To Obama's credit, unlike Bush he has indicated that he is using the power to imprison without trial only reluctantly. In announcing his Guantanamo policy in May, Obama called the prospect of prolonged, indefinite incarceration "one of the toughest issues we will face." Yet rather than accept responsibility for making the choice to imprison without trial, Obama stated without explanation that some of the prisoners "cannot be prosecuted." He did not explain why trials were not an option. Certainly it cannot be the case that American law is incapable of dealing with al-Qaida agents or terrorism in general. Bush tried and convicted a number of al-Qaida terrorists during his presidency, and Obama is poised to do the same.
Many have speculated that Obama's refusal to try some of the prisoners stems from concerns that the evidence against them is the product of torture, and thus tainted. This kind of evidence has long been inadmissible at trial under what is known as the "exclusionary rule," which prohibits the use of evidence that has been acquired in violation of the Constitution. But if this is Obama's reasoning, he has effectively bifurcated the exclusionary rule, creating a regime where evidence secured through torture cannot be used at trial but can be used as the basis for incarcerating a suspect, even for the rest of his life.
Such a bifurcated exclusionary rule would create all the wrong incentives. Government interrogators will know that a confession secured through torture may serve as the basis for prolonged incarceration, despite the fact that Obama issued an order banning torture when he took office. This rule also would compound the wrongs suffered by some of those Guantanamo prisoners who were themselves tortured: They were subjected to excruciating pain, and now the fruits of that abuse will keep them in prison with no end in sight. The Constitution should not allow any deprivation of liberty to be based on evidence procured through torture, regardless of whether that deprivation is the result of a trial or the president's unilateral decision.
Alternately, the concern animating Obama's reluctance to go to trial may not be the use of tainted evidence but rather the disclosure of secret evidence in the course of prosecution. The government is, of course, entitled to a measure of secrecy, but that should not, and in fact never has, justified imprisonment without a trial. In a good number of criminal prosecutions touching on national security, defendants have sought information that the government deemed top secret. Courts have been more than capable of accommodating these concerns, typically by examining the evidence in private without the accused or his lawyer and evaluating its relevance to the case. If the judge determines that the evidence is important, the government can hand it over to the accused, offer a substitute, or drop the case. The remedy has never been never been to suspend the trial and incarcerate the prisoner indefinitely.
Nor can Obama's detention policy be justified on the ground of preventing some extraordinary harm, such as the detonation of a radioactive bomb. None of the Guantanamo prisoners are accused of conspiring to engage in such a crime. Even if they were, however, the burden would remain on the government to prosecute them for that crime, even if that carries a risk of acquittal. If the government is prepared to try an individual as dangerous and as committed to harming the people of this country as Khalid Sheikh Mohammed, how can it justify indefinite imprisonment of anyone else? The exceptions to the principle of freedom do not arise from the president's assessment on a case-by-case basis of the gravity of the threat posed if the prisoner is acquitted.
Neither torture, nor secrecy, nor the risk of acquittal excuse Obama from the choice he has made to imprison without trial. In the end Obama's assertion of his power to do so is no different than that of his predecessor. Perhaps sensing this, Obama initially sought to distance himself from Bush's unilateralism by promising to develop a system of "judicial and congressional oversight" of any executive decision to incarcerate a suspect indefinitely without a trial. As he said then, "in our constitutional system, prolonged detention should not be the decision of any one man." It is doubtful whether an oversight system, which would review only whether the president had acted reasonably, could ever satisfy the principle of freedom. But the sad fact is that Obama has not carried through on this promise and now presides over the very horror he himself had the courage to denounce.