The detainment and prosecution of ISIS-fighters has gained attention in the post-caliphate era in Syria and Iraq. The flow of foreign fighters from Western countries during the peak of ISIS has made this issue more problematic by adding a complex international dimension to it. The reluctance of Western countries to repatriate their citizens has placed foreign ISIS-fighters in a situation of constant uncertainty. This also mirrors millions of civilians who suffered from the reign of ISIS and the crimes committed by its members. Furthermore, the situation has potentially devastating consequences for the generation emerging from the former rule of ISIS and rampaging civil war in Syria. The legal limbo of both ISIS-fighters as well as civilians, presents an opportunity for radicalization to flourish. Since it is not clear on whom the responsibility for ISIS-fighters falls, courts by non-state armed groups (NSAGs) have emerged to fill this vacuum.

What are then, the possible solutions and problems that courts by NSAGs raise in the prosecution of ISIS-fighters? According to international human rights standards, Syrian and Iraqi courts do not meet the conditions to prosecute ISIS-fighters. Courts by NSAGs then, present an opportunity to tackle the problems of ISIS-fighters stuck in a legal uncertainty and civilians waiting for justice. However, there are issues of pertaining to the rule of law as well as, social accountability. One empirical example of courts by NSAGs is the Autonomous Administration of North and East Syria (AANES) which has taken the task to prosecute local ISIS-fighters, but not foreign fighters. AANES is led by the Syrian Democratic Forces which consists mostly of Kurdish militants. I will now offer a brief consideration on the issue of courts by NSAGs from a socio-legal perspective.

A solution?
Whilst courts by NSAGs are prohibited under a state’s domestic law, they are in principle, allowed under the international humanitarian law. This offers room for NSAGs to fill gaps of judicial and societal responsibility in situations of limited statehood. At the moment, it is not clear who is responsible for the prosecution of ISIS-fighters and for example, an international tribunal seems unlikely. Courts by NSAGs can bring justice for victims of ISIS, which is essential in the reconstruction and consolidation of civilian grievances. Furthermore, it links to a broader, lingering security threat of (re-)radicalization of ISIS-fighters in prisons in Syria and Iraq. By prosecuting ISIS-fighters in courts by NSAGs, civilians are also heard which is important in a working society and justice. For example, AANES has gained more social legitimacy for its rulings in Syria than the official Syrian courts. Nevertheless, courts by NSAGs seem to remain a short-term solution and are hindered by gaps of transparency, rule of law and legal certainty.

A problem?
Courts by NSAGs seem to raise more problems than solutions. Since these courts usually operate within situations of limited statehood, they erode the legitimacy and sovereignty of the state. In the case of AANES, Syria is an internationally recognized state whereas the Kurdish administration is not. This poses issues internationally as well as, locally. International actors, including sovereign states and supranational institutions such as the European Union, have rules in place regarding the respect of the sovereignty of other states. Offering legal and social assistance for NSAGs in their efforts to prosecute ISIS-fighters fairly can be interpreted as a sign of recognition which might lead to political disputes between states. Locally, courts by NSAGs might cause problems of social legitimacy because their forms of governance and relationships with the civilian population vary. The Kurdish administration has aimed to refrain from the use of indiscriminate violence and brutal force in Syria. On the other hand, ISIS exercised brutal authority and coercion during their periods of governance in Syria and Iraq. This problematizes courts by NSAGs since there are major differences in how NSAGs use law and courts and the relationship they have with the civilian population.

Concluding remarks
The prosecution of foreign and local ISIS-fighters is puzzling at a state level as well as, the individual level. It lies in the crossroads of law and society as it relates to issues of radicalization, social legitimacy, and international security. It seems that the current framework of international humanitarian law is not equipped to address the problem. Instead, courts by NSAGs have emerged to prosecute ISIS-fighters in this legal vacuum. Courts by NSAGs can be a tool to bring justice to the victims of ISIS and civilians as well as, address the problem of legal uncertainty of ISIS-fighters stuck in Kurdish prisons. This is important for the post-conflict reconstruction and consolidation of grievances among the civilian population. However, courts by NSAGs seem to pose more problems than solutions within the current legal framework. State sovereignty is problematic as NSAGs are not recognized states and this, therefore, limits the options of social and legal assistance by other states. Moreover, the nature of NSAGs and their relationship with civilians varies to a great extent, which causes problems of social legitimacy and accountability. Empirically, NSAGs have demonstrated also advantages in post-conflict reconciliation but remain limited regarding the legal framework. Consequently, we should critically assess current legal frameworks and practices when it comes to the prosecuting ISIS-fighters and the role of NSAGs.

References
Berti, B. (2021). “Rebel justice? Rule of law and law enforcement by non-state armed groups”. In: Hamid, L. and Wouters, J. (eds). Rule of Law and Areas of Limited Statehood: Domestic and International Dimensions, 119-136. Edward Edgar Publishing Limited.
Mehra, T. and Wentworth, M. (2021). “New Kid on the Block: prosecution of ISIS fighters by the Autonomous Administration of North and East Syria”, https://icct.nl/publication/prosecution-of-isis-fighters-by-autonomous-administration-of-north-east-syria/, Consulted on March 31st, 2021.
Mehra, T. and Paulussen, C. (2019). “The Repatriation of Foreign Fighters and Their Families: Options, Obligations, Morality and Long-Term Thinking”, https://icct.nl/publication/the-repatriation-of-foreign-fighters-and-their-families-options-obligations-morality-and-long-term-thinking/, Consulted on March 31st, 2021.
Willms, J. (2012). “Justice through Armed Groups’ Governance – An Oxymoron?”, SFB-Governance Working Paper Series, 40: 1-32.

Jasmin is a member of the Conflict Security and Crime SRC. She is currently completing her MSc in International Relations at the University of Amsterdam. Her interests include the interplay between ideology and armed groups. Additionally, she is interested in the role of terrorist organizations in conflict areas and the implications for post-conflict situations.