The Law of Land Warfare, 1956

2.    Purposes of the Law of War

The conduct of armed hostilities on land is regulated by the law of land warfare which is both written and unwritten.  It is inspired by the desire to diminish the evils of war by:

    a.    Protecting both combatants and non-combatants from unnecessary suffering;

    b.    Safeguarding certain fundamental human rights of persons who fall into the hands of the enemy, particularly prisoners of war, the wounded and sick, and civilians; and

    c.    Facilitating the restoration of peace....

3.    Basic Principles

    a.    Prohibitory Effect.  The law of war places limits on the exercise of a belligerent's power in the interests mentioned in paragraph 2 and requires that belligerents refrain from employing any kind or degree of violence which is not actually necessary for military purposes and that they conduct hostilities with regard for the principles of humanity and chivalry.

    The prohibitory effect of the law of war is not minimized by "military necessity" which has been defined as that principle which justifies those measures not forbidden by international law which are indispensable for securing the complete submission of the enemy as soon as possible.  Military necessity has been generally rejected as a defense for acts forbidden by the customary and conventional laws of war inasmuch as the latter have been developed and framed with consideration for the concept of military necessity.

    b.     Binding on States and Individuals.  The law of war is binding not only upon States as such but also upon individuals and, in particular, the members of their armed forces....

498.  Crimes Under International Law

Any person, whether a member of the armed forces or a civilian. who commits an act which constitutes a crime under international law is responsible thereof and liable to punishment....

499.  War Crimes

The term "war crime" is a technical expression for violation of the law of war by any person or persons, military or civilian.  Every violation of the law of war is a war crime....

501.  Responsibility for Acts of Subordinates

In some cases, military commanders may be responsible for war crimes committed by subordinate members of the armed forces, or other persons subject to their control.  Thus, for instance, when troops commit massacres and atrocities against the civilian population of occupied territory or against prisoners of war, the responsibility may rest not only with the actual perpetrators but also with the commander.  Such a responsibility arises directly when the acts in question have been committed in pursuance of an order of the commander concerned.  The commander is also responsible if he has actual knowledge, or should have knowledge, through reports received by him or through other means, that troops or other persons subject to his control are about to commit or have committed a war crime and he fails to take the necessary and reasonable steps to insure compliance with the law of war or to punish violators thereof....

505.  Universality of Jurisdiction

. . . b.    Persons Charged with War Crimes.  The United States normally punishes war crimes as such only if they are committed by enemy nationals or by persons serving the interests of the enemy State.  Violations of the law of war committed by persons subject to military law of the United States will usually constitute violations of the Uniform Code of Mlitary Justice and, if so, will be prosecuted under that Code.... Commanding officers of United States troops must insure that war crimes committed by members of their forces against enemy personnel are promptly and adequately punished.

508.  Penal Sanctions

The punishment imposed for a violation of the law of war must be proportionate to the gravity of the offense.  The death penalty may be imposed for grave breaches of the law....

509.  Defense of Superior Orders

    a.     The fact that the law of war has been violated pursuant to an order of a superior authority, whether military or civil, does not deprive the act in question of its character as a war crime, nor does it constitute a defense in the trial of an accused individual, unless he did not know and could not reasonably have been expected to know that the act was unlawful.  In all cases where the order is held not to constitute a defense to an allegation of war crime, the fact that the individual was acting pursuant to orders may be considered in mitigation of punishment.

    b.     In considering the question of whether a superior order constitutes a valid defense, the court shall take into consideration the fact that obedience to lawful military orders is the duty of every member of the armed forces; that the latter cannot be expected, in conditions of war discipline, to weigh scrupulously the legal merits of the order received; that certain rules of warfare may be controversial; or that an act otherwise amounting to a war crime may be done in obedience to orders conceived as a measure of reprisal.  At the same time it must be borne in mind that members of the armed forces are bound to obey only lawful orders.

510.  Government Officials

The fact that a person who committed an act which constitutes a war crime acted as the head of a State or as a responsible government official does not relieve him from responsibility for his act.