This paper examines how establishing a new legal institution shapes understandings and practices of citizenship. It does so through a study of the creation of the Court of Bosnia and Herzegovina (CBiH) between 2002 and 2014 and, in particular, its emerging jurisdiction over war crimes trials since 2006. International sponsors of this institution herald the establishment of the Court as an important step toward achieving justice for the crimes committed during the 1992–1995 conflict in Bosnia and Herzegovina (BiH). But alongside its legal function, intervening agencies have emphasised an allied objective to use the Court to consolidate state structures and foster a civic sense of Bosnian citizenship. Using qualitative data, this paper argues that the creation of the CBiH illuminates a series of divergent understandings of citizenship. In particular, while the court seeks to convey a concept of liberal democratic citizenship, this is only achieved through the enrolment of civil society actors operating across BiH territory. Rather than heralding a series of ‘grassroots’ alternatives to official scripts, these social agents see the value of a universal understanding of justice structured around equality and rights, but often failed to see this expressed in the activities of the Court. The paper concludes by reflecting on the relationship between law and citizenship, where the imagined sense of universal jurisdiction is undermined by social concerns relating to the barriers that prevent access to justice.