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Gul v. Biden: Habeas Corpus and the Associated Force Doctrine in Guantanamo Bay Litigation

Anastasia Bradatan
Monday, November 14, 2022, 8:01 AM

Judge Mehta’s 2021 decision granting Guantanamo Bay detainee Asadullah Haroon Gul’s writ of habeas corpus defines what the government must show to prove that a member of a former “associated force” should also be considered a part of al-Qaeda.

A Puerto Rico Army National Guard member in a watchtower at the Guantanamo detention facility (Photo by U.S. Air Force Senior Airmon Gino Reyes,; United States Government Work,

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On June 24, the U.S. government transferred Asadullah Haroon Gul (aka Haroon al-Afghani) to Qatar, which has played a significant role in facilitating U.S.-Taliban relations. Qatari officials then turned him over to Taliban representatives. The transfer comes after years of litigation, written about previously on Lawfare, which began with Gul’s habeas petition filed in 2016. In announcing its decision to repatriate Gul on June 24, the Department of Defense cited both the Periodic Review Board’s (PRB’s) Oct. 7, 2021, determination that Gul was eligible for transfer and Judge Amit Mehta’s Oct. 18, 2021, decision granting Gul’s petition for writ of habeas corpus. 

Gul’s recent release is a good opportunity to revisit the legal basis for Mehta’s grant of his habeas petition, which was the first grant of a Guantanamo detainee’s habeas petition in many years. The decision raises complex legal issues that shed some light on why a man who was never charged with a crime nevertheless spent 15 years at Guantanamo, despite the former “associated force” he was part of declaring peace with the Afghan government in 2016. The decision also helps shed light on why it took six years to adjudicate his claims. A separate but related difficulty arose when the Taliban took over the Afghan government on Aug. 15, 2021, which contributed to the delay between Mehta’s grant of Gul’s habeas petition in October 2021 and his actual transfer on June 24. 

Case Overview

Gul had been captured in 2007 by Afghan government forces, and the U.S. government detained him at Guantanamo Bay pursuant to the authority of the 2001 Authorization for the Use of Military Force (AUMF). More specifically, the U.S. government detained Gul based on its assessment that he acted as a courier for senior al-Qaeda membership and because of his senior commander status in Hezb-e-Islami Gulbuddin (HIG), a terrorist group that has been affiliated with al-Qaeda. 

The U.S. Court of Appeals for the District of Columbia Circuit has interpreted the AUMF to authorize the president to use all necessary and appropriate force against nations or entities involved in the planning or execution of Sept. 11, 2001, as granting authority to detain members of a force “associated” with al-Qaeda or the Taliban. The Gul court noted that the D.C. Circuit has not defined what constitutes an associated force, so it turned to the nonbinding but legally persuasive decision Hamlily v. Obama, in which the U.S. District Court for the District of Columbia defined an “associated force” by relying on co-belligerency, a law of war principle that pertains to an international armed conflict setting. Co-belligerency takes place when a state becomes “a fully fledged belligerent fighting in association with one or more belligerent powers” and thereby violates the requirement to stay neutral (that is, impartial) in a war. In the context of the armed conflict against al-Qaeda and the Taliban, which is considered a non-international armed conflict, the Hamlily court and the U.S. government applied the term to organized armed groups that fight alongside al-Qaeda and are a co-belligerent with al-Qaeda in hostilities against the United States or its coalition partners. Defending the Taliban and harboring al-Qaeda is enough for an organization to constitute an associated force, as the D.C. Circuit Court found with the 55th Arab Brigade in Al-Bihani v. Obama

In 2016, Gul filed a habeas petition. He initially rejected the government’s characterization of him, arguing that the U.S. government was mistaken about his identification because he was not a member of either al-Qaeda or HIG. Following the 2016 peace agreement between the Afghan government and HIG, however, Gul amended the petition in June 2018 to argue that even if he were an HIG member, his HIG membership could no longer be used as grounds to detain him. 

In 2018, the Department of Justice “withdrew its reliance on Gul’s membership in HIG as the legal justification for his detention position” but maintained that while the U.S. government could no longer detain Gul based solely on his HIG membership, it nevertheless was authorized to detain Gul based on his involvement with al-Qaeda. The Justice Department likely shifted its position because after HIG and the Afghan government reached a peace agreement in 2016, HIG might no longer qualify as an associated force under the AUMF (or so Judge Mehta inferred in his opinion).

The government claimed that Gul remained detainable “because he was functionally a member of al-Qaeda or, in the alternative, a substantial supporter of al-Qaeda.” Ultimately, this was the novel question before Mehta: “whether a member of an associated force, in this case an HIG member, remains detainable even after his force declares peace because his actions as a member of that associated force make him legally part of or a substantial supporter of al-Qaeda.” 

