If the police or a citizen suspects you of a criminal offence, they may arrest you. If you are arrested by a civilian, the civilian must hand you over to the police as soon as possible. 

The police has the right, if they did arrest you, to place you in a holding cell for the coming nine hours. The clock starts counting after the assistant district attorney visits you. Most of the time the assistant district attorney will also inform you about your rights and the standard procedure. This is called in Dutch voorgeleiding. The hours between 12:00 a.m. and 09:00 a.m. do not count.  These first nine hours should be used in principle for the first interrogation.  Before the first interrogation, the police officer will always ask if you want to consult an attorney and if you want an attorney present during the interrogation.