Sosa and the Derivation of Customary International Law. By John O. McGinnis*

Sosa and the Derivation of Customary International Law By John O. McGinnis* My charge in this brief essay is to assess the implications of the recent Supreme Court decision in Sosa v. Alvarez-Machain 1 for customary international law ( CIL ) in American jurisprudence. Sosa is in an important sense sui generis, because there for the first time the Court gave substantial consideration to CIL in the context of the Alien Torts Statute ( ATS ). Nevertheless if one is forgiven a little latitude for extrapolation and speculation, it is interesting to analyze the Court s statements for their broader resonance about the derivation of CIL in American jurisprudence. After all, since making the Delphic declaration that international law was part of our law almost a century and quarter ago, the Supreme Court has made few direct pronouncements on the status of CIL or its method of derivation. Given the paucity of CIL analysis in any context, Sosa v. Alvarez--Machain s explicit discussion of the transformation of common law since the founding and its implicit recognition of changes in the nature of CIL may well turn out to be of substantial importance for the future of CIL within American law generally. Viewed at a high level of abstraction, Sosa represents an attempt to translate the reception of CIL in American jurisprudence from the Framers world to our own. In essence, this translation tries to make sure that our system receives only norms of comparable quality to those recognized in international norms at the time of the Framing with quality defined in terms of modern legal processes rather than the Framers processes. Ultimately we want norms to have * Stanford Clinton, Sr. Professor, Northwestern Law School. I am grateful for the comments of Eugene Kontorovich, Mark Movsesian, and Mike Ramsey. 1 542 U.S. 692 (2004). 1

indicia of high quality if they are to bypass our usual domestic process of bicameralism and presentment that themselves screen norms for quality. Within international law CIL has long had a mixture of positivist and natural law elements perhaps because of its own peculiar nature as universal law that nevertheless emerges from particular political divisions of the world. Sosa, however, suggests that within contemporary United States jurisprudence CIL must now take on a distinctively positivist cast because of our own system s peculiar nature where federal court s capacity to generate common law is circumscribed by our notions of democracy and our history of legal realism. This method of derivation occurs in the long shadow of Erie Railroad v. Tompkins. 2 Because law cannot any longer be thought to be a brooding ominipresence, it must be connected to sovereign power, in this case the widespread acceptance of an international norm as legal obligation through the acts of many sovereigns. 3 This analytic framework implies that sources, like that of publicists and international courts, are relevant for deriving CIL only insofar as they provide actual evidence of such sovereign acts. Part I of this essay very briefly summarizes Sosa. Part II suggests that many of the rationales Sosa provides for constraining the derivation of CIL in the context of ATS would apply more generally to deriving the content of CIL when used as a common law rule of decision or even to using CIL as an aid to statutory construction. Part III suggests that Sosa takes an astringently positivist view of CIL where overwhelming evidence of actual state practice must support a norm defined with substantial specificity for the norm to qualify as CIL in the context of American jurisprudence. Part IV concludes that while Sosa s constraints do not fully answer 2 304 U.S. 64 (1938). 3 For discussion and citations on this point, see infra note 47 and accompanying next. 2

modern critiques of any use of CIL without express endorsement of the political branches, they mute these criticisms by suggesting a modest scope for direct effect of norms of CIL. Indeed, it is possible that Sosa contains the offer of grand bargain about CIL: direct applicability of CIL within American jurisprudence is traded for a constrained methodology of derivation and consequent exclusion of much controversial content. I. The Case of Sosa v. Alvarez-Machain The case of Sosa v. Alvarez-Machain arose from a U.S government sponsored rendition of Dr. Alvarez-Machain from Mexico. The United States government indicted Alvarez -Machain for participating in the torture and murder of a DEA agent by a Mexican drug cartel. When the Mexican government failed to extradite Alvarez-Machain, the United States paid agents, including Sosa, to kidnap him in Mexico and bring him to the United States. Alvarez- Machain was tried and acquitted of the federal charges. He then brought a suit against Sosa under the ATS. The Court held that the ATS was jurisdictional in nature, but also that this jurisdiction enabled the courts to hear a set of claims under international law. 4 The Court held that recognition of international law norms under ATS was precluded with respect to claims with less definite content and acceptance among civilized nations than the historical paradigms familiar 5 when the ATS was enacted. The Court then detailed a variety of reasons for great caution for hearing any but well settled CIL norms under the ATS. These reasons centered on both the transformation of our understanding of the common law since the time of the Framing and ATS and the deference due to the political branches in implying a cause of action. 4 Sosa, supra note x, at. 5 Sosa, supra note x, at 732. 3

