Writing in The New York Times last Friday, Curt Bradley and Jack Goldsmith argued that the Justice Against State Sponsors of Terrorism Act (JASTA) would “violate a core principle of international law,” the principle of foreign sovereign immunity. At Lawfare, former State Department Legal Adviser John Bellinger seconded their assertion. Earlier in the week, White House Press Secretary Josh Earnest expressed similar concerns. (For a good primer on JASTA and its background, see Steve Vladeck’s post here.) The amount of legal analysis one can fit into an op-ed is necessarily limited, and it would be welcome to see Curt, Jack, John, or others flesh out the argument. But, in my view, there are serious problems with the assertion that JASTA would violate customary international law governing sovereign immunity, problems that raise more general questions of how one identifies rules of customary international law.

Curt and Jack summarize their international law argument this way: 

A nation’s immunity from lawsuits in the courts of another nation is a fundamental tenet of international law. This tenet is based on the idea that equal sovereigns should not use their courts to sit in judgment of one another. Many nations have tacitly agreed to limit immunity in specified contexts, such as when they engage in certain commercial activities. But apart from those exceptions (or where a binding treaty or Security Council resolution otherwise dictates), international law continues to guarantee immunity, even for alleged egregious crimes.

The first question to ask is where this fundamental tenet of international law comes from. I believe it is common ground that — as the Restatement (Third) of Foreign Relations Law puts it — “[c]ustomary international law results from a general and consistent practice of states followed by them from a sense of legal obligation.” If one looks at state practice with respect to foreign sovereign immunity, one finds some situations in which states are consistently held to be immune from the jurisdiction of the courts of other states, other situations in which states are consistently held not to be immune, other situations in which the practice is mixed, and still other situations in which there is no practice at all. How should one make sense of this practice?

Curt and Jack’s approach with respect to foreign sovereign immunity seems to be to infer a general rule of immunity based on state practice granting immunity and to treat the state practice denying immunity as establishing exceptions to the general rule. Where the practice is mixed or non-existent, the general rule of immunity would govern because there is not a “general and consistent practice of states” sufficient to create an exception. Of course, this is not the only possible way to read the existing state practice. One could instead infer specific rules of immunity only in those situations where there is a general and consistent practice of granting immunity. Under this approach, where the practice is mixed or non-existent, a general rule of non-immunity would govern. As Curt has recently written on page 34 in his excellent contribution to the book Custom’s Future, one must “necessarily make choices about how to describe [state practice], which baselines to apply in evaluating it, and whether or when to extend or analogize it to new situations.” I agree. My point is simply that the choices Curt and Jack have made in their analysis of sovereign immunity are choices — and they need to be defended.

One way to defend their approach would be to invoke the International Court of Justice’s 2012 decision in the Jurisdictional Immunities Case (Germany v. Italy), which took a similar approach to questions of sovereign immunity. But the ICJ took this approach because the state parties to the dispute both agreed on it. See paragraph 61 (“Both Parties agree that States are generally entitled to immunity in respect of acta jure imperii.”). In light of the parties’ agreement, the ICJ was certainly justified in starting with a general rule of immunity and then looking for state practice sufficient to support exceptions. But as Curt again has reminded us in his contribution to Custom’s Future, “ICJ decisions are technically binding only on the parties and thus should not automatically be treated as the last word by the international community on the content of [customary international law]” (p. 59).

Even if one adopts Curt and Jack’s basic approach to sovereign immunity, there remains the question of how broadly or narrowly to read the state practice creating exceptions to the general rule. There is lots of state practice supporting a territorial tort exception to sovereign immunity — that is, an exception for torts that occur in the nation that would exercise jurisdiction over the foreign state. (See Jurisdictional Immunities paragraphs 62-79.) This is what allows Americans injured in traffic accidents by a foreign government employee to sue the foreign state for damages. One might argue that this state practice should be read narrowly to apply only in these sorts of situations. But states that have codified the exception have done so in general terms applicable to any tort.

