Law of war


The law of war refers to the component of international law that regulates the conditions for war and the conduct of warring parties. Laws of war define sovereignty and nationhood, states and territories, occupation, and other critical terms of international law.
Among other issues, modern laws of war address the declarations of war, acceptance of surrender and the treatment of prisoners of war; military necessity, along with distinction and proportionality; and the prohibition of certain weapons that may cause unnecessary suffering.
The law of war is considered distinct from other bodies of law—such as the domestic law of a particular belligerent to a conflict—which may provide additional legal limits to the conduct or justification of war.

Early sources and history

Attempts to define and regulate the conduct of individuals, nations, and other agents in war and to mitigate the worst effects of war have a long history. The earliest known instances are found in the Mahabharata and the Old Testament.
In the Indian subcontinent, the Mahabharata describes a discussion between ruling brothers concerning what constitutes acceptable behavior on a battlefield, an early example of the rule of proportionality:
An example from the Book of Deuteronomy 20:19–20 limits the amount of environmental damage:
Also, Deuteronomy 20:10–12 requires the Israelites to make an offer of conditioned peace to the opposing party before laying siege to their city.
Similarly, Deuteronomy 21:10–14 requires that female captives who were forced to marry the victors of a war could not be sold as slaves.
In the early 7th century, the first caliph, Abu Bakr, whilst instructing his Muslim army, laid down the following rules concerning warfare:
Furthermore, Sura Al-Baqara of the Quran requires that in combat Muslims are only allowed to strike back in self-defense against those who strike against them, but, on the other hand, once the enemies cease to attack, Muslims are then commanded to stop attacking.
In the history of the early Christian church, many Christian writers considered that Christians could not be soldiers or fight wars. Augustine of Hippo contradicted this and wrote about 'just war' doctrine, in which he explained the circumstances when war could or could not be morally justified.
In 697, Adomnan of Iona gathered Kings and church leaders from around Ireland and Scotland to Birr, where he gave them the 'Law of the Innocents', which banned killing women and children in war, and the destruction of churches.
In medieval Europe, the Roman Catholic Church also began promulgating teachings on just war, reflected to some extent in movements such as the Peace and Truce of God. The impulse to restrict the extent of warfare, and especially protect the lives and property of non-combatants continued with Hugo Grotius and his attempts to write laws of war.
One of the grievances enumerated in the American Declaration of Independence was that King George III "has endeavoured to bring on the inhabitants of our frontiers the merciless Indian Savages whose known rule of warfare is an undistinguished destruction of all ages, sexes and conditions".

Modern sources

The modern law of war is made up from three principal sources:
Positive international humanitarian law consists of treaties that directly affect the laws of war by binding consenting nations and achieving widespread consent.
The opposite of positive laws of war is customary laws of war, many of which were explored at the Nuremberg War Trials. These laws define both the permissive rights of states as well as prohibitions on their conduct when dealing with irregular forces and non-signatories.
The Treaty of Armistice and Regularization of War signed on November 25 and 26, 1820 between the president of the Republic of Colombia, Simón Bolívar and the Chief of the Military Forces of the Spanish Kingdom, Pablo Morillo, is the precursor of the International Humanitarian Law. The Treaty of Guadalupe Hidalgo, signed and ratified by the United States and Mexico in 1848, articulates rules for any future wars, including protection of civilians and treatment of prisoners of war. The Lieber Code, promulgated by the Union during the American Civil War, was critical in the development of the laws of land warfare. Historian Geoffrey Best called the period from 1856 to 1909 the law of war's "epoch of highest repute." The defining aspect of this period was the establishment, by states, of a positive legal or legislative foundation superseding a regime based primarily on religion, chivalry, and customs. It is during this "modern" era that the international conference became the forum for debate and agreement between states and the "multilateral treaty" served as the positive mechanism for codification.
In addition, the Nuremberg War Trial judgment on "The Law Relating to War Crimes and Crimes Against Humanity" held, under the guidelines Nuremberg Principles, that treaties like the Hague Convention of 1907, having been widely accepted by "all civilised nations" for about half a century, were by then part of the customary laws of war and binding on all parties whether the party was a signatory to the specific treaty or not.
Interpretations of international humanitarian law change over time and this also affects the laws of war. For example, Carla Del Ponte, the chief prosecutor for the International Criminal Tribunal for the former Yugoslavia pointed out in 2001 that although there is no specific treaty ban on the use of depleted uranium projectiles, there is a developing scientific debate and concern expressed regarding the effect of the use of such projectiles and it is possible that, in future, there may be a consensus view in international legal circles that use of such projectiles violates general principles of the law applicable to use of weapons in armed conflict. This is because in the future it may be the consensus view that depleted uranium projectiles breach one or more of the following treaties: The Universal Declaration of Human Rights; the Charter of the United Nations; the Genocide Convention; the United Nations Convention Against Torture; the Geneva Conventions including Protocol I; the Convention on Conventional Weapons of 1980; the Chemical Weapons Convention; and the Convention on the Physical Protection of Nuclear Material.

