The capture of a senior ISIS leader in Aleppo, Syria yesterday is welcome news. In a brief statement, Combined Joint Task Force – Operation Inherent Resolve (CJTF-OIR) confirmed that coalition forces apprehended a man subsequently identified as Hani Ahmed al-Kurdi, described as an experienced bomb maker responsible for facilitating attacks on U.S. and partner forces. His capture will likely not only remove a top operational threat but could provide U.S. and coalition partners the ability to interrogate him and potentially learn more about ISIS plotting. Moreover, the operation appears to have achieved its aim without incurring any coalition or civilian casualties—a significant achievement in light of growing criticism of U.S. military operations following a series of revelations on civilian harm. Nevertheless, it raises a host of potential issues concerning the detention and prosecution of terrorists in areas where the United States does not have a large presence on the ground, an issue that may be increasingly important as U.S. forces draw down from previous operational levels in Iraq and Syria.

 Coalition forces have not yet disclosed sufficient information on al-Kurdi’s detention to provide a clear picture of what comes next. We do not know key facts such as al-Kurdi’s citizenship, nor has the Department of Defense indicated where he is being held, by whom, or whether any criminal charges could be brought in the United States or other jurisdictions. Each of these details will be key to his own future disposition, and depending on the answers, could also provide a roadmap for future high-level ISIS captures (assuming, as seems to be the case, the United States remains engaged in these types of operations for the foreseeable future).

But none of the options for al-Kurdi’s future disposition are straightforward – his capture raises persistent thorny questions about how high-level terrorists are detained. These questions are particularly important to answer as the United States enters a new, lower intensity, yet seemingly persistent fight against terrorist groups. 

Based on previous cases, the administration is likely considering three potential dispositions for al-Kurdi: detention by Syrian Democratic Forces (SDF) inside Syria, detention by a regional partner, or prosecution by the United States or a close ally (law of war detention by the United States in Syria or in U.S. territory are likely off the table, as we explain below). 

First, given the location of his capture, it’s likely that the SDF played a role in the operation, and even now he could well be held in a prison administered by the group. Although they have successfully detained some ISIS members, most notably the so-called ISIS Beatles reponsible for murdering American hostages in Syria, long-term detention by the SDF still presents security concerns, since the SDF’s overall track record of securing ISIS prisoners is mixed. Most recently, the Jan. 20 ISIS attack on an SDF prison in al-Hasakah, Syria—which lasted ten days, resulted in over 500 casualties, and led to the escape of potentially hundreds of ISIS prisoners—highlights the challenges SDF partners face as a non-state actor subject to attack by nation-state forces and ISIS remnants alike and lacking the diplomatic, intelligence, and defense capabilities of a state. For these same reasons, the SDF continues to struggle with the difficult task of figuring out what to do with the estimated 43,000 men, women, and children who were once associated with ISIS and continue to be held in camps throughout Syria and Iraq (where conditions are horrendous). Adding high-level ISIS detainees to SDF facilities inside Syria won’t help the situation, but may be the default option.

The second disposition pathway would be for coalition forces to turn to a third country for help, an option that would be particularly viable if al-Kurdi is a foreign fighter operating in Syria or if he is responsible for the deaths of citizens of a third country. If al-Kurdi is Iraqi or if he is demonstrably linked to attacks on Iraqi targets, for example, he could be transferred to the custody of the Iraqi government or potentially the Kurdistan Regional Government for detention or prosecution. The same rationale would apply in transferring him to the custody of another regional or coalition partner. 

The viability of a third country transfer, however, ultimately depends on al-Kurdi’s citizenship, his specific acts, and the reliability of partners under consideration in terms of their ability to hold fair trials if prosecution is contemplated, their ability to securely hold ISIS detainees, and their track record on humane treatment of detainees (assuming the United States holds al-Kurdi and/or would be assisting in his transfer to a third country, U.S. non-refoulement obligations would apply). This last concern is not trivial, given how many U.S. counterterrorism partners have a history of obtaining information from detainees through torture. And even on the security side, while U.S. military and intelligence have a long history of counterterrorism cooperation with many regional partners, others have proven less reliable in securing, let alone successfully prosecuting, detainees. 

Finally, al-Kurdi could be transferred to the United States to face criminal charges, such as providing material support for terrorism or charges related to specific crimes he may have committed as an ISIS leader. Nearly 700 foreign terrorists have been prosecuted and convicted in U.S. federal courts since 9/11, including a number of ISIS fighters and supporters since the U.S. became involved in that conflict in 2014 (mostly American foreign fighters). However, unless al-Kurdi is a U.S. national (or has committed crimes against U.S. persons for which evidence sufficient to convict in a criminal trial is available), transferring him for prosecution to the United States is an unlikely path.

In previous years, al-Kurdi might have been considered for long-term law of war detention by the United States. But the United States has avoided holding ISIS detainees in exclusive U.S. custody for several reasons: out of respect for local partners, due to the lack of an appropriate long-term detention facility in a country where the U.S. presence is small and on shaky legal ground, and partly to avoid facing any situation that could lead to a habeas petition challenging the application of the 2001 Authorization for Use of Military Force (AUMF) to ISIS. Bringing al-Kurdi to a military facility in the United States, or to Guantanamo (which will be rightly off the table in the Biden administration), would open the door to such a challenge. The United States avoided a ruling on the merits of this issue in Doe v. Mattis, a habeas case brought by a U.S.-Saudi dual national ISIS detainee captured in Syria, which ended after over a year of law-of-war detention in Iraq with a transfer to Bahrain and a canceled U.S. passport.  Losing on the merits of a habeas case brought by an ISIS detainee could undermine a range of the government’s claimed war powers under the 2001 AUMF—a risk the United States would surely go to great lengths to avoid. 

Ultimately, we applaud the U.S. decision to capture al-Kurdi rather than kill him, and the successful conclusion of the operation without harm to civilians or coalition forces, even while we recognize the difficulties that a case like his presents. Identifying an appropriate long-term disposition will likely prove difficult in al-Kurdi’s case, but is essential for future capture operations, both in Syria and beyond.

Image: BAGHOUZ, SYRIA – MARCH 24, 2019: A Syrian Democratic Forces (SDF) fighter walks past destroyed vehicles in the final ISIL encampment on March 24, 2019 in Baghouz, Syria. The Kurdish-led and American-backed Syrian Defense Forces (SDF) declared on March 23 the “100 percent territorial defeat” of the so-called Islamic State, also known as ISIS or ISIL. The group once controlled vast areas across Syria and Iraq, a population of up to 12 million, and a “caliphate” that drew tens of thousands of foreign nationals to join its ranks. (Photo by Chris McGrath/Getty Images)