While Gul’s case was proceeding in the district court, the Periodic Review Board process was underway, through which an interagency team decides whether a detainee can be safely removed from Guantanamo Bay regardless of whether the detainee is being lawfully detained. On Oct. 7, 2021, the PRB determined that Gul was eligible for transfer. 

Days later, on Oct. 18, 2021, Mehta denied Gul’s petition for immediate release, in which Gul had argued that President Biden’s announcement that the United States would withdraw from Afghanistan signified the end of the active hostilities that were the basis of his detention under the 2001 AUMF. Therefore, Gul asserted that the United States had lost the authority to detain him at all. Mehta found that the court must give the highest level of deference to the executive’s position that active hostilities continue to exist. Thus, he concluded, the government’s detention authority under the 2001 AUMF remained intact. 

Ultimately, Mehta granted Gul’s petition for writ of habeas corpus, which, unlike the petition for immediate release, was based on facts applicable solely to Gul. He found that the United States lacked the legal authority to detain Gul given that the United States has been at peace with HIG since 2016 and that Gul had acted as a member only of HIG during the Afghan conflict. As a preliminary matter, the court accepted the government’s record as presented and rejected Gul’s assertions that the government’s evidence was unreliable due to hearsay, insufficient evaluation, language and cultural issues, lack of sufficient sources, or because the evidence was induced through torture. In regard to the government-produced interrogation reports, the court, relying on D.C. Circuit precedent, applied a “presumption of regularity."

HIG and Gul’s Relationship With al-Qaeda

Key to Mehta’s ruling was his determination of the nature of Gul’s relationship with al-Qaeda—in particular, whether it surpassed the bounds of HIG’s relationship with al-Qaeda such that his detention could be premised not on his membership in a former associated force but, rather, on the more solid ground that his own connection to al-Qaeda brought him more directly within the AUMF’s ambit. 

Mehta provided a comprehensive overview of the facts relevant to this question. As written previously by others on Lawfare, Gul, an Afghan citizen, grew up in a refugee camp administered by HIG, a terrorist organization led by Gulbuddin Hekmatyar, and later became a member of the group. Through HIG, Gul received food, money, an education, and military training, through which he forged a relationship with an al-Qaeda explosives expert. Gul also became a member of a religious student organization named Sipah I-Danesh, through which he received weapons training, and which was made up of members who, like Gul, ended up becoming al-Qaeda facilitators. 

From 2001 to 2003, Gul, at the behest of Hekmaytar, traveled to Tora Bora along with 11 other HIG members to help Osama bin Laden escape from Afghanistan. Gul also assisted al-Qaeda operatives enter the Afghan province of Nangarhar and subsequently couriered correspondence and funds for them for about a year. During this time frame, Gul was introduced to Hadi al-Iraqi, al-Qaeda’s chief of military operations, and carried out numerous tasks for him, including transferring medicine, funds, and other materials. In return, he asked al-Iraqi to connect a friend of his from another militant group with al-Qaeda members in Afghanistan.

Gul claimed that his relationship with al-Qaeda deteriorated around 2004 and stated in interrogations with U.S. government officials that he had limited contact with al-Qaeda members in the 12-14 months preceding his capture in February 2007. One such contact included Abu Basir, one of the al-Qaeda commanders in Jalalabad, Afghanistan, who in 2006 sent him a letter asking for his “‘assistance in locating weapons that were supposed to have been acquired’ for three al-Qaeda operatives traveling to Nangarhar.” Gul denied knowing about the weapons acquisition or responding to the letter. From 2004 until his capture in 2007 in Nangarhar, Gul was an HIG commander of operations in Nangarhar and was positioned to be promoted to an elite force within HIG that would focus on high-level attacks within Afghanistan, a more coordinated political activism, recruitment, and training. 

Merits: The Government’s Arguments in Detaining Gul and the Court’s Grant of Gul’s Habeas Petition

After the government amended its argument to drop the claim that Gul could be detained on the basis of his membership in HIG, it provided three justifications for continuing Gul’s detention. First, the government contended that Gul’s HIG-sanctioned activities made him a part of al-Qaeda under the “functional test.” Second, it argued that Gul exceeded the scope of his HIG-sanctioned activities in the services he provided al-Qaeda and therefore became a part of al-Qaeda. Finally, it argued that Gul “substantially supported” al-Qaeda according to standards set out by the 2012 National Defense Authorization Act (NDAA). 

