Non-international Armed Conflict (NIAC) | The Practical Guide to Humanitarian Law

International humanitarian law defines and regulates only two categories of armed conflict. It uses the term non-international armed conflict to denote very diverse situations, both in terms of the form and the objective of armed confrontations. This term is used as opposed, on the one hand, to the category of international armed conflict and, on the other, to the category of internal disturbances and tensions, which are excluded from the definition of armed conflicts.

It replaces and includes the notions of internal armed conflict, civil war, rebellion, and insurrection, which are not specific categories defined and recognized by humanitarian law. The definition of a non-international armed conflict poses political as well as legal questions. Such conflicts feature a very strong political, legal, and military asymmetry. Indeed, confrontations bring into opposition, on one side, the army and national law enforcement apparatus and, on the other, individuals and dissident or non-state armed groups, who are more or less organized and considered criminals by national law. The national State whose authority and sovereignty is being attacked from the inside is naturally reluctant to acknowledge the status of adversary to those who threaten its power. The State concerned will in most cases be tempted to deny the existence of a conflict and to invoke instead a situation of disturbance that will legally allow it to criminalize the actions of the armed opposition groups and to mobilize the whole law enforcement and national military apparatus in the name of public order. Indeed, in situations of internal disturbances and tensions, humanitarian law does not yet apply, and the right to recourse to force by the State is limited only by international human rights conventions, whose immediate effectiveness remains limited.

The definition of the threshold that distinguishes situations of internal disturbances or tensions from those of non-international armed conflict is a major political and legal issue, as it is the definition of non-international armed conflict that triggers the implementation of humanitarian law. This law allows for the establishment of limits in the recourse to force by the State and open the right to assistance and protection for the victims of these situations. It also allows the mitigation of the strong legal asymmetry that characterizes such situations.

The definition and qualification of this type of conflict is important as it allows for the application of rules of conventional humanitarian and customary law relating to non-international armed conflict. It is the intensity of combat and the organization of the armed groups that marks the distinction between a conflict and a situation of internal disturbances or tensions. These objective criteria aim to avoid the State concerned denying the existence of an armed conflict on its territory in order to free itself from adhering to humanitarian law in the use of armed force.
The qualification of conflict does not belong to the parties to the conflict but rather depends on objective criteria set by the Geneva Conventions and their Additional Protocols.
A non-international armed conflict can be internationalized if a non-state armed group in fact acts under the control or on behalf of a foreign State.
Situations of internal disturbances or tensions such as riots, isolated and sporadic acts of violence, and other analogous acts are not considered armed conflicts (APII Art.1). However, even in these situations, the fundamental guarantees contained in the fundamental principles of human rights and in the principles of Common Article 3 to the Geneva Conventions are still applicable.

Non-international armed conflicts are provided for and governed by Common Article 3 to the four Geneva Conventions of 1949 and by the Additional Protocol II of 1977 to the Geneva Conventions, which contains twenty-eight articles that complete the guarantees of Common Article 3 for the victims of non-international armed conflicts.

The lack of a common legal definition between the 1949 Common Article 3, the 1977 Additional Protocol II, and the jurisprudence of the International Criminal Tribunals has produced a profusion of technical legal commentaries that must be prioritized and summarized. Indeed, the definition of non-international armed conflict is the subject of intense legal debates fed by international jurisprudence, by the diversity of the forms of conflicts since the end of the Cold War and the global war on terror, as well as by the multiplication of non-state armed groups (I; II). This qualification determines the law applicable to these situations (III).

It is crucial to be able to qualify and define this kind of conflict so as to trigger the implementation and enforcement of the rules of humanitarian law foreseen for non-international armed conflicts. The level of intensity of the fighting establishes the distinction between a situation of conflict and one of internal disturbance or tension.

Situations of internal disturbance and tension, such as riots, isolated and sporadic acts of violence, and other acts of a similar nature, are not considered to be armed conflicts (APII Art. 1). However, even in such circumstances, the principles of Common Article 3 to the Geneva Conventions, as well as the protection of inalienable human rights, remain in force.

➔ Fundamental guarantees; Inalienable rights; Internal disturbances and tensions

Conventional Definition

Common Article 3 contains the minimum guarantees applicable in armed conflicts that do not have an international character. This Article does not provide any specific definition of this type of armed conflict. It is a negative definition that aims to cover all forms of armed conflicts that cannot be qualified as international and are therefore not covered by the other provisions of the Geneva Conventions. Common Article 3 provides no definition of non-international armed conflict or of internal disturbances or tensions that would allow for the demarcation of the limit between these two types of situation. This, of course, is not an oversight but rather a legal strategy designed to preserve the application of these fundamental guarantees from all possible controversy relating to the qualification of the situation.