Applying this standard, the Court rejected the claims of Alvarez- Machain. Alvarez- Machain sought to claim that Sosa violated the international principle against arbitrary detention which he defined as officially sanctioned action exceeding positive authorization to detain under domestic law. 6 But the Court emphasized that Alvarez-Machain s unauthorized detention was relatively brief. It held that even if there were a general international law principle against detentions, to prevail Alvarez Machain would need to supply evidence that it applied specifically to brief detentions. 7 The Court thus applied its rule that an international norm must be recognized at the level of specificity at which it would be invoked rather inferred from principles that had been accepted at a higher level of abstraction. 8 It considered domestic laws on the subject from around the world and could find no such specific principle consistently recognized. The Court thus dismissed Alvarez-Machain s ATS claim. Most of the commentary about Sosa has revolved around its implications for the status of CIL in American jurisprudence. The essence of the standard view is that CIL binds the states and in some circumstances binds the federal government, at least unless countermanded by a controlling executive or legislative decision. 9 The revisionist view is that CIL binds domestically only when the political branches within their spheres of authority have acted to apply its norms domestically. 10 6 Id. at 736. 7 Id. at 736-737, 8 Id. 9 For a vigorous restatement of the standard position, Gerald L. Neuman, Sense and Nonsense About Customary International Law: A Response to Professors Bradley and Goldsmith, 66 FORDHAM L. REV. 371 (1997). 10 For the classic statement of the revisionist position, see Curtis A. Bradley & Jack L. Goldsmith, Customary International Law as Federal Common Law: A Critique of the Modern Position, 110 HARV. L. REV. 815 (1997); 4

In my view, despite the heroic attempts to enlist on Sosa on either side, the case cannot be said to settle the dispute between the standard view and the revisionists. As noted elsewhere in this volume, both the revisionist and standard accounts lead to doctrinal puzzles in the wider case law and these puzzles remain after Sosa. 11 Moreover, given Sosa s rather confusing account that how the ATS gives rise to substantive norms, it is not clear that Sosa addresses the issue of how CIL should be treated in the absence of any congressional expression of intent to apply it. Finally, it seems unlikely that an issue that divides the right and left blocs of the Court will be settled by a precedent that academics on each side have ably distinguished. In any event, given that this issue is exhaustively discussed elsewhere, 12 I leave it to one side. Sosa, however, may provide a more enduring framework for a federal court s derivation of customary international law. Whenever status CIL is given within American jurisprudence independent of express endorsement by the political branches, federal courts must decide whether a norm proffered as CIL will be applied. This methodological question nevertheless then has a practical bearing on the grander question of CIL s status. Insofar as CIL is derived in way that seems to limit the potentially broad discretion of federal judges and other unelected actors to determine international law norms and represents instead a limited set of norms that reflect judgments that more closely approximate democratic ones, the less opposition there will be to giving some autonomous status to CIL in American jurisprudence. On the other hand, an unconstrained method of deriving CIL that empowers natural views of justice and elite discretion 11 See Michael Ramsey, The U.S. Supreme Court and the Direct Application of Customary International Law, 1901-1945 12 Compare, e.g, Williams S. Dodge, Customary Law and the Question of Legitimacy, 120 HARV. L. REV. F. 19 (2007) with, Curtis A. Bradley, Jack L. Goldsmith and David Moore, Customary Law and The Continuing Relevance of Erie, 120 HARV. L. REV. 869 (2007). 5

