This study analyzes how the Dutch criminal justice system works from an abstract and a practical perspective. Using data collected through quantitative (police and prosecution databases) and qualitative (interviewing of key participants familiar with the databases and observation of some ongoing trials) procedures, it identifies the main features of this system as well as the main problems that researchers might have when working with data recorded by the police and the prosecution service. This is a methodological paper that intends to contribute with the data analysis research in this field. (Published Abstract)