590 F.3d 866 (D.C. Cir. 2010)
Al-Bihani v. Obama is one of the earliest and most influential post-Boumediene decisions from the U.S.
Does the AUMF authorize the continued detention of a noncitizen who was part of or substantially supported Taliban/al Qaeda forces, and, if so, are the international laws of war binding limitations on that authority or on habeas procedures, including the standard of proof and admissibility of evidence in Guantánamo habeas cases?
Under the AUMF, the Executive may detain individuals who were part of, or substantially supported, the Taliban, al Qaeda, or associated forces engaged in hostilities against the United States or its coalition partners, as a fundamental incident of the use of force recognized in Hamdi v. Rumsfeld. International law, including the law of war and the Geneva Conventions, is not an independent, binding limitation on that statutory authority in domestic courts unless Congress has incorporated such norms into domestic law. In habeas proceedings for Guantánamo detainees, the government's burden may be satisfied by a preponderance of the evidence, and courts may consider hearsay and intelligence reports, assessing reliability rather than applying the formal rules of evidence.
The D.C. Circuit affirmed the denial of habeas. It held that the AUMF authorized Al-Bihani's detention based on evidence that he was part of or substantially supported enemy forces. The court further held that the international laws of war do not independently limit the AUMF's detention authority in domestic habeas litigation, and that the preponderance-of-the-evidence standard and flexible evidentiary rules employed by the district court were proper.
Al-Bihani is a pillar of the D.C. Circuit's Guantánamo jurisprudence. It operationalized the AUMF's detention authority by embracing the "part of"/"substantial support" framework, set a baseline preponderance-of-the-evidence burden for the government, and endorsed flexible evidentiary practices suited to national security cases. It also sparked an enduring debate about the role of international law in domestic habeas litigation: although later opinions treated the panel's broad statements as dicta, Al-Bihani marks a high-water line for the proposition that the AUMF—rather than international norms—controls in U.S. courts unless Congress provides otherwise. For law students, the case is essential to understanding the intersection of separation of powers, statutory interpretation, habeas procedure, and national security.