In the 1960s and early 1970s deviance research, especially in the labeling perspective, was concerned with the question of how individuals or groups become defined as deviant. Since then, the political analysis of deviance has come to ask the more fundamental question of how deviance becomes constructed through political processes. A political trial is one particularly transparent situation in which narrower political processes for imputing deviance elicit more fundamental interpretations of political modes of deviance construction. In order to explore the workings of the deviance construction process, the present study examines the two defense strategies employed on behalf of the defendants in the trial of the Chicago 15, a group of thirteen men and two women who destroyed selective service files on the south side of Chicago in May, 1969. The first strategy is the previously studied “motivation defense,” wherein the moral righteousness of the defendants' purpose is pleaded as cause for their exculpation. The second is the unique “cultural insanity defense,” which asserts that the defendants were so profoundly deluded in their moral indictment of the government that the jury should return a verdict of culturally insane rather than criminally guilty. The first section of the paper summarizes the circumstances of the trial. The second and third sections analyze each of the two defense strategies, focusing on their legal and political logic and on the prosecution counter-strategies they engendered. The final section indicates a number of theoretical implications for the further development of the political model of political trials and of deviance construction in society at large.