The Government’s First Argument 

In its first argument, the government claimed that even if Gul had technically acted as a member of HIG, the nature of his activities rendered him a part of al-Qaeda under the functional test, which is outlined in the D.C. Circuit’s ruling in Bensayah v. Obama. The test entails doing a case-by-case determination that involves looking at the individual’s actions toward al-Qaeda and not just at whether an individual is a part of al-Qaeda’s formal command structure. The Bensayeh court found that although being a part of the formal command structure would be sufficient to fulfill the functional test, it is not necessary. According to the government, some—but not all—members of “associated forces” like HIG were more properly understood as members of a “primary force” like al-Qaeda. To differentiate, the government proposed conceptualizing three buckets of HIG members: “HIG members doing HIG things for HIG purposes,” HIG “members doing HIG things for al-Qaeda purposes,” and “HIG members doing al-Qaeda things for al-Qaeda purposes.” The government argued that an individual could be detained under the associated force doctrine for his membership with the associated force only if he were to fall under the first bucket. 

The court, in rejecting the government’s first argument, found that the government’s framework was incompatible with the language of the 2012 NDAA. The court noted that the text of the 2012 NDAA differentiates between al-Qaeda, the Taliban, and associated forces. Were the government’s argument to be adopted, the term “associated force” would become redundant, since any member of an associated force would be a part of al-Qaeda by performing the actions that makes the two forces associated. Mehta found that such an outcome would be improper under Alaska Department of Environmental Conservation v. EPA, which states that “a statute ought, upon the whole, to be so construed that, if it can be prevented, no clause, sentence or word shall be superfluous, void, or insignificant.” 

The court also rejected this first argument as incompatible with the reasoning behind the associated force doctrine. It found that although the government’s three-bucket analysis allowed for differences between associated forces and primary forces, its “double-counting theory in this case [ran] aground on the law of war principles of co-belligerency” and the “government’s position that Gul’s actions as a member of HIG also made him ‘a part of’ al-Qaeda [was]… firmly at odds with the Geneva Conventions and the ‘law of war.’” The court further noted that Gul, as a member of a former associated force that has been at peace with the United States since 2016, should benefit from the legally significant act of his organization’s peace declaration. Otherwise, Gul would be considered as engaging in hostilities as long as the primary force (al-Qaeda) remained engaged in hostilities, “unless he took additional, affirmative steps to disassociate from the primary force.” Requiring Gul to take affirmative steps to disassociate in this way would clash with a law of armed conflict principle that states that “co-belligerents do not lose their separate identity merely by joining the fight with another force.” 

Finally, the court pointed to the Geneva Convention Relative to the Treatment of Prisoners of War, a treaty fundamental to the law of armed conflict that requires prisoners of war to be “released and repatriated without delay after the cessation of active hostilities.” The treaty’s commentary, which although only persuasive and not enforceable, specifies that the “obligation to release and repatriate prisoners of war arises as soon as active hostilities between the Detaining Power and the Power on which the prisoners depend have ceased” and that this holds true even when active hostilities continue with other parties to the conflict. 

The Government’s Second Argument 

In addressing the government’s second argument, the court considered whether Gul, as a member of HIG, exceeded the scope of his membership through his association with al-Qaeda to the point of becoming an al-Qaeda member. The court first discussed the 2001 AUMF, which, it held, “give[s] the Executive the authority to detain individuals who were a part of al-Qaeda, the Taliban or associated forces that have engaged in hostilities against the United States.” The court next turned to the 2012 NDAA through which Congress stated that the 2001 AUMF gave U.S. armed forces the authority to detain covered persons “under the law of war without trial until the end of the hostilities authorized by the” 2001 AUMF. Under the 2012 NDAA, a covered person includes “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 who has directly supported such hostilities in aid of such enemy forces.” 

The court noted that neither the 2001 AUMF nor the 2012 NDAA provides a standard for when an individual is said to be “a part of al-Qaeda,” nor does it define what “associated forces” means—and, therefore, looked to circuit precedent in interpreting both terms. As mentioned above, the Bensayah court developed a functional test, as opposed to taking a formal approach, to determine when an individual is considered to be a part of al-Qaeda. In Al Odah v. United States, Uthman v. Obama, Al-Madhwani v. Obama, and Awad v. Obama, the D.C. Circuit considered an individual to be a part of al-Qaeda by applying the functional test and considering factors. For example, were the individual’s travel patterns similar to those taken by individuals who want to join the Taliban and al-Qaeda? Was the individual captured in an area in which al-Qaeda was active and in the company of Taliban and al-Qaeda fighters? Did the individual stay in an al-Qaeda guesthouse? Did the individual attend an al-Qaeda training camp?

