As Wells Bennett noted on Friday over at Lawfare, attorneys for Abd al-Rahim al-Nashiri, a Guantánamo detainee facing capital charges before a military commission for his alleged role in the bombing of the USS Cole, have now filed a new habeas petition in the D.C. district court, seeking to block his trial on the ground that the United States was not in an armed conflict at the time of the attack, and so whether or not his alleged conduct was criminal, it could not have been a war crime subjecting him to prosecution by military commission. But whereas Wells noted that “al-Nashiri now seeks to advance, via habeas, roughly the same argument he advanced earlier (and unsuccessfully)” before the Ninth Circuit, there’s a critical distinction that makes this case worth watching. That difference is the D.C. Circuit’s intervening decision in Aamer.

In the Ninth Circuit, Nashiri’s claims–which were styled largely as a claim for mandamus or other extraordinary relief–were dismissed for lack of subject-matter jurisdiction, and not on the merits. In affirming the district court’s dismissal, the Court of Appeals relied on 28 U.S.C. § 2241(e)(2)–the non-habeas jurisdiction-stripping provision of the Military Commissions Act of 2006. I’ve previously criticized this analysis on several grounds, but the key for present purposes is that the Ninth Circuit, in so holding, relied upon an earlier decision that itself largely followed the D.C. Circuit’s analogous interpretation of § 2241(e)(2) in al-Zahrani. What’s different here is that Nashiri’s new claim is a habeas claim, which arguably triggers the habeas jurisdiction-stripping provision of the MCA, i.e., 28 U.S.C. § 2241(e)(1). And this is why Aamer is so significant: There, the D.C. Circuit held that Boumediene necessarily abnegated § 2241(e)(1) in all cases properly brought as habeas petitions–whether or not it would be unconstitutional as so applied. (In effect, Aamer held that Boumediene had invalidated § 2241(e)(1) on its face, at least as applied to the Guantánamo detainees.). As I’ve written previously, the upside of Aamer is that it returns habeas jurisdiction in the D.C. Circuit to the pre-MCA (and pre-Detainee Treatment Act) status quo (even as al-Zahrani continues to foreclose jurisdiction over non-habeas claims by current and former detainees). And, as the lower-court proceedings in Hamdan I illustrate (along with Part III of Justice Stevens’s majority opinion for the Supreme Court), that status quo allowed military defendants to use habeas to mount pre-trial challenges to military jurisdiction, so long as those challenges went to the military’s underlying jurisdiction (as Nashiri’s certainly appears to).

To be sure, the government will likely argue that, even if the district court has jurisdiction over Nashiri’s claims, it should abstain from resolving them under the Supreme Court’s 1975 decision in Schlesinger v. Councilman. I’ve elsewhere suggested why this argument is (or, at least, should be) unavailing. And so, whatever one thinks of the interesting and complicated merits of Nashiri’s claim (and just when the “armed conflict” with al Qaeda began), Aamer should clear the way for the D.C. district court to have to resolve those merits, sooner rather than later.