Article 304
If it is necessary in order to protect the interests of national security, public order and morality, interests of minors, privacy of participants in proceedings, or for other justified interests in a democratic society, the authority conducting proceedings which conducts an evidentiary action shall order persons he is questioning or examining or who are attending evidentiary actions or are examining the case-file to maintain confidentiality of certain facts or data learnt on the occasion, and warn them that disclosure of a secret represents a criminal offence under the law.
The order referred to in paragraph 1 of this Article will be entered into transcript of the evidentiary action, or will be marked on the case-file documents which are being examined and accompanied by a signature of the person warned.
1. States Parties shall, in accordance with the provisions of this Part and under procedures of national law, comply with requests by the Court to provide the following assistance in relation to investigations or prosecutions:
(j) The protection of victims and witnesses and the preservation of evidence;