Purposes of the laws

It has often been commented that creating laws for something as inherently lawless as war seems like a lesson in absurdity. But based on the adherence to what amounted to customary international law by warring parties through the ages, it was believed that codifying laws of war would be beneficial.
Some of the central principles underlying laws of war are:
To this end, laws of war are intended to mitigate the hardships of war by:
Military necessity, along with distinction, proportionality, humanity, and honor are the five most commonly cited principles of international humanitarian law governing the legal use of force in an armed conflict.
Military necessity is governed by several constraints: an attack or action must be intended to help in the defeat of the enemy; it must be an attack on a legitimate military objective, and the harm caused to civilians or civilian property must be proportional and not excessive in relation to the concrete and direct military advantage anticipated.
Distinction is a principle under international humanitarian law governing the legal use of force in an armed conflict, whereby belligerents must distinguish between combatants and civilians.
Proportionality is a principle under international humanitarian law governing the legal use of force in an armed conflict, whereby belligerents must make sure that the harm caused to civilians or civilian property is not excessive in relation to the concrete and direct military advantage expected by an attack on a legitimate military objective.
Humanity. This principle is based in the Hague Conventions restrictions against using arms, projectiles, or materials calculated to cause suffering or injury manifestly disproportionate to the military advantage realized by the use of the weapon for legitimate military purposes. In some countries, like the United States, weapons are reviewed prior to their use in combat to determine if they comply with the law of war and are not designed to cause unnecessary suffering when used in their intended manner. This principle also prohibits using an otherwise lawful weapon in a manner that causes unnecessary suffering.
Honor is a principle that demands a certain amount of fairness and mutual respect between adversaries. Parties to a conflict must accept that their right to adopt means of injuring each other is not unlimited, they must refrain from taking advantage of the adversary’s adherence to the law by falsely claiming the law’s protections, and they must recognize that they are members of a common profession that fights not out of personal hostility but on behalf of their respective States.

Example substantive laws of war

To fulfill the purposes noted above, the laws of war place substantive limits on the lawful exercise of a belligerent's power. Generally speaking, the laws require that belligerents refrain from employing violence that is not reasonably necessary for military purposes and that belligerents conduct hostilities with regard for the principles of humanity and chivalry.
However, because the laws of war are based on consensus, the content and interpretation of such laws are extensive, contested, and ever-changing. The following are particular examples of some of the substance of the laws of war, as those laws are interpreted today.

Declaration of war

Section III of the Hague Convention of 1907 required hostilities to be preceded by a reasoned declaration of war or by an ultimatum with a conditional declaration of war.
Some treaties, notably the United Nations Charter Article 2, and other articles in the Charter, seek to curtail the right of member states to declare war; as does the older Kellogg–Briand Pact of 1928 for those nations who ratified it. Formal declarations of war have been uncommon since 1945 outside the Middle East and East Africa.

