Part Three. Court Proceedings
Section IX. Proceedings in a Court of the First Instance
Chapter 35. General Conditions for the Judicial Proceedings
Article 241. Openness
2. Conducting the judicial proceedings in camera shall be admissible on the ground of a court ruling or resolution, if:
4) this is called forth by the interests of guaranteeing security for the participants in the judicial proceedings, for their close relatives, relations or near persons.
National judicial procedures protecting witnesses from identification – witness protection
EDIT.