6. International Humanitarian Law (IHL)

Official Syllabus Focus

• International/non-international armed conflict
• Combatants/protected persons
• Wounded, sick, shipwrecked
• POWs
• Civilians
• Limits on methods and means

Introduction and Scope

When IHL applies

International humanitarian law applies because an armed conflict exists, not because the conflict has been legally justified under the law on the use of force. This distinction is essential. Jus ad bellum addresses whether resort to force is lawful; jus in bello or IHL regulates conduct once the legal threshold of armed conflict is reached.

The first analytical step is classification. International armed conflicts generally involve resort to armed force between states. Non-international armed conflicts involve sufficiently intense protracted armed violence between state authorities and organized armed groups, or between such groups, subject to the applicable legal tests. Classification determines which treaty rules apply, though customary IHL also matters.

Protection of persons

The Geneva Conventions establish protection for wounded and sick members of armed forces, wounded, sick and shipwrecked persons at sea, prisoners of war, and civilians in international armed conflict. Common Article 3 provides minimum protections in non-international armed conflict. Additional treaty and customary rules regulate detention, humane treatment and specific vulnerable categories.

A person may be protected because of status or because the person is hors de combat—out of the fight due to surrender, detention, unconsciousness or another legally recognized condition. Protection is not a reward for political sympathy; it is a legal consequence of humanitarian rules.

Conduct of hostilities

Distinction requires parties to direct operations against military objectives and not civilians or civilian objects as such. Proportionality prohibits attacks expected to cause incidental civilian harm excessive in relation to the concrete and direct military advantage anticipated. Precautions require feasible steps to verify targets and reduce civilian harm.

These principles are connected but different. A civilian object does not become targetable merely because anticipated collateral damage appears small; targetability first depends on whether it qualifies as a military objective. Proportionality is assessed only after a lawful military objective has been identified.

Key Comparison

Core Concepts Explained

• IHL begins once the legal threshold of armed conflict is met. Its application does not depend on whether one side had a lawful reason to start the conflict.
• First classify the conflict as international or non-international because classification affects the applicable treaty framework and legal rules.
• The principle of distinction requires parties to distinguish military objectives and combatants from civilians and civilian objects. Proportionality restricts attacks expected to cause excessive incidental civilian harm in relation to the concrete and direct military advantage anticipated.
• Precautions require feasible steps to reduce civilian harm. Separate rules protect wounded, sick, shipwrecked persons, prisoners and detainees, and persons who are no longer participating in hostilities.
• IHL also limits weapons and methods of warfare through treaty and customary rules. Humanitarian protection and military necessity operate within a legal framework, not as unlimited competing slogans.

Preparation and Answer Use

• Keep IHL separate from the legality of starting a war.
• Prepare protected categories and basic targeting principles.
• Use Geneva Conventions terminology accurately.

Key Takeaways