¹ Frishman, Olga & Benvenisti, Eyal, National Courts and Interpretative Approaches to International Law, in The Interpretation of International Law by Domestic Courts: Uniformity, Diversity, Convergence 317, 317 (Aust, Helmut Philipp & Nolte, Georg eds., 2016)Google Scholar [hereinafter Interpretation of International Law] (criticizing the “convergence thesis” on normative and pragmatic grounds).

² George Nolte, Introduction, in Interpretation of International Law, supra note 1, at 1 (noting that “much has been written about the status and the role of international law in particular domestic legal systems and about the practice of courts from different jurisdictions regarding the interpretation of particular treaties” as well as on “the relationship between international (treaty) law and national law in general”).

³ See, e.g., Bello, Emmanuel G., How Advantageous Is the Use of Comparative Law in Public International Law, 66 Revue de Droit International, De Sciences Diplomatiques Et Politiques 77 (1988)Google Scholar; Stein, Eric, International Law in Internal Law: Toward Internationalization of Central-Eastern European Constitutions?, 88 AJIL 427 (1994)Google Scholar; Stein, Eric, Frowein, Jochen A., Danilenko, Gennady M. & Iwasawa, Yuji, International Law in Domestic Legal Orders: A Comparative Perspective, 91 ASIL Proc. 289 (1997)Google Scholar. For an overview, see Roberts, Anthea, Stephan, Paul B., Verdier, Pierre-Hugues & Versteeg, Mila, Comparative International Law: Framing the Field, 109 AJIL 467, 468, n.7 (2015)Google Scholar.

⁴ The 2015 Comparative International Law special issue of AJIL may serve as both evidence of and catalyst for this trend. The issue editors provisionally defined comparative international law as “identifying, analyzing, and explaining similarities and differences in how actors in different legal systems understand, interpret, apply, and approach international law.” See Roberts, Stephan, Verdier & Versteeg, supra note 3, at 469. They further claim that this undertaking has gained momentum because of “the growing globalization of legal practice, the increased penetration of international law into the domestic realm, the rising transnational flow of law students, the greater accessibility of diverse national sources through electronic databases, and the movement towards an era of multipolar power.” Id. at 468–69.

⁵ Legislatures consent to treaty ratification (or not), attach reservations to treaties, and pass implementing legislation. See Cope, Kevin L. & Movassagh, Hooman, Comparative International Law in National Legislatures, in Comparative International Law (Roberts, Anthea, Stephan, Paul B., Verdier, Pierre-Hugues & Versteeg, Mila eds., 2017)Google Scholar. Executives and parliaments routinely interpret international agreements in the course of foreign relations, and judges frequently defer to these interpretations. See Julian Arato, Deference to the Executive: The US Debate in Global Perspective, in Interpretation of International Law, supra note 1, at 199.

⁶ André Nollkaemper, Grounds for the Application of International Rules of Interpretation in National Courts, in Interpretation of International Law, supra note 1, at 34, 35.

⁷ See, e.g., Roberts, Anthea, Comparative International Law: The Role of National Courts in Creating and Enforcing International Law, 60 Int'l & Comp. L. Q. 57 (2011)Google Scholar. But see Theresa Reinold, Diffusion Theories and the Interpretative Approaches of Domestic Courts, in Interpretation of International Law, supra note 1, at 267, 287 (theorizing that judicial decision-making around the world is unlikely to be characterized by convergence alone and that it “would be naïve to assume that domestic judges’ interpretations of international law are not colored by local, national, or regional norms”). Studies suggest that national courts increasingly communicate with one another across borders, heightening the importance of their decisions. See, e.g., Slaughter, Anne-Marie, A Global Community of Courts, 44 Harv. Int'l L.J. 191 (2003)Google Scholar; Antonios Tzanakopoulos, Judicial Dialogue as a Means of Interpretation, in Interpretation of International Law 198; Benvenisti, Eyal, Reclaiming Democracy: The Strategic Uses of Foreign and International Law by National Courts, 102 AJIL 241, 251 (2008)Google Scholar.

⁸ Vienna Convention on the Law of Treaties, Arts. 31–32, opened for signature May 23, 1969, 1155 UNTS 331, at http://legal.un.org/ilc/texts/instruments/english/conventions/1_1_1969.pdf [hereinafter VCLT].

