Humanitarian law

Definitions & Introductions

Humanitarian law is a set of principles and international treaties outlining the conduct of nations engaged in warfare that aim to protect combatants and civilians affected by armed conflicts. It is also known as the law of war or the law of armed conflict.

Humanitarian law seeks to limit the effects of armed conflict on combatants and civilians by defining their fundamental rights. The principles of humanitarian law are found in the Geneva Conventions of 1949 and the Hague Conventions, in addition to several other agreements signed by most nations. These rights are expanded in the 1977 Protocol Additional to the Geneva Conventions. International humanitarian law complements international law, which is a set of rules that govern relations between states.

Featured Reading

Red Cross: What is international humanitarian law?

Download the fact sheet providing a summary description of the sources, content, and field of application of international humanitarian law.

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Accountability: How to Treat Unlawful Combatants

Carnegie Council President Joel Rosenthal advocated for the establishment of an accountability mechanism to review policy misjudgments resulting in war-time abuses.

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Civilians and War: Dilemmas in Law and Morality

Published in 2002, Anthony F. Lang, Jr details how the status of civilians during military conflicts may have changed based on the events in Afghanistan and the Middle East at the time.

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Who is a Prisoner of War?

Read the 2002 BBC News resource detailing the Geneva Convention's definition of a prisoner of war and the precedents that the definition pulls from.

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Additional Terminology

Principle of distinction

The principle of distinction is established by Article 48 of Protocol I of the 1977 Protocol Additional to the Geneva Conventions, which states that "Parties to the conflict shall at all times distinguish between the civilian population and combatants and between civilian objects and military objectives and accordingly shall direct their operations only against military objectives." In armed conflict, this principle prohibits the use of indiscriminate weapons and the use of legal weapons in indiscriminate ways.

Indiscriminate weapons


Indiscriminate weapons are difficult to aim or have difficult-to-control effects. Few weapons are inherently indiscriminate; this could easily change, however, as new war-fighting technologies are developed.

Indiscriminate use of legal weapons


Indiscriminate use of legal weapons refers to the use of legal weapons that are not properly targeted or target civilian and military objects and/or populations without distinction. There are three criteria for determining this: discrimination, proportionality, and duty of care. Articles 51 through 58 of Protocol I further define these criteria and the issue of indiscriminate use of weapons against civilian targets.

Prisoners of War


Combatants "who have fallen into the power of the enemy" are considered prisoners of war (POWs). International law provides for the general rights, protection, and treatment of POWs while they are in captivity or internment. According to The Geneva Convention Relative to the Treatment of Prisoners of War (1949), POWs also include members of the armed forces, volunteer corps, militias, those accompanying the armed forces, and civilians or inhabitants of an area who take up arms to resist invading forces. Protocol I (1977) provides additional information related to the definition and treatment of POWs.