Can military necessity override POW rights?
NO. The Geneva Conventions Act 1957 provides prisoners of war with certain fundamental guarantees for humane treatment at Article 4 of Part 2 of Schedule 6:
1 All persons who do not take a direct part or who have ceased to take part in hostilities, whether or not their liberty has been restricted, are entitled to respect for their person, honour and convictions and religious practices. They shall in all circumstances be treated humanely, without any adverse distinction. It is prohibited to order that there shall be no survivors.
2 Without prejudice to the generality of the foregoing, the following acts against the persons referred to in paragraph 1 are and shall remain prohibited at any time and in any place whatsoever:
(a) violence to the life, health and physical or mental well-being of persons, in particular murder as well as cruel treatment such as torture, mutilation or any form of corporal punishment;
(b) collective punishments;
(c) taking of hostages;
(d) acts of terrorism;
(e) outrages upon personal dignity, in particular humiliating and degrading treatment, rape, enforced prostitution and any form of indecent assault;
(f) slavery and the slave trade in all their forms;
(h) threats to commit any of the foregoing acts
4 If it is decided to release persons deprived of their liberty, necessary measures to ensure their safety shall be taken by those so deciding.
Q1 What shall he do?
- The humane and fair treatment of prisoners of war takes primacy, so if the commander cannot complete his mission without properly securing the prisoners it should be aborted until he can.
Q2 Is it legal to release him? Shoot him?
- There is nothing to prevent a prisoner being released (para 4) but shooting him will probably amount to murder and may well be a war crime.
Q3 What should they do?
- As combatants, they should guarantee the prisoner be treated humanely and without distinction - a lack of amenities does not necessarily equate to inhumane treatment, although it may depend on the particular circumstances.
Q4 Are they allowed to kill him?
- No, the prisoner's liberty has been restricted so the fireteam must treat him humanely, which may mean aborting the mission if they cannot safely release him - killing him will probably amount to murder and may well be a war crime.
I assume the united-states has similar, if not identical provisions