When processing personal data, the controller shall, as far as possible, make a clear distinction between different categories of data subjects. This applies in particular to the following categories:
1. persons with regard to whom there are serious grounds for believing that they have committed a criminal offence;
2. persons with regard to whom there are serious grounds for believing that they are about to commit a criminal offence;
3. persons convicted of a criminal offence;
4. victims of a criminal offence or persons with regard to whom certain facts indicate that they could be the victim of a criminal offence; and
5. other persons, such as witnesses, persons who can provide information, or contacts or associates of the persons referred to in nos. 1 to 4.