People are equal before the law. This principle is strongly embedded in the judicial doctrine of the Enlightenment, and for that matter also in the liberal Belgian constitution. In practice, however, justice administration does not always follow that rule: some people appear to be more equal before the law than others. Investigating the social profiles and penal trajectories of persons confronted with criminal justice in 19th-century Belgium, this historical-criminological research project aims to determine how different dimensions of social vulnerability (gender, class, age, migration background...) shape the workings of criminal justice. Using this intersectional approach, we examine how various social vulnerabilities affect uses, practices and experiences of justice. By reconstructing the untold stories of vulnerable ‘outsiders’ in their dealings with the law, this project also aims to give voice to largely underrepresented groups in history. To achieve this, it draws on the extraordinary rich collections of judicial and prison records kept by the Belgian State Archives, that provide unique access to the voices and experiences of ‘ordinary’ men and women in the past.