⁹ Michael Waibel, Principles of Treaty Interpretation: Developed for and Applied by National Courts?, in Interpretation of International Law, supra note 1, at 9, 22 (exploring whether domestic courts are legally bound to use the VCLT principles and concluding that the VCLT imposes an obligation “of result only” but “does not require state organs such as national courts to use a particular interpretive methodology”); Nollkaemper, supra note 6, at 37–48 (suggesting that courts are not necessarily required to use the VCLT rules, but suggesting reasons it might be justified for them to do so).

¹⁰ See Interpretation of International Law, supra note 1, at pt. II.

¹¹ See id., pt. III.

¹² Dire Tladi, Interpretation of Treaties in an International Law-Friendly Framework: The Case of South Africa, in Interpretation of International Law, supra note 1, at 136, 151 (noting that it is “the major conclusion of the chapter” that “South African courts have generally not referred to the Vienna rules, and where the courts have referred to the Vienna rules, it has been superficial”); id. at 140 (noting that use of the VCLT rules “facilitates consistent interpretation of treaty rules and the search for the objective meaning of the treaty, which is arguably an expectation of states when they conclude the treaty”); Arato, supra note 5, at 201 (clarifying that his contribution starts “from the presumption that a treaty has one correct interpretation, and that the Vienna Rules provide the authoritative guide for accessing its true meaning”).

¹³ Frishman & Benvenisti, supra note 1, at 322–28 (criticizing the “convergence thesis” on normative and pragmatic grounds); Helmut Philipp Aust, Between Universal Aspiration and Local Application: Concluding Observations, in Interpretation of International Law, supra note 1, at 333.

¹⁴ Cf. Leiter, Brian, Positivism, Formalism, Realism, 99 Colum. L. Rev. 1138, 1145 (1999)CrossRefGoogle Scholar (reviewing Anthony Sebok, Legal Positivism in American Jurisprudence (1998), which describes the elements of legal formalism).

¹⁵ John Henry Merryman & Rogelio Pérez-Perdomo, The Civil Law Tradition: An Introduction to the Legal Systems of Europe and Latin America 47 (3d ed. 2007). But see Lasser, Mitchel De S.-O.-l'E., Comparative Law and Comparative Literature: A Project in Progress, 1997 Utah L. Rev. 471, 474 (1997)Google Scholar (arguing that Merryman's “caricature of the French legal system needs some correction”).

¹⁶ Merryman & Pérez-Perdomo, supra note 15, at 43.

¹⁷ Brian Leiter, American Legal Realism, in The Blackwell Guide to Philosophy of Law and Legal Theory 50 (Edmundson, W. & Golding, M. eds., 2005)Google Scholar.

¹⁸ Alejandro Rodiles, Re-contextualizing the Pro Persona Principle: Concluding Remarks, in Interpretation of International Law, supra note 1, at 173 (claiming that some Latin American courts’ “domestic vocabulary “usually corresponds to the rules codified in the VCLT” and that “pro persona is, as such, compatible with object and purpose”).

¹⁹ See Christian Djeffal, Dynamic and Evolutive Interpretation of the ECHR by Domestic Courts? An Inquiry into the Judicial Architecture of Europe, in Interpretation of International Law, supra note 1.

²⁰ The VCLT assigns a secondary role to the travaux preparatoires, allowing its use “in order to confirm the meaning resulting from the application of article 31, or to determine the meaning when the interpretation according to article 31: (a) leaves the meaning ambiguous or obscure; or (b) leads to a result which is manifestly absurd or unreasonable.” See VCLT, supra note 8, Art. 32. But see generally Mortenson, Julian Davis, The Travaux of Travaux: Is the Vienna Convention Hostile to Drafting History?, 107 AJIL 780, 781 (2013)Google Scholar (arguing that the conventional wisdom that the VCLT gives drafting history a subsidiary role “cannot be reconciled with the agreement actually reached”).

²¹ See, e.g., Kevin L. Cope & James D. Morrow, Alliance-Forming in International Convention Negotiations: The International Criminal Court (working paper on file with authors, 2017); Kevin L. Cope, Charles Crabtree & James D. Morrow, working paper (2017, on file with authors).