Article 1 of Additional Protocol II, on the contrary, conducts a descriptive statement of non-international armed conflict, specifying that non-international armed conflict is distinguished from international armed conflict and from situations of internal disturbances or tensions that are excluded from the definition and regulation of armed conflicts. This descriptive statement has resulted in an intense activity of legal interpretation of each mentioned criterion, which has, in return, dangerously and unnecessarily complicated the qualification of non-armed international conflicts.

Article 1.1 of Additional Protocol II first of all states that the Protocol completes Common Article 3 without modifying its conditions of application. This therefore means that none of the criteria set out in the rest of the definition of Additional Protocol II may be invoked to contest the application of Common Article 3 to situations that would not meet the said criteria (infra).
Article 1.1 states that it is applicable to all conflicts that are not considered international “and which take place on the territory of a High Contracting Party between its armed forces and dissident armed forces or other organised armed groups which, under responsible command, exercise such control over a part of its territory as to allow them to carry out sustained and concerted military operations and to implement this Protocol.”
Article 1.2 of Additional Protocol II concludes this definition of non-international armed conflict by stating that it “does not apply to situations of internal disturbance and tension, such as riots, isolated and sporadic acts of violence and other acts of a similar nature, which are not considered armed conflicts.” This last provision of Article 1, by negation, adduces the threshold for the intensity of the violence that constitutes the definition of a non-international armed conflict as opposed to internal disturbances and tensions. The notion of “riots” and “sporadic and isolated acts of violence” is seen here as opposed to acts of violence that would be continuous, large-scaled, or organized depending on whether the word “isolated” refers to the territorial or human element. The threshold of violence has therefore a double dimension: territorial and temporal. It clearly implies acts of violence that are continuous and established in time. This criterion of duration has been acknowledged by international jurisprudence (infra).

These two territorial and temporal criteria are complemented by a third relating to the organized character of non-state armed groups, which must dispose of a responsible command and be able to carry out concerted and sustained military operations.

Besides the issue of the intensity of violence, the definition also refers to a series of material elements such as the territoriality of the conflict, the organization of non-state armed groups, the type of command of these groups, the control of a part of the territory by these groups, the continuity and coordination of the military operations of these groups and their capacity to comply with humanitarian law. The interpretation of these criteria creates certain difficulties. Some see them as objective descriptive elements that allow for the distinction of armed conflict from situations of internal disturbance and tensions, defined as sporadic and isolated acts of violence. Others see them rather as the imperative and cumulative legal criteria prerequisite to any invoking or application of Additional Protocol II. This literal and cumulative interpretation of the elements of the definition leads to absurd results. In this manner, Additional Protocol II could not, for example, be applied to situations where non-international conflict would spread out over the territory of several State parties or would involve transnational armed groups or foreign groups that are not attached to the State party to the conflict.

International law imposes rules of interpretation of the treaties in accordance with the intention of the authors and in line with their objective. It opposes any interpretation that may lead to an absurd result or one which would be contrary to the objective of the text (infra).

The objective of the definition contained in Additional Protocol II was to dispose of objective criteria that would permit a solution to the historic reticence of some States to recognize the existence of an armed conflict on their national territory and the rights of its victims. It would appear, however, that, apart from the threshold of the intensity of violence, which retains an objective aspect, the rest of the criteria of the definition pertain to subjective interpretation and necessitate the availability of material information that may either delay or render impossible the implementation of Additional Protocol II. This is particularly so for the criteria relating to the existence of a responsible command, the organized character of the armed groups, or control of territory.

This is against the spirit of humanitarian law, which consists of establishing the applicable law from the very beginning of a conflict and avoiding the possibility that parties to the conflict control the definition of the conflict. It would therefore seem logical to consider that these elements do not constitute prerequisite conditions to the qualification of non-international armed conflict and the application of Additional Protocol II.

