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The Syrian Detention Conundrum: International and Comparative Legal Complexities

By Dan E. Stigall, U.S. Department of Justice. Published at Harvard National Security Journal, Vol 11, Issue 1, 54-105, 2020.

Streets of Syria, by Aladdin Hamammi.


The phenomenon of battlefield detention by non-state groups is increasingly common and has been recently brought into focus by events in Syria where, as part of the international effort to counter the Islamic State of Iraq and Syria (“ISIS”), the United States and coalition partners have worked “by, with, and through” a non-state armed group called the Syrian Democratic Forces (“SDF”). That successful partnership has resulted in significant battlefield victories — and the resultant detention by SDF of more than 2,000 ISIS foreign fighters. A detention conundrum has, however, been created by the modern reliance by states on non-state actors for counterterrorism operations, and their simultaneous reluctance to accept the return of terrorists captured and detained by non-state actors in the course of those operations. Specifically, SDF partners have signaled that they do not have the capacity or authority for the continued detention of the foreign terrorist fighters captured in the course of the successful counter-ISIS effort. Moreover, the countries of origin of these captured terrorists are reluctant to accept their return, citing to legal obstacles to repatriation. The inability of non-state partners to detain foreign fighters indefinitely, coupled with the refusal of countries to repatriate their nationals, risks the release of dangerous terrorists. To assist in navigating this complex situation, this Article illuminates the international and comparative legal issues associated with the detention of terrorists by non-state armed groups and clarifies the legal issues relating to the repatriation of detained foreign terrorist fighters by the SDF in Syria. Through this analysis, the Article ultimately demonstrates that international law and the domestic law of many international partners generally permits the lawful transfer of foreign fighters from the custody of a non-state entity to government authorities for prosecution, rehabilitation, or other appropriate means of preventing their return to terrorism.

Keywords: Syria, Syrian Democratic Forces, ISIS, detainees, detained, non-state armed groups, nonstate armed groups, repatriation, abuse of process.

I. Introduction

In October 2019, almost immediately after the decision to withdraw U.S. military forces from northern Syria, the Turkish military began an offensive against the Kurdish non-state actors that had previously been allied with the United States for years in a relatively successful counterterrorism effort.(1) The manifold impacts of this decision were immediately apparent. Along with the concerns relating to potential war crimes being perpetrated against Kurds,(2) attention quickly turned to the negative effect this decision might have in permitting a resurgence of terrorist groups in Syria.(3) A specific concern was the potential battlefield release of large numbers of foreign terrorist fighters that had been detained by Kurdish non-state forces in Syria, and which the Kurdish forces might no longer be able to effectively guard once the Turkish offensive began.(4) Indeed, within days of the commencement of the Turkish offensive, a small number of detained foreign terrorist fighters began to escape,(5) along with greater numbers of terrorist-affiliated women and their children who had been confined to camps for internally displaced persons.(6) At the time of the writing of this Article, Syrian regime forces and Russian troops have moved into areas where U.S. forces were previously positioned.(7) While the dynamics of the battlefield do not lend themselves to easy prognostication, and though the situation now seems to have stabilized to some degree, one may assess that the release and escape of more detained terrorists and their adherents remains possible.

Observers of Syria and the international counterterrorism effort may well question how much of this situation was avoidable. Why were there so many terrorists detained in Syria by non-state actors in such precarious circumstances? Why were those terrorists not previously returned to their home countries for prosecution? While the answers to such questions are irreducibly political and relate, in part, to policy choices made by the governments of the detained terrorists’ countries of origin, the answers also implicate important questions of international and comparative law that govern the legal permissibility of the repatriation and subsequent prosecution of terrorists who are captured and detained by non-state armed groups.

A. Non-State Actors and the Syrian Battlefield

Non-state actors are an increasingly central part of the global security landscape.(8) This is due to a variety of factors, including the effects of globalization, which “have transformed the process of technological innovation while lowering entry barriers for a wider range of actors to develop and acquire advanced technologies.”(9) As early as 2010, the U.S. Department of Defense Quadrennial Defense Review anticipated that “[a]s technological innovation and global information flows accelerate, non-state actors will continue to gain influence and capabilities that, during the previous century, remained largely the purview of states.”(10) Likewise, over a decade ago, Efraim Halevy, a former Mossad chief and National Security Advisor to the Prime Minister of Israel, noted that non-state actors are increasingly emerging as key players in the geopolitical arena, that they will be increasingly varied, and that they will test the abilities of sovereigns to respond to the challenges they pose.(11) The relationship between states and non-state actors, however, is not always adversarial. In fact, states increasingly rely on nonstate armed groups “to supplement regular armed forces.”(12)

An example of a partially advantageous state/non-state relationship can be witnessed in the recent international effort to counter the Islamic State of Iraq and Syria (“ISIS”) in Syria,(13) which featured a particularly advantageous partnership between an international coalition of seventy-four nation states (the Global Coalition to Defeat ISIS)(14) and a non-state alliance of mainly Kurdish, Arab, Syriac Christian, and Turkmen fighters in Syria called the Syrian Democratic Forces (“SDF”).(15) The SDF, which was assembled with the assistance and support of the United States in late 2015,(16) has varied in size and composition since its inception, but generally consists of approximately 60,000 fighters from diverse origins.(17) Working “by, with, and through”(18) this “local, indigenous partner ground combat force,”(19) the Global Coalition to Defeat ISIS has repeatedly prevailed against ISIS on the battlefield and, in early 2019, successfully liberated the physical caliphate that ISIS once controlled.(20) The partnership with the SDF also facilitated the successful military operations which eliminated senior ISIS leadership, most notably Abu Bakr al-Baghdadi.(21)

Suggested Citation:

Stigall, Dan E., The Syrian Detention Conundrum: International and Comparative Legal Complexities (January 8, 2020). Harvard National Security Journal, Vol 11, Issue 1, 54-105, 2020 .


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