²² See also Anthony Aust, Modern Treaty Law and Practice 205 (2013).

²³ Frishman & Benvenisti, supra note 1, at 326 (observing that “‘constructive ambiguity’ is key to reaching agreement”); see generally Barbara Koremenos, The Continent of International Law: Explaining Agreement Design (2016).

²⁴ See Aust, Modern Treaty Law and Practice, supra note 22, at 230 (noting that the adage “the interpretation of documents is to some extent an art, not an exact science” is “especially true for treaties, which are the product of negotiations leading to compromises to reconcile, often wide, differences”).

²⁵ Nolte, supra note 2, at 3 (“Very often, however, domestic courts do not emphasize that a treaty [provision] must be given an autonomous meaning, and they do not refer to Articles 31 and 32 of the Vienna Convention when interpreting treaties. They rather ‘take colour’ from their ‘national legal culture’ when interpreting and applying a treaty … .”); Waibel, supra note 9, at 25 (observing that “the U.S. Supreme Court until today has never relied expressly on the VCLT in a treaty interpretation case”); id. at 23 (observing that the English courts regard the VCLT principles as an “appropriate framework for the interpretation of treaties” but that they “reserve themselves considerable wiggle room on whether or not to use the VCLT principles of interpretation in specific cases, not unlike their US counterparts”); Tladi, supra note 12, at 136, 151 (noting that it is “the major conclusion of the chapter” that “South African courts have generally not referred to the Vienna rules, and where the courts have referred to the Vienna rules, it has been superficial”); Rodiles, supra note 18, at 173 (noting that the Colombian Constitutional Court and the Mexican Supreme Court do not refer to the VLCT, but that their “domestic vocabulary” “usually corresponds to the rules codified in the VCLT—pro persona is, as such, compatible with object and purpose”); Eirik Bjorge, ‘Contractual’ and ‘Statutory’ Treaty Interpretation in Domestic Courts? Convergence Around the Vienna Rules, in Interpretation of International Law, supra note 1, at 49, 58 (the French “Cour de Cassation only rarely cites and relies explicitly upon the Vienna rules”); Yukiko Takashiba, Gingerly Walking the VCLT Frontier? Reflections from a Survey on the Interpretative Approach of the Japanese Courts to Treaties, in Interpretation of International Law, supra note 1, at 218, 219 (finding that “a great majority of decisions draw conclusions without reference to the VCLT canon” and that “[l]imited references to the VCLT rules are made at the level of district or high courts but they are in response to the plaintiffs’ reliance thereon, often with little elaboration beyond reciting the rules”); Vik Kanwar, Treaty Interpretation in Indian Courts: Adherence, Coherence, and Convergence, in Interpretation of International Law, supra note 1, at 239, 246 (finding that Indian courts do not usually explicitly rely on the VCLT rules, with the exception of tax cases involving “Double Taxation Avoidance Agreements”).

²⁶ See, e.g., McGowan, Miranda, Do as I Do, Not as I Say: An Empirical Investigation of Justice Scalia's Ordinary Meaning Method of Statutory Interpretation, 78 Miss. L.J. 129 (2008)Google Scholar (analyzing the relationship between Justice Scalia's statutory interpretive methods and his authored case results).

²⁷ See Winkler, Adam, Fatal in Theory and Strict in Fact: An Empirical Analysis of Strict Scrutiny in the Federal Courts, 59 Vand. L. Rev. 793 (2006)Google Scholar.

²⁸ Frishman & Benvenisti, supra note 1, at 322–28.

²⁹ For a primer, see Linos, Katerina, How to Select and Develop International Law Case Studies: Lessons from Comparative Law and Politics, 109 AJIL 475 (2015)Google Scholar; see also Ran Hirschl, Comparative Matters: The Renaissance of Comparative Constitutional Law 224–81 (2014); Hirschl, Ran, The Question of Case Selection in Comparative Constitutional Law, 53 Am. J. Comp. L. 125 (2005)Google Scholar.

³⁰ VCLT, supra note 8.

³¹ See generally Koremenos, supra note 23.