The decisions of the International Criminal Tribunals were able to specify the interpretation of the criteria contained in the definition of Additional Protocol II. Jurisprudence has allowed in certain cases the reestablishment of the interpretation of this definition that remains in compliance with the spirit of the 1949 Geneva Conventions and the two 1977 Additional Protocols.However, the arguments of the International Criminal Tribunals must be considered with caution as they did not intend to qualify the conflict as such but to define the applicable war crimes. Yet criminal law is subject to strict rules of interpretation, as opposed to humanitarian law, which must be applied as broadly as possible. Similarly, the concept of non-state armed groups has been the object of important developments in the framework of international jurisprudence as one criterion of the internationalization of armed conflicts and not as an element of qualification of non-international armed conflict.

Definition in Jurisprudence

International and national tribunals have maintained and specified the criteria of duration, organization, and intensity. They do not apply these criteria in a strict and cumulative way but use them with the sole objective of distinguishing non-international armed conflict from internal disturbances, banditry, and unorganized insurrection. They provide an interpretation of the definition of non-international armed conflict in accordance with the spirit of these conventions. They discredit the abusive interpretations developed by certain States that create legal black holes in the management of armed conflict and prevent the implementation of humanitarian law. They also clarify the criteria and the conditions of the internationalization of internal conflict. These elements, introduced in the framework of different judgments handed down by the International Criminal Tribunal for Former Yugoslavia in the Tadic Case , have been taken up and developed by subsequent jurisprudence.

Criteria of Intensity and Organization

In the Tadic Case (IT-94-1-T, 7 May 1997), the ICTY Trial Chamber decided that

an armed conflict exists whenever there is a resort to armed force between States, protracted armed conflict between governmental authorities and organized armed groups or between such groups within a State (para. 561).

To determine the existence of a non-international armed conflict in the sense of the Common Article 3 to the Geneva Conventions, it is necessary to examine two elements of the conflict: its intensity and the organization of the parties to the conflict.

In an armed conflict of an internal or mixed character, these closely related criteria are used solely for the purpose, as a minimum, of distinguishing an armed conflict from banditry, unorganized and short-lived insurrections, or terrorist activities, which are not subject to international humanitarian law” (para. 562).

This interpretation is confirmed in the Musema Case (ICTR) and thr Boskovski Case (ICTY) (infra Jurisprudence).

The jurisprudence has therefore retained a minimum level of organization in non-international armed conflict. This minimal criterion should not be confused with the legal debates that surround the role and status of non-state armed groups in the internationalization of conflict.

➔ International armed conflict; Non-state armed groups

Criterion of Duration and Criterion of Intensity

The criterion of protracted armed violence has therefore been interpreted in practice, including by the Tadić Trial Chamber itself, as referring more to the intensity of the violence rather than its duration. Trial Chambers have relied on indicative factors relevant for assessing the “intensity” criterion, none of which are, in themselves, essential to establish that the criterion is satisfied. These indicative factors include the number, duration and intensity of individual confrontation; the type of weapons and other military equipment used; the number and calibre of munitions fired; the number of persons and type of forces partaking in the fighting; the number of casualties; the extent of material destruction; and the number of civilians fleeing combat zones. The involvement of the UN Security Council may also be a reflection of the intensity of a conflict. (ICTY, Haradinaj Case , IT-04-84-T, Judgment, 3 April 2008, para. 49)

Various indicative factors have been taken into account by Trial Chambers to assess the “intensity” of the conflict. These include the seriousness of attacks and whether there has been an increase in armed clashes, the spread of clashes over territory and over a period of time, any increase in the number of governmental forces and mobilization and the distribution of weapons among both parties to the conflict, as well as whether the conflict has attracted the attention of the United Nations Security Council, and whether any resolutions on the matter have been passed. Trial Chambers have also taken into account in this respect the number of civilians forced to flee from the combat zones; the type of weapons used, in particular the use of heavy weapons, and other military equipment, such as tanks and other heavy vehicles; the blocking or besieging of towns and the heavy shelling of these towns; the extent of destruction and the number of casualties caused by shelling or fighting; the quantity of troops and units deployed; the existence and change of front lines between the parties; the occupation of territory, and towns and villages; the deployment of government forces to the crisis area; the closure of roads; cease-fire orders and agreements, and the attempt of representatives from international Organizations to broker and enforce cease-fire agreements. (ICTY, Boskoski Case , IT-04-82-T, 10 July 2008, para. 177)

Criterion of Interpretation

According to the case law, these criteria of qualification of conflict cannot be left to the assessment of the parties to the conflict. The jurisprudence recalls that

the main objective of the four Geneva Conventions, as well as the two Protocols thereto, is to protect the potential victims of armed conflict. If the implementation of international humanitarian law depends on the sole subjective interpretation of the parties to conflicts, they will tend to minimize its intensity. So, on the basis of objective criteria, Common Article 3 and the Additional Protocol II will be applicable as long as it is established that there is an internal armed conflict that satisfies their pre-established respective criteria. (ICTR, Akayesu Case , ICTR-96-4-T, 2 September 1998, para. 624)

This is why the definition of conflict does not take into account the subjective considerations of the parties on the nature of the conflict but is based instead upon objective criteria relative to the nature and extent of recourse to armed force.

