All case files pertaining to a given period are generally complete within three months.
For our purposes, the case files for March 1999 were analysed between the beginning of May and the end of June of the same year. We may in fact define a user by the offence of which he is suspected and for which he is counted in the statistics, or by the person's behaviour as revealed by the contents of the hearing. The establishment of a formally correct case file by the criminal investigation police is based on an administrative break- down of police work corresponding to extremely precise constraints and practices. When the police hands over a suspect, with the consent of the prosecutor's office, it transmits the case file at the same time. This means that it must construct a legally coherent whole even if the elements do not necessarily account completely for what happened.