Lawful conduct of belligerent actors

Modern laws of war regarding conduct during war, such as the 1949 Geneva Conventions, provide that it is unlawful for belligerents to engage in combat without meeting certain requirements, such as wearing distinctive uniform or other distinctive signs visible at a distance, carrying weapons openly, and conducting operations in accordance with the laws and customs of war. Impersonating enemy combatants by wearing the enemy's uniform is allowed, though fighting in that uniform is unlawful perfidy, as is the taking of hostages.
Combatants also must be commanded by a responsible officer. That is, a commander can be held liable in a court of law for the improper actions of his or her subordinates. There is an exception to this if the war came on so suddenly that there was no time to organize a resistance, e.g. as a result of a foreign occupation.

People parachuting from an aircraft in distress

Modern laws of war, specifically within Protocol I additional to the 1949 Geneva Conventions, prohibits attacking people parachuting from an aircraft in distress regardless of what territory they are over. Once they land in territory controlled by the enemy, they must be given an opportunity to surrender before being attacked unless it is apparent that they are engaging in a hostile act or attempting to escape. This prohibition does not apply to the dropping of airborne troops, special forces, commandos, spies, saboteurs, liaison officers, and intelligence agents. Thus, such personnel descending by parachutes are legitimate targets and, therefore, may be attacked, even if their aircraft is in distress.

Red Cross, Red Crescent, Magen David Adom, and the white flag

Modern laws of war, such as the 1949 Geneva Conventions, also include prohibitions on attacking doctors, ambulances or hospital ships displaying a Red Cross, a Red Crescent, Magen David Adom, The Red Crystal, or other emblem related to the International Red Cross and Red Crescent Movement. It is also prohibited to fire at a person or vehicle bearing a white flag, since that indicates an intent to surrender or a desire to communicate.
In either case, people protected by the Red Cross/Crescent/Star or white flag are expected to maintain neutrality, and may not engage in warlike acts. In fact, engaging in war activities under a protected symbol is itself a violation of the laws of war known as perfidy. Failure to follow these requirements can result in the loss of protected status and make the individual violating the requirements a lawful target.

Applicability to 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. Parties are bound by the laws of war to the extent that such compliance does not interfere with achieving legitimate military goals. For example, they are obliged to make every effort to avoid damaging people and property not involved in combat or the war effort, but they are not guilty of a war crime if a bomb mistakenly or incidentally hits a residential area.
By the same token, combatants that intentionally use protected people or property as human shields or camouflage are guilty of violations of the laws of war and are responsible for damage to those that should be protected. The use of contracted combatants in warfare has been an especially tricky situation for the laws of war. Some scholars claim that private security contractors appear so similar to state forces that it is unclear if acts of war are taking place by private or public agents. International law has yet to come to a consensus on this issue.

Remedies for violations

During conflict, punishment for violating the laws of war may consist of a specific, deliberate and limited violation of the laws of war in reprisal.
After a conflict ends, persons who have committed or ordered any breach of the laws of war, especially atrocities, may be held individually accountable for war crimes through process of law. Also, nations that signed the Geneva Conventions are required to search for, then try and punish, anyone who has committed or ordered certain "grave breaches" of the laws of war.
Combatants who break specific provisions of the laws of war are termed unlawful combatants. Unlawful combatants who have been captured may lose the status and protections that would otherwise be afforded to them as prisoners of war, but only after a "competent tribunal" has determined that they are not eligible for POW status At that point, an unlawful combatant may be interrogated, tried, imprisoned, and even executed for their violation of the laws of war pursuant to the domestic law of their captor, but they are still entitled to certain additional protections, including that they be "treated with humanity and, in case of trial, shall not be deprived of the rights of fair and regular trial."

International treaties on the laws of war

List of declarations, conventions, treaties, and judgments on the laws of war:

General sources