The War on Terror: Not a Third Category of Armed Conflict

In Hamdam v. Rumsfeld , the Supreme Court of the United States rejected the improper interpretation of the criteria of qualification of conflicts used by the American authorities to refuse the guarantees of Common Article 3 to certain detainees of the war on terror. By relying upon a literal interpretation of the Geneva Conventions, the American government claimed that the armed conflict with Al Qaeda was not covered by any provision of international humanitarian law, not even by Common Article 3. They claimed that the conflict was not international because there was no opposition between two State entities but neither was it non-international as it was located on the territory of several States. This interpretation was in contradiction to the spirit and the object of the texts it claimed to serve and led to the absurd opposition of the legal provisions designed to complement them. It created legal black holes, whereas international humanitarian law had on the contrary established a legal continuity able to cover the full diversity of the situations of armed conflict.

The Supreme Court recalled that the notion of non-international armed conflict is used in Common Article 3 as opposed to armed conflict between nations regulated by Common Article 2 to the Geneva Conventions. It stated that the Common Article 3 must be interpreted in a literal manner and in the spirit of its authors, who removed all of the terms that could have limited its field of application in the final version of the text. This Article offers a minimal protection, which has nothing to do with the one foreseen by the conventions, to individuals associated to a signatory State or not. Its field of application is very large, but the offered rights are more limited (Supreme Court of the United States, 05-184, Salim Ahmed Hamdam, petitioner v. Donald H. Rumsfeld, Secretary of Defense, et al., on Writ of Certiorari to the U.S. Court of Appeals for the District of Columbia Circuit , 29 June 2006, pp. 65–69).

In a verdict from 2006, the Supreme Court of Israel also rejected similar arguments by the Israeli government concerning the fact that a war between a State and terrorist organizations or individuals would constitute a third legal category of conflict beyond the remit of international humanitarian law applicable to international and non-international armed conflicts. The judge declared that the question that had to be addressed did not concern the expedient law but the existing law. In this framework, the Court confirmed that the existing law did not foresee this third category of armed conflict ( Supreme Court Sitting as the High Court of Justice, HCJ 769/02, the Public Committee against Torture in Israel , 11 December 2005, paras. 27, 28).

➔Terrorism

These decisions have thus served as a useful reminder that international humanitarian law recognizes only two types of armed conflict: international and non-international. Therefore, the elements of the definition and the existing criteria of qualification of these two types of conflicts cannot be used or interpreted to create new categories of conflict that are not covered by international humanitarian law. The work of description and of typology of the current forms of armed conflict is useful to understand the particular forms of confrontation unique to each context, but cannot create new legal categories that would fall outside the scope of humanitarian law (concerning the rules of interpretation of international law, see also ➔ International law ).

Criteria of Internationalization of Noninternational Armed Conflict

International jurisprudence has also introduced the non-conventional notion of “internationalized” armed conflict. In the Tadic Case (IT-94-1-A, 15 July 1999, para. 84), the Appeals Chamber stated that a non-international armed conflict can be “internationalized” on the basis of criteria that attest to the role of a foreign State or of its de facto control on certain armed groups.

➔ International armed conflict

Taking into account the complexity of current conflicts, the doctrine recognizes that a situation of armed conflict can be constituted by the superposition of several simultaneous conflicts, each defined by the State or non-state nature of the forces party to the conflict. This doctrine has led to the fragmenting of the application of humanitarian law in one same context and on the same territory in conflict. The impact of this system is nonetheless limited by the unification of the rules applicable to international and non-international armed conflict, notably through the drafting of customary laws of international humanitarian law by the ICRC in 2005.

Applicable Law in Noninternational Armed Conflict

The applicable rules of international humanitarian law to non-international armed conflict are contained in:

Common Article 3 to the four Geneva Conventions of 1949;
The second Additional Protocol to the Geneva Conventions of 1977 (“Additional Protocol II”);
Customary international humanitarian law

International humanitarian law limits the means and methods of warfare during non-international armed conflicts and organizes the protection and relief of the civilian population. It also foresees a right to humanitarian initiative in favor of any impartial humanitarian organization to allow it to implement relief operations (GCI-IV Common Art. 3; GCI, GCII, GCIII Art. 9; GCIV Art. 10; APII Art. 18.2).