in choosing among them is likely to lead to pressure to adopt the revisionist position in which it has no status without the express adoption of the political branches. II. The Scope of Sosa s CIL Concerns CIL has many potential applications in contexts other than the ATS. For instance, under some interpretations of the Paquete Habana, 13 CIL is part of our law, and can furnish a common law rule of decision without any express authorization from the political branches. 14 Under the venerable precedent of Charming Betsy, 15 CIL can be used as a principle to interpret ambiguous or vague provisions of a statute. 16 In such cases the content of CIL must be derived. Thus, a threshold question for the relevance of Sosa to CIL is whether its method for the derivation of the content of CIL would apply outside the context of the ATS. Two of the primary the rationales that Sosa provides for constraining CIL s derivation in the context of ATS apply to any use of CIL as federal common law. The first cautionary rationale is the changing conception of common law, including the common law that is CIL from a transcendental body of law that is not so much found or discovered as it is either made or created. 17 The second is the related change in the conception of the federal court s role in generating common law. 18 The Court says that in general federal courts are to await legislative guidance in making such law. 19 Within American jurisprudence common law, including CIL is 13 175 U.S. 677, 700 (1900). 14 As discussed in John O. McGinnis & Ilya Somin, Should International Law Be Part of Our Law, 59 Stan. L. Rev. 1175, 1188 (2007). 15 Murray v. Schooner Charming Betsy, 6 U.S. (2 Cranch) 64 ( 1804). 16 McGinnis & Somin, supra note x at 1192. 17 Sosa, supra note x, at 725. 18 Id. at 726. 19 Id. 6

no long generally understood as in any respect the discovery of immanent principles, much greater attention has to be given the process and institutions by which it formulated. Given that federal courts are unelected, they need to defer to the democratic branches, democracy being the legitimating process for the creation of norms that implicate state power. 20 Both of these rationales would seem applicable to the use of CIL as common law with effect on American law even outside of the ATS context. Indeed, it could be said the second rationale applies a fortiori, because, whatever limited guidance provided by ATS, the legislative branches have not furnished any general statutory guide to use of CIL as a rule of decision outside of this context. A nice question is whether these rationales would apply to the derivation of CIL for use as a rule of statutory construction under the Charming Betsy canon. Before using an international norm as a rule of construction, the federal court must first determine its content. This determination has the same difficulties as determining a rule for direct application. The rule is made rather than discovered and Congress has not provided any clear guidance in the area. Thus, it could be argued that Sosa s cautionary rationales apply in the context of construction as well. Some might counter that using international law as a rule of construction is less intrusive on Congress s prerogative and the democratic process in general, because Congress can of course override the Court s statutory construction. But Congress can override any use of CIL 20 For a discussion of why democracy is the legitimating feature of our system, see McGinis & Somin,1196-98 supra note x, For a discussion of why even constitutional norms are legitimated by a democratic process, albeit a supermajoritiarian one, see John O. McGinnis & Michael Rappaport, Originalism and the Good Constitution, 98 GEORGETOWN L. J. (2010) 7

and thus its ability does not distinguish it from the area where the Court had mandated caution in the use of custom. 21 Two of Sosa s other reasons for urging caution in deriving CIL seem to be more linked to the particular circumstances of the ATS in that they relate to providing private cause of actions under customary international law. First, the Court notes that even in the domestic context, it loath to infer private causes of action from substantive standards. It would be anomalous thus to be lax in the international sphere. 22 Second, permitting private causes of action here about matters that arise outside of the United States permits regulation of conduct in another country, thereby affecting our foreign policy. 23 In the context of furnishing a substantive rule of decision or rule of construction, the use of CIL within American jurisprudence may not require a private cause of action and that cause of action may not directly implicate a foreign nation. For instance, a litigant may press a cause of action under domestic law and yet argue that an international norm might be read to preclude the discretion that an official would otherwise enjoy. Thus, these additional reasons for caution in the context of ATS might suggest that Sosa s rules for CIL derivation do not apply unless CIL is used to furnish a private cause of action that has effects abroad. On the other hand, the first two rationales for caution may themselves be sufficient to require federal courts to derive CIL in the constrained matter that Sosa requires. As will be discussed below, the requirement that international norms reflect the actual widespread practices 21 For a general discussion of why it is not a complete answer to the democratic deficit of CIL to note that Congress can change the rule, see McGinnis & Somin at 1125. 22 Id. at 727. 23 Id. at 728. 8

