Does the AUMF Cover ISIS?: Addressing the Merits of Doe v. Mattis

By: Carly Nuttall

In September 2017, a dual United States and Saudi Arabian citizen (“John Doe”) was captured in Syria by the U.S.-allied Syrian Democratic Forces and turned over to U.S. military custody.[1] Since then, Doe has been detained in Iraq under the allegation that he is an ISIS fighter and therefore an unlawful enemy combatant.[2] Although the American Civil Liberties Union (ACLU) filed a habeas petition on Doe’s behalf on October 5, Doe did not have access to legal counsel until late December, when D.C. District Court Judge Tanya Chutkan ordered the U.S. government to provide ACLU lawyers with “immediate, unmonitored” access to Doe.[3] After this meeting, the ACLU reported to the court that Doe both wanted to proceed with his habeas petition and that he wanted the ACLU to serve as his counsel.

Beyond the constitutional questions about access to counsel, this case (Doe v. Mattis), raises an additional important question—does ISIS fall within the Authorization for the Use of Military Force (AUMF)? The AUMF, signed into law by President George W. Bush exactly one week following the September 11th attacks, authorizes the use of the U.S. military against those responsible for the attacks.[4]  Almost immediately upon passage of the AUMF, U.S. forces began taking military prisoners as part of their operations. This practice was upheld by the Supreme Court in Hamdi v. Rumsfeld, in which a U.S. citizen was detained by the U.S. military under the authority of the AUMF.[5]  However, Doe differs from Hamdi in at least one important way. Yaser Hamdi, a U.S. citizen born in Louisiana, was detained by the U.S. military because he was fighting with the Taliban against the United States.[6]  The AUMF specifically allows the President to use “[a]ll necessary and appropriate force against those nations, organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons….”[7]   The Taliban clearly falls within these categories.

Much less certain, however, is whether Doe’s alleged affiliation with ISIS also falls within the AUMF’s authority. ISIS itself was not in existence at the time of the September 11th attacks, which would seem to preclude the U.S. military from detaining Doe. However, over time, the AUMF has been interpreted to extend to “associated forces” of “nations, organizations, or persons” in existence at the time of the September 11th attacks. In March 2009, the U.S. Department of Justice submitted a memorandum to the United States District Court for the District of Columbia in In re: Guantanamo Bay Detainee Litigation.[8]  In this memorandum, the U.S. government asserted that the AUMF also granted the President “the authority to detain persons who were part of, or substantially supported, Taliban or al-Qaida forces or associated forces that are engaged in hostilities against the United States or its coalition partners, including any person who has committed a belligerent act, or has directly supported hostilities, in aid of such enemy armed forces.”[9]  This interpreted expansion of the AUMF’s authority was subsequently adopted by the United States Court of Appeals for the District of Columbia Circuit.[10]  This expanded view was reaffirmed in the National Defense Authorization Act for Fiscal Year 2012 when Congress reiterated the authority to detain “[a] person who was a part of or substantially supported al-Qaeda, the Taliban, or associated forces that are engaged in hostilities against the United States or its coalition partners, including any person who has committed a belligerent act or has directly supported such hostilities in aid of such enemy forces.”[11]  Though this was a dramatic expansion of the AUMF’s original terms, within two years it had been adopted by the executive, judicial, and legislative branches. This interpretation of the AUMF remains the current applicable framework.

Doe v. Mattis presents the opportunity to determine whether ISIS falls within this “associated forces” category. Although this question has existed in academic and policy circles for some time, official judicial review of the issue requires a detention of this type, and no ISIS-affiliated detainee has been able to bring a habeas petition until now. On the one hand, ISIS certainly did not exist in 2001 and it broke away from al-Qaida several years ago over a disagreement regarding control of Al-Qaida’s al Nusrah affiliate in Syria.[12]  This would seem to clearly support that ISIS is not covered by the AUMF. However, on the other hand, ISIS was previously known as al-Qaida in Iraq, which was very clearly within the authority of the 2001 AUMF. Congress has also been funding large-scale combat operations against ISIS for years with the understanding that ISIS is within the scope of the AUMF. Given these latter two considerations, it seems unlikely that courts would determine that ISIS does not fall within the auspices of the AUMF.

But the analysis does not end there. Because John Doe is a U.S. citizen, he also falls within the scope of the 1971 Non-Detention Act. The Non-Detention Act states that U.S. citizens cannot be detained except pursuant to an Act of Congress.[13]  There is some uncertainty about whether the AUMF is sufficiently clear in its language to satisfy the Non-Detention Act, as the AUMF does not specifically refer to detention of citizens. The Hamdi case sheds some light on where the court will focus its opinion. As part of its holding, the Supreme Court accepted the government’s argument that the AUMF could be construed as sufficient to overcome a Non-Detention Act challenge, but only if conventional armed conflict (or something like it) continued to exist in Afghanistan.[14]  Although the conflict in Syria and Iraq is constantly changing, the court will likely find that combat operations there continue to fall under the mantle of conventional armed conflict, further bolstering the government’s argument in favor of detention. As a point of comparison, the drug wars in Mexico are often used as an example of unconventional armed conflict.

Under the expanded interpretation of the AUMF to include “associated forces” and the presence of conventional armed conflict satisfying the Non-Detention Act requirement discussed in Hamdi, it is likely that Doe v. Mattis will mark the first judicial endorsement of the claim that ISIS falls under the AUMF.


[1] Deb Riechmann, ACLU challenges detention of American ‘John Doe’ captured in Syria, Miami Herald, (Oct. 5, 2017),

[2] Id.

[3] Pet. For a Writ of Habeas Corpus, Am. Civil Liberties Union Found. v. Mattis (D.D.C. 2017); Order, Am. Civil Liberties Union Found. v. Mattis, No. 17-cv-2069 (TSC) (D.D.C. 2017).

[4] Authorization for the Use of Military Force, Pub. L. No. 107-40, 115 Stat. 224 (2001).

[5] Hamdi v. Rumsfeld, 542 U.S. 507, 517 (2004) (stating that “[w]e agree with the Government’s alternative position, that Congress has in fact authorized Hamdi’s detention, through the AUMF”).

[6] Id. at 510.

[7] Id.

[8] Resp’ts’ Mem. Regarding the Government’s Detention Authority Relative to Detainees Held at Guantanamo Bay, In Re: Guantanamo Bay Detainee Litigation, No. 08-442 (TFH) (D.D.C. 2009).

[9] Resp’ts Mem. Regarding the Government’s Detention Authority Relative to Detainees Held at Guantanamo Bay, p. 2 (Mar. 13, 2009).

[10] Al-Adahi v. Obama, 613 F.3d 1102, 1103 (D.C. Cir. 2010); Al-Bihani v. Obama, 590 F.3d 866, 871 (D.C. Cir. 2010); Khairkhwa v. Obama, 703 F.3d 547, 548 (D.C. Cir. 2012); Hussain v. Obama, 718 F.3d 964, 967 (D.C. Cir. 2013).

[11] National Defense Authorization Act for Fiscal Year 2012, Pub. L. No. 112-81, 125 Stat. 1298 (2011).

[12] Daniel L. Byman & Jennifer R. Williams, ISIS vs. Al Qaeda: Jihadism’s global civil war, Brookings Institution (Feb. 24, 2015),

[13] Non-Detention Act, Pub. L. No. 92-128, 62 Stat. 847 (1971).

[14] Hamdi v. Rumsfeld, 542 U.S. 507, 521 (2004).