McIntosh served in the United States Air Force from 1942 to 1945 and was assigned to the Eighth Air Force in England as a fighter pilot. He served as assistant prosecuting attorney of Saint Clair County from 1949 to 1951 and as postmaster at Port Huron from October 1, 1953, to February 4, 1955. McIntosh was a member of the U.S. House of Representatives' Committee on Un-American Activities (HUAC).
In 1963, McIntosh served as chairman of the Michigan State Public Service Commission. He also served as executive assistant to Michigan GovernorGeorge W. Romney from 1964 to 1965 and as director of the Michigan Department of Commerce in 1966. He resumed the practice of law and was a resident of Port Huron, Michigan, and Vero Beach, Florida.
McIntosh died in Fort Gratiot, Michigan, on March 22, 2008.[2] He was buried at Lakeside Cemetery in Port Huron.[3]