From 1939 to 1947, Marshall was a member of the Board of Directors of the American Civil Liberties Union. During that period, he aligned with the faction which favored a more absolutist defense of civil liberties. Most notably, unlike the majority of the Board, he was consistent in his opposition to Roosevelt's Executive Order 9066, which put Japanese Americans into concentration camps. Also, in contrast to most of the Board, Marshall charged that the prosecution of thirty-two right wing opponents of Roosevelt's pre-war foreign policy in the Sedition Trial of 1944 violated the First Amendment.
From 1939 to 1947 Marshall was a member of the Board of Directors of the American Civil Liberties Union During that period he aligned with the faction which favored a more absolutist defense of civil liberties Most notably unlike the majority of the Board he was consistent in his opposition to Roosevelt's Executive Order 9066 which put Japanese Americans into concentration camps Also in contrast to most of the Board Marshall charged that the prosecution of thirty-two right wing opponents of Roosevelt's pre-war foreign policy in the Sedition Trial of 1944 violated the First Amendment