Detainee Transfers and the Principle of Non-refoulement in Relation to ‘Non-belligerent Supporting States’ in Non-international Armed Conflicts

Abstract In the past 20 years, many States have purposefully shifted away from taking detainees in non-international armed conflicts (NIACs) and have instead relied on partner forces—both State and non-State actors—to take responsibility for any NIAC detainees. The question this article seeks to address is to what extent ‘non-belligerent supporting States’ have obligations to ensure that detainee transfers by partners comport with the principle of non-refoulement, by which a person may not be transferred if they are at a real (or substantial) risk of a violation of their fundamental rights. The authors explore several legal approaches to better understand how a non-belligerent supporting State may incur legal obligations in relation to detainee transfers through the support it provides. The article first examines how support triggers belligerent status (and thus belligerent obligations) under International Humanitarian Law (IHL), and tackles to what extent non-belligerent supporting States may incur legal obligations under IHL more generally, noting the gap between the rules of International Armed Conflict and NIACs in this respect. Secondly, specific obligations non-belligerent States may incur with respect to the principle of non-refoulement in relation to detainee transfers by a belligerent party during a NIAC are identified. Finally, the authors examine three categories of support—logistics/transportation support, intelligence sharing, and belligerent-party-to-non-belligerent-party detainee transfers—to demonstrate how varying degrees of support by non-belligerent States in the context of a NIAC could trigger the obligations to ensure respect of the prohibition against non-refoulement by belligerent partners through the auspices of Common Article 1. The article concludes that while Common Article 1 obligations indeed arise in these scenarios, the scope of the external or positive obligations of Common Article 1 are still unsettled under IHL and thus require further development to create a common understanding of the international legal obligations to avoid the violation of the principle of non-refoulement by partner forces.