of nation states, including democratic states, makes it more likely that the norms have some measure of democratic pedigree and limits the discretion of federal judges. Thus, the modern status of CIL as federal common law in the context of realist understanding of that common law may itself necessitate the methodology advanced by Sosa. Moreover, Sosa s additional reasons for caution in implying a cause of action may create additional screens through which international norms for ATS must pass, thus providing a particular function for these cautionary rationales peculiar to the ATS context. As Justice Stephen Breyer suggests in his Sosa concurrence, it should not be enough to show that that an ATS claim rests on a substantive rule of international law. 24 To be suitable to serve as the basis for an international law claim under ATS, a norm must rest on a procedural as well as substantive consensus, namely that the violation of international law can be universally prosecuted criminally or at least civilly. Sosa s additional concerns about using CIL as a private cause of action are captured by this additional hurdle which assures that other nations have consented to an international procedural mechanism. In contrast, the cautionary rationales that derive from the common law nature of CIL in American jurisprudence justify applying Sosa s constrained approach to deriving any substantive international law norms for use in American domestic jurisprudence regardless of context. III. Sosa s Recommended Methodology for Deriving International Law Assuming that Sosa s constrained approach is applicable to deriving CIL whenever it might be used a rule of decision, it represents the Court s endorsement of a relatively strict positivist 24 Sosa, supra note x, at 761-762 (Breyer, concurring) For discussion of the particular constraints that may implied before recognizing a private cause of action under ATS, see Eugene Kontorovich, Implementing Sosa v. Alvarez-Machain: What Piracy Reveals About the Limits of the Alien Tort Statute, 80 NOTRE DAME L. REV. 111(2004). 9

approach toward CIL rather than the looser approaches in the modern era. It requires evidence of actual state practice endorsing the international norm as legal obligation. It requires that this evidence be supplied at the level of specificity of the claimed international norm, rejecting inferences from acceptance of more diffuse and general principles. It implicitly rejects the notion that multilateral treaties that are not self-executing can serve by themselves as the basis for international norms. 25 To be sure, Sosa represents a single case. But it is important to note that its six-member majority was friendlier than the three-member dissenting bloc to apply international law. Changes in the Court s membership may well have whittled down that majority to five. 26 It thus seems unlikely that the current Court will be more permissive than the Sosa Court in screening the content of CIL norms that should be a given effect within American jurisprudence. To understand the possible significance of Sosa in this regard, it is necessary to discuss briefly the range of views on the nature of CIL in the modern era. An effective way to understand the range is to assess its poles, even if some scholars take a more middle-ground. Positivists or classicists in CIL occupy one of the poles. 27 They believe that CIL must be rooted in the widespread consensus of the actual practices of nation-states. 28 Only if nation states generally engage in a practice and do so from a sense of legal obligation, will that practice be 25 Sosa notes the existence of various multilateral treaties on the subject, but does not use them as evidence of a CIL obligation. Sosa, supra note x, at 734-735. 26 In their hearings both Chief Justice John Roberts and Justice Samuel Alito did not seem to be enthusiasts for international law. Cites Chief Justice Roberts replaced Chief Justice Rehnquist who was in dissent in Sosa. Justice Alito replaced Justice O Connor who was in the majority. 27 See, e.g., Arthur M. Weisburd, Customary International Law: The Problem of Treaties, 21 VAND. J. TRANS. L. 1, 32 (1988) (arguing for a more rigorous examination of evidence of state practice and opinio juris). 28 See RESTATEMENT (THIRD) OF THE FOREIGN RELATIONS LAW OF THE UNITED STATES 102 (requiring widespread acceptance of a rule for it be customary law). 10

