He served as vice president (1928–1966) of the Amalgamated Clothing Workers of America (ACW) under Sidney Hillman, affiliated throughout with either the AFL or CIO or merged AFL–CIO.
He also was head of the CIO-PAC (1946–1955), and was close to U.S. Presidents Franklin Delano Roosevelt and Harry S.
[1] In addition to his national role, Kroll was an early member of the board of directors of a Democrat-Republican "City Charter Committee" in Cincinnati as well as president of the Ohio CIO council (1932–1952).
[1] In 1920, Jack Kroll married Sara Sylvia Ruben, whom he had met the year before on a picket line.
[1] Kroll died age 85 in Cincinnati, Ohio, survived by his wife, son, and five grandchildren.