Kevin Heller claims that the D.C. Circuit in its al-Bihani panel opinion has reached the conclusion, with which he agrees, that “there [is] no justification for the government’s attempt . . . to import the concept of co-belligerency into non-international armed conflict.” He adds: “Given the D.C. Circuit’s conclusion in Al-Bihani, why is the government still relying on the discredited notion of co-belligerency in Al-Aulaqi?”
The answer is that the D.C. Circuit has not done what Heller thinks it has done.
First, Judge Brown in the panel opinion rejects reliance altogether on the laws of war as a tool to inform the meaning of the AUMF. The court in the passage Heller cites was not dismissing the co-belligerency idea as an amplification of the AUMF, but rather dismissing it as a limit on the AUMF. For Judge Brown, the question is what the AUMF authorizes regardless of what the laws of war permit; she wants to expand the AUMF, not limit it. I doubt that Heller agrees with that.
Second, the reason the government continues to rely on co-belligerency is that a majority of the judges on the D.C. Circuit, in denying en banc rehearing, expressed the belief that the panel’s discussion of the laws of war was “not necessary to the disposition of the merits.” The government has probably concluded that the co-belligerency discussion in the panel opinion was a dictum that is not the law of the D.C. Circuit.
More generally, the government and the lower courts appear to be operating on the principle that, where the laws of war for a non-international armed conflict (NIAC) say little about a matter (such as, perhaps, neutrality), the laws of war for an international armed conflict (IAC), which say quite a lot about neutrality, should apply by analogy to inform the construction of what is “necessary and appropriate” under the AUMF, both as to what the AUMF authorizes and to the limits of what it authorizes. Heller seems to want to reject this analogical reasoning. But his position may lead him to a place he doesn’t want to go. For if the laws of war for NIAC are silent on an issue, the main alternative to arguing by analogy to IAC in interpreting the AUMF is to conclude that the laws of war place no limits whatsoever on the AUMF.