Internal or Non-international Armed Conflict (NIAC) under International Humanitarian Law

1. Definition and Legal Framework An internal or non-international armed conflict (NIAC) refers to armed hostilities that take place within the borders of a single state, involving the government and organized armed groups, or between such groups themselves, without the direct involvement of other states. It is distinct from international armed conflicts (IACs) which involve multiple states.

The legal framework for NIACs is primarily derived from two key sources under International Humanitarian Law (IHL):

Common Article 3 of the 1949 Geneva Conventions: Common Article 3 sets out minimum standards of humane treatment for persons not taking an active part in hostilities, including civilians and combatants who are hors de combat (wounded, captured, or otherwise incapacitated). It applies in all NIACs and is often referred to as a "mini-convention" within the broader Geneva Conventions.
Additional Protocol II (AP II) to the Geneva Conventions of 1977: AP II supplements Common Article 3 and provides more detailed rules for the protection of civilians and combatants. It only applies in situations where the armed groups are organized and control a significant portion of territory, enabling them to carry out sustained military operations.

2. Threshold for a Non-international Armed Conflict A crucial distinction between a mere internal disturbance (e.g., riots, isolated violence) and a NIAC under IHL is the level of intensity and organization of the parties involved. For an internal conflict to rise to the level of a NIAC, two main criteria must be satisfied:

Intensity of the Conflict: The hostilities must surpass mere internal disturbances or tensions, reaching a threshold of sustained armed violence.
Organization of the Parties: The non-state armed groups must have a level of organization that allows them to engage in coordinated military operations. This includes having a command structure, capacity for planning operations, and ability to implement IHL.

The International Criminal Tribunal for the former Yugoslavia (ICTY) has provided a working definition of NIAC in its Tadić case, specifying these criteria for recognizing the existence of a NIAC.

3. Legal Protections in NIACs Both Common Article 3 and AP II emphasize the humane treatment of individuals during NIACs. These protections include:

Protection of Non-Combatants: Civilians and those not directly participating in hostilities must be treated humanely. Acts such as murder, torture, mutilation, cruel treatment, and taking hostages are prohibited.
Protection of the Wounded, Sick, and Shipwrecked: Parties to the conflict are obligated to collect and care for the wounded and sick without adverse distinction. Medical personnel and facilities must also be respected.
Humane Treatment of Detainees: Detainees, whether combatants or civilians, are entitled to humane treatment. Executions without a proper trial and degrading treatment are prohibited.
Prohibition of Indiscriminate Attacks: Attacks against civilian populations or civilian objects are strictly forbidden. AP II also prohibits acts of terror against civilians and prohibits starvation as a method of warfare.

4. Key Principles Governing NIACs The following core principles of IHL govern NIACs, similar to their application in international armed conflicts:

Principle of Distinction: Parties must always distinguish between civilians and combatants. Only combatants may be targeted.
Principle of Proportionality: Even if an attack is directed against a legitimate military target, the attack must not cause excessive civilian harm relative to the anticipated military advantage.
Principle of Military Necessity: Military operations must serve a legitimate military purpose, and the harm caused must be proportional to the objective.
Principle of Humanity: Parties to the conflict must ensure that suffering is minimized, especially for those who are no longer participating in hostilities, such as the wounded, detainees, and civilians.

5. International Criminal Responsibility Individuals, including military commanders and political leaders, can be held criminally responsible for war crimes committed during a NIAC. The Rome Statute of the International Criminal Court (ICC) recognizes the commission of war crimes in NIACs, including:

Murder, torture, and inhuman treatment.
Attacks against civilians.
Pillage and destruction of civilian property.
Sexual violence, including rape.
Forced displacement of civilian populations.

The ICC’s jurisdiction over NIACs is significant as it broadens accountability for violations of IHL, particularly in conflicts involving non-state actors.

6. Domestic Application of NIAC Rules in the Philippines In the Philippines, non-international armed conflicts have historically involved the state and non-state armed groups such as the New People’s Army (NPA), the Moro Islamic Liberation Front (MILF), and the Abu Sayyaf Group (ASG). These conflicts have triggered the application of NIAC norms under both Common Article 3 and AP II, to which the Philippines is a party.

Republic Act No. 9851 (Philippine Act on Crimes Against International Humanitarian Law, Genocide, and Other Crimes Against Humanity) incorporates IHL provisions into domestic law. It defines and penalizes war crimes committed during non-international armed conflicts, such as attacks on civilians, torture, and inhuman treatment.
The 2009 Internal Peace and Security Plan (IPSP): The Armed Forces of the Philippines (AFP) acknowledges the applicability of IHL, particularly Common Article 3 and AP II, in its counter-insurgency operations. The plan also emphasizes adherence to human rights laws alongside IHL norms.

7. Challenges and Evolving Issues in NIACs

Classification Challenges: Determining whether an internal conflict meets the threshold of a NIAC can be contentious, as states often resist the classification of an internal situation as a NIAC, as it implies international oversight and legal obligations.
Application to Non-State Actors: A central challenge is ensuring non-state armed groups comply with IHL. Although IHL binds these groups, enforcing accountability, particularly against splinter or loosely organized groups, remains difficult.
Urban Warfare and Asymmetric Conflicts: NIACs increasingly involve urban settings, complicating the application of distinction and proportionality principles. Asymmetric tactics by non-state actors, such as the use of civilians as shields, pose significant challenges to ensuring compliance with IHL.

8. Conclusion Non-international armed conflicts (NIACs) are subject to specific rules and protections under International Humanitarian Law, primarily through Common Article 3 and Additional Protocol II to the Geneva Conventions. These provisions set out minimum standards for the treatment of individuals and the conduct of hostilities, aiming to limit the effects of armed conflict on civilian populations and non-combatants. The domestic application of these rules, as seen in the Philippines, underscores the evolving challenges of applying IHL to conflicts involving non-state actors, while ensuring compliance and accountability.