Based on the fact that Common Article 3 and Additional Protocol II do not use the same definition of non-international armed conflict, some authors consider that there are two different types of non-international armed conflicts. Conflicts that do not meet all the criteria of Additional Protocol II would therefore not be covered by Common Article 3 only. While Additional Protocol II would only be applicable in situations where all the criteria of the definition are fulfilled, in particular those relating to the organization of non-state armed groups and to their control of a part of the territory. This position comes from a legalism that is contrary to the spirit and the letter of humanitarian law. Humanitarian law has foreseen and regulated only two categories of armed conflict: international and non-international.

When Additional Protocol II refers to actions of armed groups that act (1) under responsible command and (2) exercise such control over a part of its territory as to enable them (3) to carry out sustained and concerted military operations and to apply this Protocol, it aims first of all to distinguish situations of conflict from simple internal unrest or insecurity in which confrontations are not structured, organized, or planned by one or several identifiable commands.

Additional Protocol II recalls that a non-state armed group conducting military operations has organizational obligations that must include discipline and respect for IHL in its own actions of combat. This non-state armed group is effectively subject to compliance with the same obligations as the State, although it may dispose of very different capabilities. In this way, for example, the obligations relating to detention are greatly dependent upon the capacity of the non-state group to control a part of the territory. The criteria of organization of non-state armed groups contained in Additional Protocol II are therefore not designed to modify the qualification of non-international armed conflict nor the resulting obligations for the State in question. They are designed to recall the obligation of organization that is upon the non-state armed group and to adjust the level of responsibility of individuals and the command of this group in violations of humanitarian law to its level of organization. If the organization of the non-state armed group is flawed, the State will nevertheless not be freed from its own obligations to respect Additional Protocol II.

On a practical level, it is important to recall that Common Article 3 escapes the constraints of conventional application of humanitarian law. It invites the parties to the conflict to put into place all or some of the conventions by way of special agreement from the very beginning of the conflict.

➔ Special Agreement

The rules foreseen for non-international conflict are less numerous and detailed than those relating to international armed conflict. Common Article 3 is supplemented by Additional Protocol II, which totals only twenty-eight articles. However, the development of rules of customary international humanitarian law shows a clear tendency toward the harmonization of the content of the rules applicable to these two types of conflicts, as much in regard to the limitation of the methods of warfare as to the right to assistance and protection for the population. The customary international humanitarian law study (customary IHL study) published by the ICRC in 2005 on this subject identifies 161 rules of customary international humanitarian law, of which 147 are common to international and non-international armed conflicts. This harmonization limits the pertinence of the textual obsession linked to the definition of armed conflicts contained in Additional Protocol II.

The jurisprudence of international tribunals has greatly contributed to this customary evolution in order to align the rules of humanitarian law applicable in non-international armed conflict with those established for international armed conflict. Hence, it is largely accepted today that the more detailed rules relating to international conflict can serve as a framework for the interpretation of the general principles established for internal conflict or can be applied by analogy to these conflicts.

In 1995, the International Criminal Tribunal for the Former Yugoslavia expressed the view that

in the area of armed conflict the distinction between interstate wars and civil wars is losing its value as far as human beings are concerned. Why protect civilians from belligerent violence, or ban rape, torture or the wanton destruction of hospitals, churches, museums or private property, as well as proscribe weapons causing unnecessary suffering when two sovereign States are engaged in war, and yet refrain from enacting the same bans or providing the same protection when armed violence has erupted “only” within the territory of a sovereign State? If international law, while of course duly safeguarding the legitimate interests of States, must gradually turn to the protection of human beings, it is only natural that the aforementioned dichotomy should gradually lose its weight. (ICTY, Tadic Case , Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction , 2 October 1995, paras. 97, 199, and 125)

This tendency toward the unification of international humanitarian law applicable to both types of armed conflict has primarily expressed itself in the framework of international criminal law relating to war crimes. Although the definition of war crimes has only existed in international armed conflicts since 1949, violations of Common Article 3 have been recognized as crimes by international jurisprudence in 1995 (ICTY, Tadic Case , cf. infra). Since then, the Rome Statute of the International Criminal Court adopted in 1998 has allowed for the legal void that surrounded the international definition and repression of war crimes committed during armed internal conflict to be filled. The definitions of war crimes contained in the Rome Statute for both types of armed conflicts are now very similar (Art. 8.2.a and b IAC; Art. 8.2.c–f NIAC).

