Al-Marri's case is identical in most material respects legally to the more famous case of Jose Padilla, except that Padilla was a U.S. citizen, while Al-Marri was a legal alien. This makes the 4th Circuit's 2-1 ruling today holding that Al-Marri's detention as an enemy combatant is illegal very significant. Al-Marri is the only person publicly known to be held within the boundaries of the United States as an enemy combatant today.
The ruling holds that the Military Commissions Act of 2006 does not apply to Al-Marri, distinguishing a D.C. Circuit ruling that held that the act stripped courts of jurisdiction over detainees at Guantanamo Bay, basically on the grounds that Al-Marri was not provided with a combat status review tribunal review (and with a heavy hand in favor of Al-Marri to construe the statute in a manner that avoided a constitutional question).
It distinguished the Hamdi and Padilla cases from Al-Marri's case largely on the grounds that both Mr. Hamdi and Mr. Padilla were alleged to have taken up arms in Afghanistan, while Al-Marri was not alleged to have done so. In short, the core holding of the Al-Marri case is that civilians who coordinate with or support an enemy do not by doing so make themselves enemy combatants, even though they may have violated crimes applicable to civilians. Thus, the Civil War case Milligan, rather than Hamdi or Padilla or the World War II cases that underlie the governments case applies.
The ruling for Al-Marri is still narrow. It does not presume to look beyond the government's stated reasons for detaining a person, and does not address whether the courts can be deprived of jurisdiction in similar cases where a Combat Status Review Tribunal is convened by the government for someone detained in the United States (although even the D.C. Circuit holding validating the Military Commissions Act of 2006 ruled on a basis that would imply that in those circumstances that the Military Commissions Act of 2006 would be unconstitutional).
The United States Court of Appeals for the Fourth Circuit is a conservative venue and had the Padilla case on the books. It could easily have caved in the Al-Marri case as well, most easily on jurisdictional grounds. But, instead, it said that enough was enough.
In the end, the 4th Circuit orders the government is directed to release Al-Marri from military custody within "a reasonable period of time." It may release him entirely, charge him with a crime, commence proceedings to deport him, hold him as a material witness, or hold him for a limited period of time under the Patriot Act. This is less of an option that the Court's ruling would suggest, however. For the charges upon which Al-Marri was originally held, there are serious speedy trial, statute of limitations and time served issues. Should Al-Marri face new charges, there are issues of the taint the evidence against him may have of coercion used in obtaining evidence. Showing that Al-Marri is held in good faith as a material witness is difficult at this point, as he has been out of action for four years making his knowledge stale. And, Patriot Act detention is indeed for a limited period of time. Deportation of Al-Marri to Qatar is probably the most attractive option for the Government if it loses in the U.S. Supreme Court.
The dissent simply finds that the jurisdiction stripping provisions of the Military Commission Act of 2006 is unconstitutional in this case. But, the dissent finds that the enemy combatant designation was proper. The dissent finds that an allegation that someone is a sleeper agent sabateur is good enough.
An appeal to the U.S. Supreme Court is almost certain (eventually). How it will treat this case is not. Also, the Bush Administration may, as it did in the Padilla case, look for a way to moot this case before it reaches the U.S. Supreme Court as a form of damage control. It probably believed it was going to win this case, or it likely would have done so before a precedential opinion was issued in this case.
Update: SCOTUS Blog reports a request for en banc review in the 4th Circuit by the government, which apparently sees this as more friendly forum than SCOTUS apparently.