The data available to law enforcement agencies is divided into two categories : •
Nominal data directly designates persons or objects (recidivists, intelligence files and suspect files, stolen vehicles or objects, etc.) and their relations. Nominal data may also be obtained in the framework of specific investigations. This could include for instance, a list of calls made with a
mobile phone (card and/or phone) that cover a certain time period, a list of people corresponding to a certain profile, or data obtained through surveillances. •
Crime data consists of traces that result from criminal activities: physical traces, other information collected at the scene, from witnesses or victims or some electronic traces, as well as reconstructed descriptions of cases (modus operandi, time intervals, duration and place) and their relations (links between cases, series). == Types ==