The main difference between international armed conflicts and those of a non-international character is in the structural and legal asymmetry of the latter. Provided that international law is mainly drafted by States, it is particularly difficult to maintain a legal balance between the rights of the State and those of non-state armed groups that challenge its power by force. The status of combatants belonging to non-state armed groups constitutes the main political and legal problem in this type of conflict. Indeed, in such context, humanitarian law coexists with domestic law, which maintains the prerogatives and obligations of the authorities and the governmental forces.

This is why the complementarity between humanitarian law and human rights law is mentioned in the preamble of Additional Protocol II. The international conventions relative to human rights remain in force in times of conflict (apart from authorized derogations) to guarantee the general protection of the population by their own State and particularly the fate of those who take part in hostilities.

The complementary and simultaneous application of international humanitarian law and human rights law must also allow for a transition between situations of internal disturbances and tensions and those of non-international armed conflict.

The main rules of humanitarian law have therefore been transposed to this type of conflict: limitation of the methods of combat; protection of the civilian population; fundamental guarantees; protection of medical, religious, and relief personnel; the right to impartial aid for the civilian population deprived of goods essential to their survival; respect for the impartiality of the medical mission and medical care to the wounded and sick; judicial guarantees for the repression of violations related to the conflict; and specific guarantees for all persons deprived of their liberty for reasons related to the conflict.

However, the combatant status provided for international conflicts has not been transposed to non-international armed conflicts. The status of those who take up arms against their own State, whether individually or within non-state armed groups, is still subject to the application of the national law of the country in question. This means that there are no combatant privileges (i.e., prisoner-of-war status) in this type of conflict and that the individuals or the members of armed groups who participate in the hostilities against governmental forces are guilty of criminal activities before the national law. They enter the category of civilians directly participating in the hostilities, and as such they become legitimate targets during and for such time as they directly participate in the hostilities. If they are wounded or captured by the governmental forces, Additional Protocol II provides guarantees of treatment, guarantees for individuals deprived of their liberty in relation to the conflict, and judicial guarantees in case of criminal prosecution in relation to the conflict (Art. 6). It is possible, with the consent of the parties to the conflict and by way of special agreement, to extend by analogy some provisions of humanitarian law relating to combatants in international armed conflicts to individuals taking up arms in non-international armed conflicts. The status of persons belonging to non-state armed groups also arises in certain types of international armed conflicts and are foreseen by Additional Protocol I (Arts. 43–45).

➔ Civilians; Combatants; Human rights; Internal disturbances and tensions; Non-state armed groups

⚖ Jurisprudence

In the Tadic Case (IT-94-1-A, 15 July 1999, para. 84), the ICTY Appeals Chamber stated that a non-international armed conflict may be “internationalized” on the basis of criteria that attest the role of a foreign State or of its de facto control on certain armed groups.

➔ International armed conflict

In the Musema Case (ICTR-96-13-T, 27 January 2000), the ICTR Trial Chamber stated that

a non-international conflict is distinct from an international armed conflict because of the legal status of the entities present: the parties to the conflict are not sovereign States, but the government of one and the same single State in conflict with one or more armed factions within its territory. The expression “armed conflicts” introduces a material criterion: the existence of open hostilities between armed forces which are organized to a greater or lesser degree. (paras. 247–48)

In the Boskovski Case (IT-04-82-T, 10 July 2008), the ICTY Trial Chamber II detailed the two criteria of intensity of the conflict and organization of the armed groups necessary to qualify a conflict as being non-international:

The criterion of intensity of the conflict (para. 177): In order to assess this intensity, the Tribunal examined the following criterion: the seriousness of attacks and whether there has been an increase in armed clashes, the spread of clashes over territory and over a period of time, any increase in the number of governmental forces and mobilization and the distribution of weapons among both parties to the conflict, as well as whether the conflict has attracted the attention of the United Nations Security Council, and whether any resolutions on the matter have been adopted. The Tribunal also takes into account the number of civilians forced to flee from the combat zones; the type of weapons used, in particular the use of heavy weapons, and other military equipment, such as tanks and other heavy vehicles; the blocking or besieging of towns and the heavy shelling of these towns; the extent of destruction and the number of casualties caused by shelling or fighting; the quantity of troops and units deployed; the existence and change of front lines between the parties; the occupation of territory and towns and villages; the deployment of governmental forces in the crisis area; the closure of roads; cease-fire orders and agreements; and the attempt of representatives from international organizations to negotiate and enforce cease fire agreements.
The criterion of organization of armed groups (paras. 199–203): The Tribunal took into account a number of factors when assessing the organization of an armed group, and these fall into five broad groups. These factors indicate the various levels of organization and control but they do not intend to set criteria for definition of non-international armed conflicts included in Additional Protocols II.
The first group signals the presence of a command structure , such as the establishment of a general staff or high command, which appoints and gives directions to commanders, disseminates internal regulations, organizes the supply of weapons, authorizes military action, assigns tasks, issues political statements and communiqués, and is informed by the operational units of all developments within the unit’s area of responsibility. Also included in this group are factors such as the existence of internal regulations setting out the organizational structure of the group, the assignment of an official spokesperson, and communication through communiqués.
The second group of factors indicates the ability to carry out military operations in an organized manner . Several criteria have been considered, such as the group’s ability to determine a unified military strategy and to conduct large-scale military operations, the capacity to control a part of the national territory, the capacity of operational units to coordinate their actions, and the effective dissemination of written and oral orders and decisions.
The third group concerns factors indicating the level of logistics , such as the ability to recruit new members and to provide military training, the supply of weapons, the supply and use of uniforms, and the existence of communications equipment for linking headquarters with units or between units.
In a fourth group, factors relevant to determining whether an armed group possesses a level of discipline and the ability to implement the basic obligations of Common Article 3 have been considered, such as the establishment of disciplinary rules and codes of conduct.
A fifth group includes those factors indicating that the armed group was able to speak with one voice , such as its capacity to act on behalf of its members in political negotiations with representatives of international organizations and foreign countries, and its ability to negotiate and conclude agreements such as cease-fires or peace accords.
Law applicable to non-international armed conflicts.

The rulings of the International Criminal Tribunals have partially unified the rules applicable to international and non-international conflicts, in particular in the area of crime repression.

In the Tadic Case ( Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction , 2 October 1995), the ICTY Appeals Chamber made an important jurisprudential development relating to the applicable law to non-international armed conflicts. The tribunal listed the provisions of customary character applicable to non-international conflicts and stated that “what is inhumane, and consequently proscribed, in international wars, cannot but be inhumane and inadmissible in civil strife” (para. 119). The Tribunal notes that “State practice shows that general principles of customary international law have evolved with regard to internal armed conflict also in areas relating to methods of warfare” (para. 125). It pointed out that “only a number of rules and principles governing international armed conflicts have gradually been extended to apply to internal conflicts; and this extension has not taken place in the form of a full and mechanical transplant of those rules to internal conflicts; rather, the general essence of those rules, and not the detailed regulation they may contain, has become applicable to internal conflicts” (para. 126). The Tribunal stated that

notwithstanding these limitations, it cannot be denied that customary rules have developed to govern internal strife. These rules, as specifically identified in the preceding discussion, cover such areas as protection of civilians from hostilities, in particular from indiscriminate attacks, protection of civilian objects, in particular cultural property, protection of all those who do not (or no longer) take active part in hostilities, as well as prohibition of means of warfare proscribed in international armed conflicts and ban of certain methods of conducting hostilities. (para. 127)

In the same case, the Tribunal confirmed that customary international law imposes criminal liability for serious violations of Common Article 3, for violations of the other general principles and rules of protection of victims of internal armed conflict, and for breaching certain fundamental principles and rules regarding means and methods of combat in civil strife (para. 134). It stated that violations of Common Article 3 constitute war crimes regardless of whether they occurred within an internal or an international armed conflict (para. 137). Hence, the Tribunal has solved a discussion concerning the legal status of war crimes in non-international armed conflicts and the seeming weakness of the content of Additional Protocol II relating to the punishment of offenses. On the basis of the arguments of the Nuremberg Tribunal, the ICTY stated the possibility of prosecuting authors of such crimes, even in the absence of a formal ratification of Additional Protocol II (paras. 100, 119).

In the Celebici Camp Case , the ICTY Appeal Chamber stated on 20 February 2001 (IT-96-21-A) that “in light of the fact that the majority of the conflicts in the contemporary world are internal, to maintain a distinction between the two legal regimes and their criminal consequences in respect of similarly egregious acts because of the difference in nature of the conflicts would ignore the very purpose of the Geneva Conventions, which is to protect the dignity of the human person” (para. 172).