The US Foreign Sovereign Immunities Act (FSIA) also codifies the territorial tort exception in general terms. (See 28 U.S.C. § 1605(a)(5).) But US courts have interpreted it to require that the “entire tort” occurs within the United States. (See the Second Circuit Court of Appeals 2013 decision from In re Terrorist Attacks on September 11, 2001.) It is this limitation that JASTA would remove. JASTA would still require that there be “physical injury or death, or damage to or loss of property, occurring in the United States,” but it would make clear that the territorial tort exception applies “regardless of where the underlying tortious act or omission occurs.”

Customary international law does not seem to require the “entire tort” limitation. Article 12 of the United Nations Convention on Jurisdictional Immunities of States and Their Properties would apply the territorial tort exception if the act or omission occurred “in whole or in part” in the territory of the state exercising jurisdiction. Most nations that have codified the exception appear to require some act or omission in their territories, but it is not clear that these nations have done so from a sense of international legal obligation rather than from comity. Even if customary international law were properly read to preclude a nation from applying the territorial tort exception solely on the basis of death and damage within its territory, the application of JASTA to the 9/11 cases would still not violate international law, since the 9/11 attacks clearly involved tortious acts in the United States.

Another, more controversial, path would be to expand the FSIA’s terrorism exception, so that it covers state-sponsored terrorism even when the foreign state has not been designated by the State Department as a state-sponsor of terrorism, as is currently required under the FSIA. JASTA would not do this, but Curt and Jack discuss it at some length, so it is worth considering. They assert that the current exception “is almost certainly contrary to international law.” If this is true of the existing exception, then it would also be true of an expanded exception.

But I am not so sure that the terrorism exception violates customary international law. First, the United States is not alone in having adopted such an exception — Canada has done so too in Section 6.1 of its State Immunity Act. Second, to my knowledge, these exceptions have not provoked the sorts of widespread protests one might expect from other nations in the event of a clear violation of customary international law. Curt and Jack anticipate this point, explaining that “[t]he controversy has been muted, however, because the exception applies to only a few nations designated as bad actors by the executive branch.” This is true, but explaining away the absence of protests is not the same thing as having such protests as evidence of state practice. Third, Curt’s and Jack’s argument here necessarily depends on the choices they made at the outset about how to organize existing state practice. This is a situation in which the state practice is mixed — two states have such exceptions but most do not. Whether customary international law requires immunity for state-sponsored terrorism depends on whether one begins from a baseline of immunity (as Curt and Jack do) or from a baseline of non-immunity. To repeat what I said above, this is a choice and must be defended.

Of course, Curt and Jack are trying to make a policy argument based on reciprocity too. They write: “If the United States reduces the immunity it accords to other nations, it exposes itself to an equivalent reduction in its own immunity abroad.” But their reciprocity argument against JASTA depends on several propositions. First, it depends on the proposition that other states would view the immunity that the United States currently extends (and that JASTA would take away) as required by international law. If not, then they are already free to reduce the immunity they extend the United States, whether JASTA passes or not. Second, it depends on the proposition that other countries would read JASTA broadly to authorize exceptions to sovereign immunity in non-identical situations. Curt and Jack write: “It might appear that the United States has little to fear in lawsuits abroad for acts of terrorism akin to 9/11. But terrorism is often in the eye of the beholder, and reciprocity need not be precise.” A broad reading of JASTA is possible, but certainly not inevitable, and the United States would have strong arguments that its practice should be read more narrowly. Finally, Curt and Jack’s reciprocity argument depends on the proposition that international law influences the behavior of other states. I believe that to be true, but Jack has co-written an entire book disputing the proposition. See The Limits of International Law.

In the end, I am not certain whether Congress should pass JASTA. Much depends on how one weighs the benefits of providing legal redress for victims of terrorism against the impact on relations with countries like Saudi Arabia that currently cooperate with US counterterrorism efforts. But as a legal matter, the argument that JASTA would violate international law is far from clear.