The combination of Jack's post and sleeping on the subject has mostly set my mind at ease on the difference between an executive order and a statute for purposes of the Guantanamo review system currently on the table--but not entirely.
A few considerations:
First, let us assume that the review system in this executive order will only cover Guantanamo and only cover those detainees there who lose their habeas cases, in other words those whose detentions are clearly lawful. I think this is almost surely right on both counts. So in this new world, habeas would remain the front-line system for detention adjudication, with this executive order providing a kind of additional layer of voluntary review. It is, I readily concede, far less important to have this layer in statute than it would be if we were talking about the front-line review system. What's more, as Jack rightly points out, it is all but impossible to imagine that a Congress bent on preserving Guantanamo would enact a worthy back-end review system that could conceivably end up releasing some people. Indeed, the absence of just such a provision was one of Bobby and my complaints about Sen. Lindsey Graham's habeas bill, S. 3707 (though we suggested that review should occur twice annually for reasons of international law compliance). And finally, my expressed concerns about the system's instability before the courts are, on reflection, overstated. After all, what is a person whose detention has already been affirmed by the court system going to complain about with respect to this new system--that the President has chosen voluntarily to give him a little more process? that he would have preferred more process still? that the process he got yielded (from his point of view) the wrong outcome?
Those points conceded, I still worry. For one thing, Jack's de minimis account of the difference between a statute and an executive order treats only the litigation differences between them. There are other differences. One of them goes to democratic spirit. Are we a country that aspires to actually govern itself on hard questions and build institutional arrangements to confront novel circumstances or are we a country that says we do but that, in fact, defaults to raw presidential power when it comes down to it. This is the question that animated my book, Law and the Long War, and the fact that in this instance presidential power would be used to grant process, not to deny it, and legislative power would (likely) frustrate that ambition is only mild comfort. There is something ugly about building a large edifice of detention on the basis of law, even good law, promulgated by decree. Don't get me wrong. I'm not against executive orders, and I'm not saying a review system based on one would be improper, illegal, or dictatorial. I'm saying merely that it is not the system for which one would pray or to which a democratic nation should aspire. Take that for what it's worth.
Second, while I probably overstated my earlier point about system instability, there is a kernel of it that continues to gnaw at me. Consider the overall architecture of the system this executive order will create. A detainee at Guantanamo--and only at Guantanamo--after some period of detention files a habeas suit. This suit takes some years to litigate, during which time the government argues that the increasingly-antiquated AUMF, which nowhere spells out the scope of the detention it permits, authorizes his detention. After the detainee loses this case, assuming he does, this executive order presumably kicks in and gives him and his lawyers an annual opportunity to make their case for what amounts to parole. Meanwhile, the comparable detainee not lucky enough to have been shipped to Guantanamo once upon a time, faces a completely different system, one with no judicial review at all and no elaborate executive order-based adversarial system either. The absence of any comprehensive, rational, statutory approach to detentions in general will, I fear, create litigation instability in the long run; this instability will likely not show up in the Guantanamo litigations themselves. Those will be held up as the standard to which other detentions should now conform. The problem will thus arise in the effort to extend federal court jurisdiction and other review systems beyond Guantanamo. The more elaborate the processes for Guantanamo detainees become relative to those for others, and the less care we take to establish rational connections between the systems, the more difficult it will become to defend our detention system as a whole. For why exactly does this executive order--or at least something like it--not apply elsewhere?
I can imagine answers to this question, but they are answers based on a very different policy than our current model. They are not answers that this administration--or, for very different reasons, the last administration--would want to put on the table. For example, I could imagine (and support) a national policy in which all detainees whom we imagined holding long-term would come to Guantanamo (or Illinois or wherever) and be subject to judicial review process followed by a long-term review system and all other detainees stayed in theater with lesser process. But that would require admitting that the Guantanamo problem is not some isolated legacy issue left over from the last administration but rather a piece of a larger system of detention to which we are committed for the foreseeable future. It would also require admitting that Guantanamo--or whatever replaces it--is not merely not going to close but likely at times to expand. It's population would ebb and flow with new captures, new release and transfer opportunities for individuals and groups, new threats, and new military operations.
An executive order for Guantanamo alone in the absence of any rational systemic design is a part of a delusional insistence that Guantanamo is separate from the larger questions of detention policy. It isn't--or, at least, we cannot count on its being so. Building a non-statutory edifice for one corner of a system is a pale substitute for thinking through seriously what that system should look like and writing that system into law.