Non-State Armed Groups in NIAC: Does IHL Provide Legal Authority for the Establishment of Courts?

The recent Serdar Mohammed v. Ministry of Defencecase has prompted a number of interesting and insightful posts addressing the issue of whether international humanitarian law (IHL) provides a legal basis for detention in Non-International Armed Conflicts (NIAC) (see, for example, here, here, here and here). This discussion offers an opportunity to address the issue of non-State armed groups, something not discussed in detail so far, with the notable exception of Aurel Sari’s post. In particular, the existing debate with regard to detention raises, more broadly, the issue of the legal authority extended to non-State armed groups party to a NIAC. In this post, I present an argument in support of one of the most controversial issues in this area: the authority of armed groups to establish courts.

Does IHL regulate armed group courts?

As is well known, IHL does not provide an explicit basis for the establishment of courts in NIAC, but rather regulates their operation in the event they are in fact established. In this regard IHL contains two relevant rules. Common Article 3(1)(d) of the Geneva Conventions of 1949 prohibits ‘the passing of sentences and the carrying out of executions without previous judgment pronounced by a regularly constituted court’, while Article 6 of Additional Protocol II (AP II) requires that ‘[n]o sentences shall be passed and no penalty shall be executed on a person found guilty of an offence except pursuant to a conviction pronounced by a court offering the essential guarantees of independence and impartiality’. Regarding the common Article 3 requirement that a court be ‘regularly constituted’, sources such as the ICRC Customary IHL Study note that a court may satisfy this requirement ‘if it has been established and organized in accordance with the laws and procedures already in force in a country.’ This would appear to support the argument that IHL does not provide a specific legal basis for the establishment of courts (authority is derived from the municipal law in force). At the same time, this reasoning also appears to preclude the convening of armed group courts since domestic law is (almost certainly) unlikely to establish a legal basis for non-State armed group courts. That said, it should be noted that the Pictet Commentary to the Geneva Conventions does not equate the regularly constituted requirement with a basis in municipal law, but rather focuses on the prohibition of ‘summary justice’.

Article 6(2) AP II – which ‘develops and supplements’ common Article 3 – dispenses with the ‘regularly constituted court’ provision, requiring instead that a court offer ‘the essential guarantees of independence and impartiality.’ The ICRC Commentary notes that this was a deliberate act during drafting, as ‘some experts argued that it was unlikely that a court could be “regularly constituted” under national law by an insurgent party’. Indeed, with respect to Articles 6(2)(c) and (d) Additional Protocol II, Sivakumaran notes that ‘the phrase ‘national law’ was omitted from the final text […] precisely because of the uncertainty over whether the term was wide enough to cover the ‘law’ of the armed group’. Reinforcing this conclusion is the fact that, referring to Article 6(2)(c) AP II, the UK Manual of the Law of Armed Conflict considers that ‘the use of the bare word “law” must be taken to include both national and international law. It could also be wide enough to cover “laws” passed by an insurgent authority’ (p. 404, footnote 94).

The apparently deliberate extension of international regulation to non-State armed groups is underlined by the fact that Article 75(4) of AP I – which was drafted at the same time as AP II to regulate international armed conflict and so primarily addresses State obligations – maintains the pre-existing language of common Article 3, referring to ‘a regularly constituted court’. Presuming that this different language was deliberate, there is reason to believe that the drafters did intend to regulate courts convened by armed groups in AP II conflicts, and a plain text reading unequivocally indicates that this was also the case with respect to common Article 3 (i.e. ‘each Party to the conflict shall be bound’); this conclusion is supported by the fact that AP II ‘develops and supplements’ common Article 3.

How should the intention to regulate armed group courts be interpreted?

In light of this intention, we cannot conclude that IHL does not provide a legal basis for the convening of courts, or requires that armed group courts be established on the basis of domestic law (effectively an impossibility). By developing international treaty law to regulate the operation of armed group courts, while considering all such courts to be illegal, States would have undertaken an exercise in futility. To interpret a treaty in this manner is inconsistent with the international law of treaty interpretation, and in particular the ut res magis valeat quam pereat principle, which holds that ‘a treaty must be given an interpretation that enables its provisions to be ‘effective and useful’’ (see Cassese, International Law, p. 179).  Of course, it is noted that IHL does regulate certain illegal situations (i.e., the jus in bello applies irrespective of whether there has been a violation of the jus ad bellum). However, this regulation is distinguished from that of armed group courts. If IHL does not establish a legal basis for armed group courts then all such courts are prohibited, and law would have been created to regulate inherently illegitimate activity. This is not the case with respect to the use of force: the use of force is not inherently illegal, and may be legitimate in cases of self-defence, or consequent to a Security Council authorisation, for example. By regulating armed conflict, international law is not seeking to regulate an inherently unlawful situation.

On this basis, and in accordance with the principle that more recent law prevails over an inconsistent earlier law principle (lex posterior derogat priori), it can be concluded that the law of NIAC provides a legal basis for the convening of courts by non-State armed groups. By regulating the operation of armed group courts, States implicitly (but necessarily) established the authority to convene such courts. This understanding appears fully consistent with the desire to prohibit summary justice, and it is pertinent to note that although article 8(2)(c)(iv) of the Statute of the International Criminal Court echoes the language of common Article 3(1)(d) and refers to ‘a regularly constituted court’, the Elements of Crimes interprets this provision in a manner similar to that established in AP II: i.e. as referring to the requirements of independence and impartiality, without mentioning any basis in national law.

Having argued that IHL provides legal authority for non-State armed groups to establish courts in NIAC, I will now finish with a caveat. Although legal authority exists, this does not mean that in practice all armed groups can convene courts: numerous other factors must be satisfied, many of which will be beyond the reach of armed groups. For example, any court established by an armed group must be independent and impartial, and must satisfy numerous fair trial guarantees. Of particular interest is satisfaction of the nullen crimen sine lege requirement established in Article 15 of the International Covenant on Civil and Political Rights. What crimes can the courts of non-State armed groups prosecute: are these to be derived from international law, municipal law, or the law of the armed group?