deemed a rule of CIL. 29 The sense of legal obligation is called opinio juris and it too is measured objectively under the positivist conception. Under this view, the question for opinio juris is not whether the practice is morally right and should be observed out of a sense of legal obligation but whether it actually is undertaken from a sense of legal obligation. 30 This methodology for determining the rules CIL restricts its range. Partly for that reason, it may not be the prevalent view of contemporary scholars. 31 Many human rights norms would generally fail to qualify as custom in the this conception, because they rarely represent an actual consensus of the practices of states. 32 Moreover, as another essay in this volume shows, what might be regarded as the greatest twentieth century triumph of CIL providing the basis for the Nuremberg prosecution depends on a version of CIL that returns to its natural law roots. 33 Under a less positivist concept of international custom, some scholars embrace a methodology that permits substantial human rights norms to be encompassed within CIL. They relax the positivist standards in several ways that accomplish this. Instead of requiring that nation-states actually engage in a practice, they substitute statements by nation-states that give the norms verbal endorsement 34 --often at high levels of generality. These include resolutions of the General Assembly of the United Nations 35 and multilateral treaties. 36 29 Id. at comment e. 30 Id. at comment c. 31 See Patrick J. Kelly, The Twilight of International Law 40 VIR. J. INT L L. 449, 476 (2000). 32 See Anthea Elizabeth Roberts, Traditional and Modern Approaches to Customary International Law, 95 A.J.I.L. 757, 776 (2001). 33 See William S. Dodge, Customary International Law and the Supreme Court, 1945-2000, 34 Patrick McLain, Settling the Score with Saddam: Resolution 1441 and Parallel Justifications for the Use of Force Against Iraq, 13 DUKE J. COMP. & INT'L L. 233, 239 (2003). 35 CHRISTINE D. GRAY, INTERNATIONAL LAW AND THE USE OF FORCE 4 (2000). 36 Anthony D Amato, The Concept of Human Rights in International Law, 82 COLUM. L. REV. 1110, n. 98 (1982). 11

In short, some modern CIL has become less an inductive methodology in which custom is rooted in actual practices of states than a deductive methodology in which in it inferred from higher level, often natural law-like principles. 37 Under this conception, opinio juris at times becomes a normative concept, focusing not on whether nations in fact act out of a sense of legal obligation, but whether they should do so. 38 This cast of CIL doctrine necessarily gives more power to those making the inferences, such as publicists and international courts. The expansion of the consistent objector rule also makes nations actual practices less central to CIL, because nations can be seen as support CIL merely by failing to object. 39 This modern debate between deductive and inductive approaches has at least a faint echo of the debate recounted in this volume between Chief Justice Marshall and Justice Joseph Story in the Antelope, where Marshall took a positivist view and Story a natural law view. 40 Sosa s endorsement of a positivist, inductive paradigm at the expense of the more deductive one comes at three levels. First, the whole thrust of Sosa is to reduce uncertainty and constrain discretion in the derivation of CIL. 41 Because positivist CIL focuses on more objective factors, like hard evidence of actual state practice, it is the clearly the model to which Sosa tends. Second, Sosa requires claims of international norm to be a norm accepted by the civilized world and defined with substantial specificity. 42 Preventing inferences from norms 37 See Kelly, supra note x at 775-77.. 38 Id. 39 Id. at 508-510. 40 See David L. Sloss, Michael D. Ramsey, & William S. Dodge, International Law in the Supreme Court to 1860 41 See, e.g, Sosa at 73 ( Even the Restatement s limits are only the beginning of the enquiry... because it may be harder to say which policies corss that line with the certainty afforded by Blackstone s three common law offenses. 42 Sosa, supra note x, at 734-735. 12

accepted at high level of generality gives less play for consideration of the reasonableness of the rule or the inferences of publicists or international courts from general principles. Finally, in evaluating the claims of Alvarez-Machain, Sosa takes evidentiary positions that are much more in keeping with a stringently positivist view. 43 It looks for hard evidence that nations have generally accepted that domestic law must authorize even short detentions, because that is the level of specificity at which Alvarez-Machain is making his claim. 44 It rejects the notion that such a claim can be based on non-self-executing multilateral human rights treaties or, at least by implication, expressions of support for international norms within international institutions the kind of inference sometimes found in modern CIL. 45 It specifically contrasts the aspirations for such a principle of justice with the lack of evidence for such a principle of positive law, making clearly that CIL cannot be based on moral reasoning or inferences. 46 This approach to CIL derivation reflects the movement to positivism contained in Erie. If federal courts are not to make CIL a brooding omnipresence in the sky, they need to ground it in sovereign acts. A positivist view of CIL can achieve this because CIL is supposed to reflect the widespread if not universal decision to adopt a norm of international law as binding law. 47 It thus follows that the legal sources that are relevant to determining CIL are those that directly help us determine the sovereign acts of nation states that made such adoptions. 43 One possible counterargument is that while the Court signaled the need for great caution and rigor in deriving CIL norms, it also cited approvingly Filartiga v. Pena-Irala, 630 F. 2d. 876, 884 n. 15 (2d Cir. 1980), which was less rigorous and cautious. But in this respect I agree with Professor Bradley, Goldmith and Moore who argue that these citations must bear less weight than the Court s own treatment of controversial sources of CIL, which... was significantly restrained. Bradley, Goldsmith & Moore, supra note x, at 901. 44 Id. at 737 (considering Alvarez Machine s evidence of arbitrary nation, but finding that insufficient number of nations is at too high a level of generality to support norm against brief detentions). 45 See Curtis Bradley, International Delegations, The Structural Constitution and Non-Self-Execution, 55 Stan. L. Rev. 1557, 1581 n. 117 (2005). 46 Id. at 728. 47 See Ramsey, supra note x, at y ( suggesting that after Erie international law can be conceptualized as coming from sovereign authority, or rather the common consent of multiple sovereigns. ) 13

