From Nigeria to Russia, the number of entities claiming affiliation with the Islamic State Group (ISG) is on the rise. In Colombia, concerns arise over the possible splintering of the main armed groups into hostile factions, which might endanger the ongoing peace process. Delineating the conceptual boundaries of organized armed groups – i.e. determining whether a splinter faction is a separate entity from its parent group, or whether an armed faction is part of the group to which it professes allegiance – is critical for the applicability of international humanitarian law (IHL). As Ellen Nohle argues, a faction can be considered a separate entity if it does not or no longer ‘belong’ to the original armed group. This will be the case when it is not, or no longer, under its ‘command and direction’.

What are the conceptual boundaries of organized armed groups for the purpose of IHL applicability? This question, inextricably bound to one’s understanding of the notion ‘organized armed group’, is gaining a sense of urgency with the perceived spread of ISG. The latter has announced affiliates in different parts of the world, including West Africa, Libya and the Khorasan region – while many more armed factions have pledged allegiance to the group. States that might already be in armed conflict with ISG have engaged or contemplate engaging in hostilities with announced or self-declared ISG affiliates. While this raises an array of complex legal issues, including the territorial scope of IHL, it also brings to the fore the more basic question of how to delineate armed groups for the purpose of classifying non-international armed conflicts (NIACs) and applying IHL.

This issue is also germane to peace processes. In an article on the Colombian peace process, the authors noted that while the risk of a splinter faction of the Revolutionary Armed Forces of Colombia (FARC) continuing to engage in hostilities following a peace agreement might be low, the risk cannot be discounted and might endanger the peace process. This raises the question of whether continued armed violence by a splinter faction necessarily prevents concluding that there has been “a lasting cessation of armed confrontations without real risk of resumption” between the original parties, i.e. that the NIAC has ended. (See ICRC’s updated Commentary on Article 3, at 491. Contrast with M. Milanovic, who argues that a NIAC may end once the level of intensity required for its existence is no longer met.)

If the splinter faction is still part of the parent group, armed confrontations between that faction and the other party to the NIAC might preclude the NIAC from ending, despite an apparent commitment to peace by the parent group (i.e. because there has not been a cessation of armed confrontations). If, on the other hand, the splinter faction is a separate entity from the parent group, armed confrontations between that entity and the other party to the NIAC will not prevent the NIAC from ending (i.e. since it does not impact the assessment of whether there has been a cessation of armed confrontations between the original parties). Whether or not there will be a new NIAC involving the splinter group is a separate question, requiring consideration of its level of organization and the intensity of hostilities.

Delineating armed groups: ‘belonging’ and ‘command and direction’

Identifying the conceptual boundaries of armed groups is accordingly relevant both in the context of an armed faction claiming to be part of an armed group that is already engaged in a NIAC (possibly raising the issue of the territorial scope of IHL), and in determining at what point a faction that continues to engage in hostilities is no longer part of the original armed group, which is on the road to peace (raising the issue of declassification of a NIAC and possibly classifying a new one).

The test for inclusion in, and disengagement from, an armed group is thus at the heart of delineating armed groups and determining IHL applicability. With respect to inclusion, one approach is to ask whether the aspiring faction ‘belongs to’ the aspired group, by way of analogy to the use of this notion to determine whether an irregular militia is part of a State’s armed forces. Since this notion is already employed in IHL to describe a relationship with a non-state actor (albeit in the context of international armed conflicts), there should be no conceptual difficulty in applying it to determine the relationship between non-state entities (for example, see this post by Ryan Goodman. Contrast with the notion of ‘co-belligerency’ as a description of the relationship between entities. In IHL, this term is associated with the concept of neutrality, which is a legal status of States, thus making the extrapolation of co-belligerency to non-state entities controversial. See this post by K.J. Heller).

While the test for determining a relationship of ‘belonging’ is contested, for the purpose of this post it is considered that an aspiring faction belongs to an armed group if it falls under the ‘command and direction’ of that group. The test expresses the idea that the faction should consider itself bound by the commands issued by the leadership of the armed group, and the armed group should consider failure by the faction to comply with its direction as a breach liable to disciplinary action. This presupposes a structural relationship between the faction and the armed group, and indicative factors include whether the faction falls under the hierarchical structure, chain of command and disciplinary system of the armed group. Based on this, it would not suffice that a faction follows the publicly proclaimed wishes of an armed group, if the armed group’s leadership has not imposed these wishes on the faction by an exercise of decision-making power and the faction recognizes these as directives as opposed to mere wishes.

Where the armed group is party to a NIAC and the aspiring faction operates in a different territory, it is a separate question – pertaining to the territorial scope of IHL – whether the aspiring faction ‘belonging to’ the armed group will become party to the same NIAC or whether there might be a separate NIAC.

Disengagement of a splinter faction from the parent group

As for disengagement from the parent group, two approaches can be considered. The first looks at individual membership and asks whether the members of the splinter faction have disengaged from the original group. Membership in the armed wing of an organized armed group ends when the person ceases to assume a continuous combat function. According to the ICRC’s Interpretive guidance on the notion of direct participation in hostilities, this “need not be openly declared; it can also be expressed through conclusive behavior”.

However, it might not always be clear whether all members of a splinter faction have individually disengaged from the parent group. The second (collective) approach therefore looks at the splinter faction as such and queries whether it constitutes a separate entity. If it does, then assumption of a function in that separate entity might moreover provide evidence of individual disengagement from the parent group, if the new function is in conflict with continued membership in the armed wing of the original group (for instance, where the two groups oppose one another).

To determine whether a splinter faction is a separate entity from its parent group based on the second approach, I would suggest that the test is essentially the same as for determining whether a faction ‘belongs to’ an armed group. That is, a splinter faction can be considered a separate entity when it is no longer under the command and direction of the original group. This can be demonstrated by the fact that the splinter faction no longer falls under the hierarchical structure and chain of command of the parent group. Because of the evidentiary difficulties of assessing the exact moment this occurs, official ‘founding declarations’ by the splinter group might become an important indicative factor (see the International Criminal Court, Prosecutor v Abu Garda). If the splinter faction is separate from the original group, it is another question whether it is also an organized armed group for the purpose of IHL, such that it can be party to a NIAC in its own right.


Conceptualizing the outer limits of armed groups is a fundamental step in assessing the applicability of IHL to armed clashes involving non-state actors. It is not, however, conclusive as to how IHL will apply. For instance, even if an armed faction is considered part of an armed group party to a NIAC in another State, this does not necessarily imply that the armed faction is party to the same NIAC. How IHL will apply, including its territorial scope, is a separate issue and fear of “borderless” or “global” armed conflicts should not impede the quest for greater clarity regarding the conceptual boundaries of armed groups.


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