Online Workshop Comment: Is Customary International Law Part of the “Law of the United States”?
I want to thank David again for agreeing to join us here at Opinio Juris for the next couple of days to discuss his forthcoming article (written with Curtis Bradley and Jack Goldsmith), “Sosa, Customary International Law, and the Relevance of Erie” (the “Article”). The Article demonstrates to me that Sosa has not ended the debate about CIL that Curt and Jack launched 10 years ago. I agree with you all that the Sosa Court has still not explained fully how or why CIL is integrated into the U.S. legal system post-Erie. On the other hand, neither does the Article, at least to my satisfaction.
On the other hand, I’m not sure I agree with the Article that the Sosa court resolved this question either way. Around Part IV.A. (pp. 21-22), the Article flatly declares, “As a result, Sosa eliminates one of the two central pillars on which the modern position rested — the notion that CIL was historically federal law and therefore outside Erie’s reach.” But the Sosa court studiously avoided any deep analysis of this question, probably because it didn’t have to do so in order to resolve the case before it. Its analysis recognized that CIL was treated as part of the “common law” but I don’t think a later Court is precluded from also concluding that CIL is a special kind of “common law” that the Founders recognized was also part of the “Law of the United States.” Those broad historical statements about CIL as the “Law of the Land” and the “Law of the United States” are still out there to be wielded in some future amicus brief.
This leads me, rather indirectly, to the question I wish the Article provided a fuller answer to: Does CIL, as interpreted by federal courts, bind the Executive Branch? If it is part of the “Law of the United States” in either Article III or Article VI of the Constitution, this is strong evidence of its binding effect. If not, then what domestic effect does CIL have on the Executive Branch?
The Article criticizes the Office of Legal Counsel’s famous 2002 opinion claiming that “any customary law of armed conflict in no way binds, as a legal matter, the President or the U.S. Armed Forces concerning the detention or trial of members of al Qaeda and the Taliban.” But the Article then goes ahead and endorses this conclusion as a matter of domestic (but not international) law. As I read the Article, CIL simply has no domestic binding effect on the President although it might bind him (and the country) on the international plane. The President is not bound by the Constitution to follow CIL.
This seems right to me, but I think critics are right that this is a strange situation. In this view, CIL is a kind of common law for domestic purposes, applied by federal courts in particular situations but never against the executive branch.
What happens if the executive branch is in a situation, like the Sosa case itself, where a federal court has the jurisdiction to apply CIL as common law under the Alien Tort Statute? Putting aside immunity issues, why is the executive branch bound here but not in other circumstances? Is it because Congress has incorporated CIL through the Alien Tort Statute? Is that the same theory for why the President is bound by CIL in Hamdan v. Rumsfeld?
If so, there is a pretty thin line between CIL lurking as a purely international obligation unenforceable in U.S. courts and CIL as a binding federal law that can invalidate U.S. drug interdiction policies in Sosa and U.S. military commissions in Hamdan. All it took was for Congress to include the magic phrase “law of nations” or “law of war” in a federal statute.
Moreover, the President’s power to interpret CIL on the international plane, which seems necessary given that for the most part it only bind him on the international plane, is subject to judicial second-guessing via this background federal court activity. The President can claim, on the international plane, that he believes that certain CIL rules do not apply to Al-Qaeda. But a federal court, as long as it is granted jurisdiction over claims brought under the “law of nations”, can simply override this interpretation. Isn’t this as much of a separation of powers problem as a modern position CIL-as-federal-law theory would create?
These anomalies lead me to believe that the Sosa court left at least half open the question of whether CIL can be considered part of the “Law of the United States” in some circumstances. The fact that CIL can in some circumstances be applied freely in federal courts in ways that do bind the Executive Branch will tempt the Court to adopt a theory of constitutional incorporation in Article III or even as part of the “Laws” the President is bound “Take Care” of in Article II. I think this is wrong and a bad idea to boot, but that hasn’t stopped the Court before.