Legal realism has also played a role in this construction of CIL. Sophisticated legal realism, of course, suggests not that judges and other legal actors make all decisions according to politics but that politics informs their use of discretion and resolution of ambiguity. The realist concern about judicial discretion provides another reason to try to ground CIL in specific principles reflected in the actual acts of sovereigns rather than inferences by publicists or others from higher level principles. 48 Thus, given Erie and the rise of legal realism, it is not surprising that Sosa takes a more constrained view of the sources and method for deriving a positive CIL than the Paquete Habana did more than a century ago. 49 IV. Normative Analysis Some scholars have suggested that CIL should not be given any binding effect in the jurisprudence of the United States because it is of low quality. 50 Its low quality stems from its democratic deficit that is not redeemed by any compensating features. In this section, I evaluate the extent to which to Sosa s constrained version of the classical CIL addresses these criticisms. A constrained version of positivist CIL helps temper concerns about a democratic deficit. One of substantial concerns about democratic deficit was the role of unelected publicists or international courts in making inferences about the content of CIL. But Sosa s theory makes clear that publicists theories are useful only if the provide hard evidence of a norm from actual state practice. Moreover, if CIL must be based on the actual acts of states and evaluated at the level of specificity for which the claim is made there is much less room for inferences about the 48 There can be no doubt that publicists may have distinctive political views unrepresentative of their nations. See John O. McGinnis e al., The Patterns and Implications of Political Contributions of Elite Law School Faculty, 93 GEORGETOWN L. J. 1167, 1883 (2005) (showing that international law professors contribute to Democratic candidates rather than Republicans by a margin of 5 to one). 49 As discussed in David Bederman, Customary International Law and the Court, 1860-1900 50 See, e.g, McGinnis & Somin, supra note x, at 1179-1180. 14

content of CIL. Thus, Sosa s inductive process constrains the power of unrepresentative elites over its precise content reduces the democratic deficit. Second, Sosa s rejection of using non-self executing multilateral treaties and its interest in finding evidence of CIL at the level of domestic state practice helps address another element contributing to an important democratic deficit the danger that CIL will be based on the cheap talk of agreements that states are willing to sign but whose content they are not willing to apply in their domestic legal systems. 51 Finally, Sosa demands evidence that the great majority of nations in the world, including democratic nations, would give legal effect to the norm at issue. Thus, a strict positivist construction of CIL would temper the democratic deficit, because the consensus of many nations would likely include a wide number that are democratic. Nevertheless, this reading of Sosa does not completely alleviate the concerns of those who complain of democratic deficit of CIL. First, the best notions of democracy include a notion of subsidiarity. Yet some aspects of modern CIL, particularly human rights norms, concern matters that do not have substantial externalities from one nation to another. In the absence of substantial externalities, it does not advance democratic principles informed by subsidiarity to impose international law norms on a democratic nation like the United States even if these norms enjoy widespread support in other democratic nations. 52 As the people most affected the citizens of each nation are in the best position to make determinations about norms that have effect only in their nation. Moreover, the diversity in rights norms among different democratic nations is 51 See McGinnis & Somin at 1206. 52 I have argued elsewhere that the democratic deficit is problem in this respect even with human rights law, see John O. McGinnis & Ilya Somin, Democracy and International Human Rights Law, 84 NOTRE DAME L. REV. 1739 (2009). 15