In the Rutaganda Case (6 December 1999), the ICTR Trial Chamber stated that in case of conflict, international humanitarian law applies in the whole territory and to the whole population. The Chamber pointed to the fact that “the protection afforded to individuals under the Geneva Conventions and the Additional Protocols, extends throughout the territory of the State where the hostilities are occurring . . . are not limited to the ‘front’” or to the “narrow geographical context of the actual theater of combat operations” (paras. 102–3). This verdict was confirmed by the ICTR Trial Chamber in several cases: Akayesu , ICTR-96-4-T, 2 September 1998 (para. 635); Kayishema and Ruzidana , ICTR-95-1-T, 21 May 1999 (paras. 182–83); Musema , ICTR-69-13-A, 27 January 2000 (para. 284); and Semanza , ICTR-97-20-T, 15 May 2003 (para. 367).

📖 For Additional Information:

Abi-Saab, Georges. “Non-international Armed Conflicts.” In International Dimensions of Humanitarian Law , 217–39. Geneva: Henry Dunant Institute, 1998.
Bartels, Rogers. “Timelines, Borderlines and Conflicts: The Historical Evolution of the Legal Divide between International and Non-international Armed Conflicts.” International Review of the Red Cross 873 (2009): 35–67.
Carswell, A. J. “Classifying the Conflict: A Soldier’s Dilemma.” International Review of the Red Cross 873 (2009): 143–61.
Ewumbue-Monono, Churchill. “Respect for International Humanitarian Law by Armed Non-state Actors in Africa.” International Review of the Red Cross 864 (2006): 905–24.
Fujita, Hisakazu. “Application of the International Humanitarian Law to Internal Armed Conflicts.” In A Century of War and Peace: Asia-Pacific Perspectives on the Centenary of the 1899 Hague Peace Conference , edited by Timothy L. H. MacCormack, Michael Tilbury, and Gillian D. Triggs, 139–54. The Hague: Kluwer Law International, 2001.
Gasser, Hans-Peter. “Internationalized Non-international Armed Conflict: Case Studies of Afghanistan, Kampuchea and Lebanon.” American University Law Review 33 (1983): 145–61.
ICRC. “International Humanitarian Law and the Challenges of Modern Armed Conflicts.” Extracts from the Report of the International Committee of Red Cross for the 28th International Conference of the Red Cross and Red Crescent, Geneva, December 2003.
International Institute of Humanitarian Law. “The Manual on the Law of Non-international Armed Conflict.” San Remo, 2006.
Meuthey, Michel. “Non-international Armed Conflicts and Guerrilla Warfare.” In International Criminal Law , edited by M. Cherif Bassiouni, 417–38. Ardsley, NY: Transnational, 1999.
Moir, Lindsay. The Law of Internal Armed Conflict . Cambridge: Cambridge University Press, 2002.
Paulus, A., and M. Vashalmadze. “Asymmetrical War and the Notion of Armed Conflict: A Tentative Conceptualization.” International Review of the Red Cross 873 (2009): 95–125.
Pejic, Jelena. “Status of Armed Conflicts.” In Perspective on the ICRC Study on Customary International Humanitarian Law , edited by E. Wilmshurst and S. Breau S, 77–100. Cambridge: Cambridge University Press, 2007.
Pfanner, T. “Asymmetrical Warfare from the Perspective of Humanitarian Law and Humanitarian Action.” International Review of the Red Cross 857 (2005): 149–74.
“Rules of International Humanitarian Law Governing Conduct of Hostilities in Non-international Armed Conflict: Conclusions of the 14th Round Table at the International Institute of Humanitarian Law in San Remo.” International Review of the Red Cross 278 (September–October 1990): 383–403.
Schabas, William. “Punishment of Non-State Actors in Non-International Armed Conflict.” Fordham International Law Journal 26, no. 4 (2003): 907–33.
Somer, J. “Jungle Justice: Passing Sentence on the Equality of Belligerents in Non-international Armed Conflicts.” International Review of the Red Cross 867 (2007): 655–90.
Stewart, James G. “Towards a Single Definition of Armed Conflict in International Humanitarian Law: A Critique of Internationalized Armed Conflict.” International Review of the Red Cross 850 (2003): 313–50.
Vité, S., “A Typology of Armed Conflicts in International Humanitarian Law: Legal Concepts and Realities.” International Review of the Red Cross 873 (2009): 69–94.

last update: 10 May 2026