Defendants included: Communist Party (CPUSA), state-level Party organizations, individual Communist and Progressive activists, radical and/or Communist-associated labor unions and their leaders and activists, Puerto Rican nationalists, and fellow lawyers charged with contempt and other crimes in connection with their defense of radicals.
[3] In 1949, he defended some of the twelve Party leaders in the Smith Act trials (charged with conspiring to advocate violent overthrow of the U.S.
[1] In 1951, Unger joined more than half a dozen other lawyers in defending 17 Communist Party members, including Elizabeth Gurley Flynn.
The other lawyers were: Abraham L. Pomerantz, Carol Weiss King, Victor Rabinowitz, Michael Begun, Harold I. Cammer, Mary Kaufman, and Leonard Boudin.
[1] In the mid-1950s, he defended Puerto Rican nationalist Juan Bernardo Lebron, charged as a conspirator in the 1954 attack on the U.S. House of Representatives.