Combatant is a term of art that describes the legal status of an individual who has the right to engage in hostilities during an international armed conflict. The legal definition of "combatant" is found at article 43 of Additional Protocol One to the Geneva Conventions of 1949 [AP1]. It states that "Members of the armed forces of a Party to a conflict (other than medical personnel and chaplains covered by Article 33 of the Third Convention) are combatants, that is to say, they have the right to participate directly in hostilities." 
In addition to having the right to participate in hostilities, combatants have the right to status of Prisoners of War when captured during an international armed conflict.  " While all combatants are obliged to comply with the rules of international law applicable in armed conflict, violations of these rules shall not deprive a combatant of his right to be a combatant or, if he falls into the power of an adverse Party, of his right to be a prisoner of war."
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" (Protocol I), 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.
Manage research, learning and skills at defaultLogic. Create an account using LinkedIn or facebook to manage and organize your Digital Marketing and Technology knowledge. defaultLogic works like a shopping cart for information -- helping you to save, discuss and share.