Related Rule
New Zealand
Practice Relating to Rule 154. Obedience to Superior Orders
New Zealand’s Military Manual (1992) provides: “One such obligation, and the one which clearly sets a member of a military force apart from his civilian counterparts, is the obligation to obey lawful commands of a superior officer.” 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, Annex C, § C14(1).
The manual adds, however: “If a command is unlawful and is obeyed, the person who obeys it could find himself charged with a criminal offence or a war crime”. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, Annex C, § C14(2).
The manual also states:
If it is obvious that an order is unlawful, then it should not be obeyed. Orders which are obviously unlawful are extremely rare. An order to torture or kill prisoners of war or innocent civilians or to loot civilian property would be obviously unlawful. This kind of order should never be obeyed and it should never be assumed that it will provide a defence if a charge results from its obedience. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, Annex C, § C14(4).
The manual further points out:
If … an unclear order is received, and especially if one of the possible meanings of the order appears to be unlawful, then clarification should be sought immediately. Blind obedience, in such cases, is not what is required. In … cases of unclear orders, blind obedience could lead to unfortunate and perhaps unforeseen results. In our example, both the sergeant and the superior whom we infer meant to convey nothing in any way illegal, could find themselves the subject of serious charges, simply because an unclear order was not clarified or questioned. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, Annex C, § C14(5).