During the tumultuous 1980s, Polish People’s Republic experimented with legal reforms and institutions of the constitutional state. Among these institutions, set up according to the ideas of socialist legality, was the State Tribunal, tasked with determining accountability of the former leadership from the 1970s. Brought to life amid debates around economic crisis and official corruption and legally and politically constrained, the Tribunal failed to satisfy popular demands for justice. This article explores the idea of socialist legality by looking at the history of the State Tribunal in Poland. It analyses different understandings of justice and accountability, expressed during the Solidarity Revolution, and shows how they played out in public debates and the legislative process. In order to guarantee legitimacy in the unstable political situation, Polish socialist legality needed to go further than in other Eastern Bloc countries and to address popular grievances. In Poland therefore, socialist constitutional state-building started before martial law and significantly predated the turn to liberal democracy and market capitalism in 1989.