The Supreme Court (not unexpectedly) denied Jose Padilla's cert petition today. Interestingly, it appears that three Justices (Breyer, Souter, and Ginsburg) voted to hear the case, although only Justice Ginsburg published a dissent from the denial of the cert petition. (Such a dissent is rare.) Moreover, Justice Kennedy wrote an opinion concurring in the denial of the petition, which was joined by Chief Justice Roberts and Justice Stevens (who might have been expected to have been the fourth vote to hear the case).
In the underlying case, Padilla challenged the government's substantive power to detain him as an enemy combatant. (I blogged about the underlying Fourth Circuit opinion here.) Justice Kennedy noted that even if Padilla were to get the relief that he seeks, his current status would not change, because the government has shifted him out of military detention into the criminal justice system. Therefore, Justice Kennedy concluded that the case was moot. Justice Kennedy does suggest that if the government were to seek to shift him back to military detention, the federal courts would be prepared to act to protect his interests. However, Justice Kennedy doesn't really rxplain the mechanism by which this would occur. (In a bit of shameless self-promotion, I'll just note that this is the subject of my current paper, which I'll post to SSRN soon.)
The essence of Justice Ginsburg's argument was that the case was not moot, since it was only the government's voluntary cessation of the allegedly illegal activity that altered the circumstances.
In reading these opinions, I'm reminded a bit of City of Los Angeles v. Lyons, 461 U.S. 95 (1983), a case in which mootness and ripeness get conflated together into a standing opinion. Lyons concerned an effort to enjoin the LAPD's use of the "chokehold," brought by a plaintiff who had himself been subjected to this practice. The Court held that he lacked standing to seek injunctive relief, but the opinion can also be read as one about mootness and ripeness. Lyons' claim for injunctive relief was moot if based on the prior incident, and not ripe if based on fear of future subjection to the chokehold.
Of course, Lyons was permitted to seek damages under section 1983, and thereby litigate the constitutionality of the chokehold. My wife asked whether Padilla would be permitted to bring an action under Bivens (the analogue to section 1983 when seeking damages for constitutional violations by federal actors). If he could, then he could litigate the constitutionality of his prior detention as an enemy combatant.
My guess is that Padilla would be barred by Heck v. Humphrey, 512 U.S. 477 (1994), which bars section 1983 actions that would have the effect of reversing or invalidating a conviction, unless the prisoner has already succeeded in invalidating the conviction through a habeas corpus petition. There are some important differences, but Heck speaks of "conviction or imprisonment," and if anything, the wartime nature of detention might counsel greater deference to the government than in the usual context of imprisonment pursuant to conviction.
On the other hand, the criminal defendant automatically gets a venue in which to challenge the government's right to imprison him, whereas Padilla has been fighting for that right for years. Still, the habeas analogy would seem to deny him relief, because his inability (now) to invalidate the prior detention is due to his no longer being in such detention. While prisoners who have served their sentence can still seek habeas relief if they can show that they still suffer disabilities and burdens due to the fact of conviction, see, e.g., Carafas v. LaVallee, 391 U.S. 234 (1968), here, Padilla does not appear to suffer any cognizable, continuing disabilities or burdens as a result of the prior detention.
Anyway, this is just my quick impression of how things stand, so if you have any thoughts, please comment away.