Related Rule
New Zealand
Practice Relating to Rule 68. Precautions while Receiving Parlementaires
New Zealand’s Military Manual (1992) states:
The belligerent to whom a parlementaire is proceeding may take all steps necessary to protect the safety of his position or unit and to prevent the parlementaire from taking advantage of his visit to secure information. The adverse Party may prescribe the route to be taken by the parlementaire or may bind his eyes, may limit the size of the party or take similar action. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 406(5).
New Zealand’s Military Manual (1992) states:
If the parlementaire stays within enemy lines after being ordered to withdraw he loses his inviolability and may be made a prisoner of war. He may similarly be detained and tried if there is prima facie evidence that he has abused his position as a parlementaire, for example by collecting information surreptitiously. It is not an abuse of his position for the parlementaire to report back anything he may have observed. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 406(7).