The central focus of this post is on the Secretary of State’s proposition that authority to detain in a NIAC can be derived from IHL treaty law. Relying on Common Article 3 and Articles 5 and 6 of Protocol II, the Secretary of State argued that these provisions imply an authority to detain in NIACs. Support was taken from Gill’s and Fleck’s proposal (see para 240) that although IHL treaty law concerning NIACs is less explicit in stipulating the legal basis for operational detention than IHL treaty law concerning IACs:
“…a generic power to that effect is implicit in Common Article 3, in as much as it identifies as one category of persons taking no active part in hostilities ‘those placed hors de combat by… detention’. Articles 5 and 6 of (Protocol II) also refer to ‘persons deprived of their liberty for reasons related to the armed conflict, whether they are interned or detained’, which makes it clear that the deprivation of physical liberty of a person is contemplated in the law applicable to non-international armed conflicts.”
This approach forms the basis of the ICRC’s assertion that Common line database Article 3 and Protocol II govern deprivation of liberty in NIAC (page 6). Because Protocol II – which relates exclusively to NIACs – explicitly mentions internment, the ICRC expresses the view that this confirms that internment “is a form of deprivation of liberty inherent to NIAC” (page 7).
The Court of Appeal nevertheless concluded that “it is not possible to base any implication of a power to detain in an internationalised non-international armed conflict purely on a treaty” (para 219). The Court of Appeal most certainly got it right, for various reasons.
If the Geneva Conventions and their Additional Protocols had intended to provide a power to detain in a NIAC, this would have been expressly provided
Normal principles of interpretation require that, where certain matters have been explicitly set out in a legal instrument, the lack of similar explicit reference elsewhere in the legal instrument calls for interpretation that such matters are excluded (the principle of expressio unius). It is therefore relevant to contrast the way in which the authority to detain is dealt with in the context of international versus non-international armed conflicts.
The authority to detain in an IAC is set out in great detail within IHL treaty law. Specific authorisation and substantive grounds are specified in Article 21 of Geneva Convention III (concerning POWs) and Articles 42 and 78 of Geneva Convention IV (concerning civilians posing a serious threat to security). In contrast, the Geneva Conventions and their Additional Protocols are silent concerning grounds or procedures for internment in the context of a NIAC.