International humanitarian law of non-international armed conflicts contains no reference to combatants or prisoners of war. Rather, the term “fighters” is used by scholars and practitioners to refer to members of armed groups, often only if they perform a continuous fighting function. For the purpose of conduct of hostilities, the term reflects a status-based equivalent of the notion of combatants in international armed conflicts. “Fighters” may thus be targeted at all times, subject, according to some, to the principle of military necessity.
However, fighters do not have combatant immunity, and therefore, can be prosecuted for directly participating in hostilities.
Fighters who have fallen into the hands of the adversary are entitled to the same protection as civilians (GC I-IV, Art. 3; P II, Art. 4).
See Armed groups; Non-international armed conflict; Combatants; Direct Participation in Hostilities;
CASES
ICRC, International Humanitarian Law and the challenges of contemporary armed conflicts in 2015 [paras 84-87, 91, 92]
Mali, Accountability for the Destruction of Cultural Heritage
United Kingdom, The Case of Serdar Mohammed (Court of Appeal and Supreme Court Judgments)
El Salvador, Supreme Court Judgment on the Constitutionality of the Amnesty Law
Syria, Report by UN Commission of Inquiry (March 2017)
ICC, Confirmation of Charges against LRA Leaders
Eastern Ukraine, OHCHR Report on the Situation: November 2016 - February 2017
UN, Working Group on the use of Mercenaries: Preliminary Findings of Mission to Ukraine
Iraq, Crimes by Militia Groups
Central African Republic, No Class: When Armed Groups Use Schools
Mexico, Recapture of Ovidio Guzmán, One of the Leaders of the Sinaloa Cartel