them quickly quit or staged
strikes because of the poor working conditions, including oppressive heat and decrepit housing. Wirtz's relationship with Johnson was compromised by Wirtz sending a private memorandum to the President expressing concerns about the United States' involvement in the
Vietnam War. ==Later life==