John Abt

John Jacob Abt (May 1, 1904, Chicago – August 10, 1991, Hudson, New York) was an American lawyer and politician. He spent most of his career as chief counsel to the Communist Party USA (CPUSA).

Abt was a graduate of the University of Chicago, and from its law school. He practiced real estate and corporate law in Chicago from 1927 to 1933.

He was the Chief of Litigation, Agricultural Adjustment Administration from 1933 to 1935, assistant general counsel of the Works Progress Administration in 1935, chief counsel to Senator Robert La Follette, Jr.'s Committee from 1936 to 1937 and special assistant to the United States Attorney General, 1937 and 1938.

From 1938 to 1948, he worked at chief counsel of the Amalgamated Clothing Workers Union under Sidney Hillman, who hired him. By January 1946, he was also working as general counsel for the Congress of Industrial Organizations (CIO) and traveled to Russia with a CIO delegation, which included Lee Pressman. (The CIO had long-term support from communists; in 1947, CIO leaders like Walter Reuther pushed out communist elements and again in 1949 after the CIO's merger with the American Federation of Labor (AFL) to form the AFL-CIO.)