Principle of Distinction in International Humanitarian Law

The principle of distinction requires parties to an armed conflict to distinguish persons and objects that may lawfully be attacked from those protected against attack. Operations must therefore be directed only against combatants and military objectives, and not against civilians or civilian objects.

Core requirements

The rule governs both the selection of targets and the manner in which attacks are conducted. It is recognised as a rule of customary international humanitarian law applicable in international and non-international armed conflicts.

• Attacks must not intentionally target civilians or the civilian population.
• Attacks may be directed only against military objectives, not civilian objects.
• Indiscriminate attacks are prohibited because they are not directed at a specific military objective or cannot be limited as international humanitarian law requires.

Who and what may be targeted

Under Article 52(2) of Additional Protocol I, an object is a military objective only if it effectively contributes to military action by its nature, location, purpose or use, and its destruction, capture or neutralisation offers a definite military advantage in the circumstances ruling at the time.

• A civilian enjoys protection against direct attack unless, and only for such time as, the civilian directly participates in hostilities.
• Where there is doubt whether a person is a civilian, Article 50(1) requires that person to be considered a civilian.
• A normally civilian object may become a military objective only when the applicable definition is satisfied.

Related operational duties

Distinction works with the separate principles of precautions in attack and proportionality. Parties must verify targets, choose feasible means and methods to reduce civilian harm, and cancel or suspend an attack when its unlawfulness becomes apparent.

• Civilian presence does not remove the duty to distinguish between lawful targets and protected persons or objects.
• Distinction does not prohibit every incidental civilian injury, but deliberate attacks on civilians remain unlawful.