Combatant

A combatant is a person who takes a direct part in the hostilities of an armed conflict. If a combatant follows the law of war, then he or she is considered a privileged combatant and upon capture, he or she will qualify as a prisoner of war under the Third Geneva Convention (GCIII). An unprivileged combatant is a person, such as a mercenary, who takes a direct part in the hostilities but who upon capture does not qualify for prisoner-of-war status.

The following categories of combatants qualify for prisoner-of-war status on capture:

For countries which have signed the "Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts" (), combatants who do not wear a distinguishing mark still qualify as prisoners of war if they carry arms openly during military engagements, and while visible to the enemy when they are deploying to conduct an attack against them.

There are several types of combatants who do not qualify as privileged combatants:

If there is any doubt as to whether the person benefits from "combatant" status, they must be held as a POW until they have faced a "competent tribunal" (GCIII Art 5) to decide the issue.

Most unprivileged combatants who do not qualify for protection under the Third Geneva Convention do so under the Fourth Geneva Convention (GCIV), which concerns civilians, until they have had a "fair and regular trial". If found guilty at a regular trial, they can be punished under the civilian laws of the detaining power.

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