Having established that Gul was not detainable as a member of an associated force that was no longer engaged in hostilities with the United States, the court then analyzed whether Gul was nevertheless detainable for being a part of al-Qaeda. Because the 2012 NDAA provides that “a detainee who is acknowledged to be a member of an associated force and engages in traditional acts of co-belligerency does so in his capacity as a member of an associated force,” the government argued that Gul engaged in activity that HIG had not agreed to undertake in support of al-Qaeda and therefore exceeded his role in the HIG-al-Qaeda alliance. 

A significant portion of the government’s evidence in support of this claim was redacted in the court’s decision, but the publicly available portions include Gul’s responses during interrogations. Gul may have been working on behalf of al-Qaeda, the government suggested, pointing to the many high-level al-Qaeda members whom he knew. 

Although the court acknowledged that such associations are normally probative of al-Qaeda membership, it concluded that the government had failed to show that Gul exceeded the scope of HIG’s co-belligerency because it had not shown that Gul had any contacts beyond those that resulted from his role as a HIG operative. 

The court found the government’s other argument—that Gul exceeded his role in the HIG-al-Qaeda alliance through the additional actions he took to support al-Qaeda—more compelling but nevertheless concluded that this did not justify Gul’s continued detention. The government had argued that Gul’s actions were not authorized by HIG and that his conduct, including facilitating al-Qaeda operatives into Nangarhar province in 2002 and his alleged affiliations with al-Qaeda in 2006, exceeded the scope of his HIG membership. The government’s argument was based on Gul’s interrogation reports, in which he repeatedly used the word “unofficial” to describe certain relationships. For instance, he used the words “unofficial liaison” to describe the Nangarhar facilitation and expressed his belief that “HIG facilitated the Arabs and Tajik in Nangarhar Province unofficially at the direction of Maulawi Humdullah and Hajji Abdul Ahad” (court citing to the government’s record, emphasis added by Judge Mehta). Similarly, Gul stated that he established some “unofficial liaisons” with Taliban forces in Nangarhar province led by Anwar al-Haq Mujahid, the commander of the Taliban subgroup Tora Bora Military Front. According to the government, these statements showed that Gul was acting beyond his role as a member of HIG; it defined “unofficial” as “a relationship that was neither in HIG’s interests, nor undertaken in [Gul’s] capacity as an HIG commander.”

The court rejected the government’s proposed definition of “unofficial,” finding that Hekmatyar was aware of Gul’s relationship with the Taliban and that Gul conducted the Nangarhar facilitation per his HIG commander’s order. 

The Government’s Third Argument

Finally, the court considered the government’s argument in the alternative: If Gul was not a part of al-Qaeda, could the United States nevertheless detain him on the ground that he had provided “substantial support” to al-Qaeda within the meaning of the 2012 NDAA? The government had argued that members of a different or associated force can meet the “substantial support” prong “so long as they are not a member of the force they are accused of supporting, they are detainable as a substantial supporter.” 

The court, however, ultimately sided with Gul, holding that only civilians can provide “substantial support” to al-Qaeda, thereby excluding the possibility that Gul, who was a co-belligerent of al-Qaeda, provided substantial support. As a co-belligerent, Gul could not also be a civilian—which in the U.S. Court of Appeals for the Second Circuit case that Mehta discusses, Hedges v. Obama, the Justice Department defined as those who assist military forces and “civilian members of military aircraft crews, war correspondents, supply contractors, members of labour units or of services responsible for the welfare of the armed forces.” The D.C. Circuit has upheld detention on the basis of the “substantial support” prong only where civilians provided “substantial support” to al-Qaeda, such as in Al-Bihani v. Obama, where the petitioner served as a cook who carried a brigade-issued weapon, and in Paracha v. Trump, where the petitioner was a businessman who “provided financial and other support to members of the Taliban and al-Qaeda.”


Based on the current 2001 AUMF, Judge Mehta has set a detailed framework that can be applied to members of a former associated force. In particular, his decision signals to the government the challenges it may face in using the functional test and in alleging that an individual is a part of al-Qaeda. Additionally, as related to the 2012 NDAA, Mehta demonstrates a commitment to keeping separate the categories of al-Qaeda, the Taliban, and associated forces, which indicates that the government should be cautious in making future arguments that collapse the three prongs under the 2012 NDAA.

Anastasia Bradatan is a JD Candidate at Georgetown University Law Center. She has worked at U.S. Citizenship and Immigration Services for two years prior to attending law school and is a member of the Georgetown Immigration Law Journal. She attended the University of Texas at Austin, where she received her BA in International Relations, Spanish- Portuguese and Hindi.

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