Opening a Black Box: Introducing a New Dataset on the Composition of German Administrative Courts

German administrative courts play a central role in asylum adjudication, yet systematic research has been hampered by the lack of court-level data on judicial staffing. This research note introduces the German Administrative Court Composition (GACC) dataset, the first machine-readable documentation of all German administrative courts, based on digitised entries from the Handbook of the Judiciary. The dataset records the number of judges, their age, gender, academic titles, and position, and can be linked to the Administrative Court Statistics. This enables analyses of organisational and demographic variation across courts and their relation to judicial performance, which has been under stress in Germany for over a decade now. The paper introduces the dataset, assesses its coverage, and presents first insights into the composition of German administrative courts and how it can be used in future research. The data provide a new foundation for empirical research on court composition, performance, and asylum adjudication.