beneficial, because nations can learn from one another by analyzing the effects of such norms and, to at least a limited extent, citizens can choose from different bundles of norms by decisions about where to live. Second, because positivist international law requires widespread consensus among states, once formulated it is difficult to change because it would appear to require a new consensus to create a new norm. 53 Even if all states participating in the formulation of international law were democratic it might fail to represent contemporary sentiment, as opposed to past democratic sentiment. The consensus requirement of international law could on occasion lock in norms even if they are suboptimal. 54 The problem is exacerbated in an age of rapid technological change and, according to some, accelerating change. 55 Because CIL arose at time when technological and social change was relatively slow, its rules once in place were unlikely to become anachronistic. But if the nature of the world s social problems changes faster today, the dead hand problem becomes more acute. One might argue that other doctrines may address this problem. If CIL must yield to controlling executive authority, the President within his sphere of authority and Congress within its sphere can set aside international norms that are outdated. Nevertheless, this doctrine does not provide a complete answer to the dead hand of CIL, because CIL would still be the default rule. Congress, in particular, faces substantial legislative inertia in changing social norms. 53 Van Hoof, supra note x at 114. 54 This can be a general problem with norms that rely on entrenched customs. See Eric A. Posner, Law, Economics, and Inefficient Norms, 144 U. PA. L. REV. 1697, 1712 (1996. 55 See RAY KURZWEIL, THE SINGULARITY IS NEAR 10-20 (2005) (arguing that technology is changing at an ever accelerating rate). 16

Finally and perhaps most importantly, the derivation of CIL remains a more complex and uncertain enterprise than discerning norms in a legal code or canonical text. Sosa s test for the content of CIL may not succeed in forcing future judges to be similarly constrained. Substantive due process in United States constitutional law furnishes a useful analogy. In Washington v. Glucksberg, 56 the Court tried to cabin the derivation of substantive process. The Glucksberg Court required the identification of a fundamental right "objectively, deeply rooted in this Nation's history and tradition," as well as a "careful description of the asserted fundamental liberty interest." 57 The similarity between the Glucksberg standard for deriving fundamental rights and the Sosa standard for deriving CIL is striking. Sosa s requirement that international law norms represent a consensus of the actual practices of the civilized world, like Glucksberg s requirement of objective evidence of deeply rooted traditions, helps make sure that norms have objective roots in democratic sentiment. Sosa s requirement of specificity, like Glucksberg s requirement of careful description, attempts to cabin the discretion of judges. Yet less than ten years after Glucksberg, the Court in Lawrence v. Texas announced a right to same-sex sexual conduct under the due process clause when that right could not be derived by Glucksberg s methodology. 58 Thus, the ultimate question about Sosa s structure for deriving CIL may be its staying power. The experience with substantive due process suggests judges have difficulty in respecting the constraints of their own creation when these interfere with the achievement of their own notions of natural justice. Thus, the old tension between natural law and positivist roots of CIL 56 521 U.S. 702 (1997). 57 Id. at 721. 58 See Lawrence v. Texas, 539 558 (2003). For a discussion of this point, see Nelson Lund & John O. McGinnis, Lawrence v. Texas and Judicial Hubris, 102 MICH. L. REV. 1555 (2004). 17

jurisprudence may yet reemerge in the context of U.S. jurisprudence. The Court will surely have future opportunities to demonstrate its adherence (or lack thereof) to the Sosa framework, because a number of lower courts have found international norms under ATS with an expansive methodology that appears incompatible with Sosa. Conclusion Sosa v. Alvarez-Machain may have important implications for deriving CIL even outside the context of ATS, because it recognizes the need for constraint on its content given its status as common law and the modern realist understanding of common law. If the Court continues on the path set by Sosa a condition admittedly not free from doubt within American jurisprudence CIL would acquire a somewhat austere aspect. Normatively this development would be welcome, because it would refocus the decisions about the reception of controversial international norms from the judiciary to the more democratic branches. It would also temper the importance of the fierce debate about the status of CIL in American jurisprudence, because the scope of CIL that would be imported even under the standard position would be modest and would generally reflect only those specific norms that were given effect by the great majority of nations, including democratic nations, around the world. 18