(a) Writs of habeas corpus may be granted by the Supreme Court, any justice thereof, the district courts and any circuit judge within their respective jurisdictions . . . .
(c) The writ of habeas corpus shall not extend to a prisoner unless
(1) He is in custody under or by color of the authority of the United States or is committed for trial before some court thereof; or . . .
(3) He is in custody in violation of the Constitution or laws or treaties of the United States . . . .
28 U.S.C. § 2241 (2000).
There remains the possibility that the standards we have articulated could be met by an appropriately authorized and properly constituted military tribunal. Indeed, it is notable that military regulations already provide for such process in related instances, dictating that tribunals be made available to determine the status of enemy detainees who assert prisoner-of-war status under the Geneva Convention. . . . In the absence of such process, however, a court that receives a petition for a writ of habeas corpus from an alleged enemy combatant must itself ensure that the minimum requirements of due process are achieved.
Id. (citations omitted). It is important to clarify that this would be a far different tribunal system from the military commissions authorized in President Bushs November 13, 2001, Military Order, which are often also referred to as military tribunals. Exec. Order, supra note 7, at 57,834. The Bush order sets up commissions meant to try charges of criminal violations and assess criminal penalties, including the death penalty. The Hamdi-inspired tribunals are meant to provide an administrative forum for deciding whether the detainee may continue to be held in the preventive detention (similar to that customarily employed for prisoners of war in more conventional conflicts) that the executive branch apparently contemplates for most of those detained as enemy combatants, both at Guantanamo and at other U.S.-run foreign facilities. To date, however, these tribunals have been established only at Guantanamo.
the position that the courts must forgo any examination of the individual case and focus exclusively on the legality of the broader detention scheme cannot be mandated by any reasonable view of separation of powers . . . . Thus, while we do not question that our due process assessment must pay keen attention to the particular burdens faced by the Executive in the context of military action, it would turn our system of checks and balances on its head to suggest that a citizen could not make his way to court with a challenge to the factual basis for his detention by his government, simply because the Executive opposes making available such a challenge.
Id. at 2650.
As the Government itself has recognized, we have utilized the some evidence standard in the past as a standard of review, not as a standard of proof. That is, it primarily has been employed by courts in examining an administrative record developed after an adversarial proceedingone with process at least of the sort that we today hold is constitutionally mandated in the citizen enemy-combatant setting. This standard therefore is ill suited to the situation in which a habeas petitioner has received no prior proceedings before any tribunal and had no prior opportunity to rebut the Executives factual assertions before a neutral decisionmaker.