The migration of constitutional ideas is an interpretative and legislative act of borrowing ele- ments belonging to given constitutional traditions and importing them into a different legal system. Constitutional law indicates a body of national law setting up fundamental norms and mechanisms of power control for the protection of the rights of the citizenry.10 The gist of consti- tutional law is to subject the exercise of governmental powers to the limitations of a higher law.
The migration of constitutional ideas is related to—but differs from—constitutionalism, in that the former implies a distance and/or invisible boundary between the source (i.e., the constitution), and the destination (in casu international investment law and arbitration).
Rather, constitutionalism is a conceptual movement or doctrinal project—some contend a phenomenon—which proposes the constitutionalization of a number of different areas of law,11 conceiving public law as a field of knowledge that transcends the dichotomy between the national and the international. Constitutionalization indicates “the attempt to subject all governmental action within a designated field to the structures, processes, principles and values of a ‘constitution’ … Since governmental power is now being channelled through
times by the European Court of Justice in Luxembourg, and by the European Court of Human Rights in Strasbourg.’).
8. The method by which arbitral tribunals have sought to identify a norm as one of customary international law encompasses consideration of both state practice and opinio juris.
9. Evelyn Ellis (ed), The Principle of Proportionality in the Laws of Europe (Hart Publishing 1999).
10. Scott Gordon, Controlling the State: Constitutionalism from Ancient Athens to Today (Harvard University Press 1999) 4.
11. Norman Dorsen, Michel Rosenfeld, András Sajó and Susanne Baer, Comparative Constitutionalism. Cases and Materials (2nd ed., West 2010).
regional, supranational and international agencies, constitutionalization … [aims at] subject- ing the exercise of all types of public power … to the discipline of constitutional procedures and norms.”12 The constitutionalization of different areas of law, ranging from public interna- tional law,13 to EU law,14 international trade law,15 and international investment law16—scholars argue—promote their humanization, suggest the idea of a scale of higher values, and thus potentially contribute to the legitimacy of the system.17 Whether or not the constitutionaliza- tion of these areas of law has taken place is subject to debate.
For the limited purpose of this study, suffice it to say that constitutional law principles can (and have) influenced other areas of the law. In particular, constitutional law has played a pivotal role in the making of international law. For instance, the provisions against indirect expropriation in a number of international investment treaties—most notably the U.S. Model BIT—derive from U.S. constitutional law, specifically, the Penn Central test, articulated by the U.S. Supreme Court.18 In parallel, as the U.S. Model BIT is often used as a template by a num- ber of countries in their investment for treaty negotiations, the lex Americana has become the gold standard in the area.19 This process has not been uncontroversial or uncontested. Some commentators have argued that the extensive protection granted to investors’ (property) rights amounts to an extraterritorial application of the Fifth Amendment of the U.S. Constitution,20 or an expression of the “Americanization” of international law.21
12. Martin Loughlin, ‘What is constitutionalization?’ (2009) 3 International Journal of Constitutional Law and Politics 1.
13. Jan Klabbers, Anne Peters and Geir Ulfstein, The Constitutionalization of International Law (Oxford University Press 2009) (examining the questions as to whether, and if so to what extent, the international legal system has constitutional features comparable to what we find in national law); Nicholas Tsagourias (ed), Transnational Constitutionalism: International and European Models (Cambridge University Press 2007);
Ronald St. John MacDonald and Douglas M. Johnston (eds), Towards World Constitutionalism: Issues in the Legal Ordering of the World Community (Martinus Nijhoff 2005); Erika De Wet, ‘The constitutionalization of public international law’ in Michel Rosenfeld and András Sajó (eds), Oxford Handbook of Comparative Constitutional Law (Oxford University Press 2012) ch 58; Jürgen Habermas, ‘The constitutionalization of inter- national law and the legitimation problems of a constitution for world society’ (2008) 15 Constellations 444.
14. Christiaan Timmermans, ‘The constitutionalization of the European Union’ (2002) 21 Yearbook of European Law 1.
15. Deborah Z. Cass, ‘The “constitutionalization” of international trade law: judicial norm generation as the engine of constitutional development in international trade’ (2001) 12 European Journal of International Law 39; Deborah Z. Cass, The Constitutionalization of the World Trade Organization: Legitimacy, Democracy, and Community in the International Trading System (Oxford University Press 2005); Christian Joerges and Ernst-Ulrich Petersmann (eds), Constitutionalism, Multilevel Trade Governance and International Economic Law (Hart Publishing 2011).
16. Peter Behrens, ‘Towards the constitutionalization of international investment protection’ (2007) 45 Archiv des Vửlkerrechts 153.
17. Mattias Kumm, ‘The legitimacy of international law: a constitutionalist framework of analysis’ (2004) 15(5) European Journal of International Law 907.
18. Penn Central Transportation Co. v New York City, 438 U.S. 104, 124 (1978).
19. José E. Alvarez, ‘The evolving BIT’ in I. A. Laird and T. Weiler (eds), Investment Treaty Arbitration and International Law (Juris 2010) 12–13.
20. David Schneiderman, ‘NAFTA’s takings rule: American constitutionalism comes to Canada’ (1996) 46 University of Toronto Law Journal 499; Gregory M. Starner, ‘Note, Taking a constitutional look: NAFTA Chapter 11 as an extension of Member States’ constitutional protection of property’ (2002) 33 Law & Policy of International Business 405.
21. On the Americanization of international arbitration, see Susan L. Karamanian, ‘Overstating the
‘Americanization’ of international arbitration: lessons from ICSID’ (2003) 19 Ohio State Journal on Dispute Resolution 5. On the Americanization of international law, see Ugo Mattei, ‘Globalization and empire: a
At the adjudicative level, constitutional ideas have migrated across boundaries,22 contribut- ing to the phenomenon of “judicial globalization”23 and the cross-pollination of different legal cultures. International courts and tribunals as well as constitutional courts around the world have increasingly “cross-judged”—that is, cited and or relied upon each other’s opinions—with varied success,24 determining a judicial dialogue at both horizontal and vertical levels. At the horizontal level, the migration of constitutional ideas allows international courts and tribunals to combat fragmentation across the various regimes of international law. In parallel, national courts do consider foreign viewpoints in addressing analogous issues.25 In a vertical or hier- archical sense, national courts and tribunals in common law jurisdictions follow the rule of stare decisis; analogously in civil law jurisdictions, courts do regard the previous decisions of superior courts, albeit not formally bound by the latter. At the vertical level, the migration of constitutional ideas from constitutional law to the international sphere allows a dialogue between national constitutional courts on the one hand and international courts and tribunals on the other.26 The internationalization of constitutional law has also given rise to a common lexicon which nourishes the emergence of commonalities27 and fosters the circular migration of constitutional ideas from constitutional courts to international fora and then back to con- stitutional courts.28 The migration of constitutional ideas to international law is not unbound;
the duty to bring national law into conformity with international law is a well settled part of customary law29 and this is confirmed by consistent jurisprudence.30 Reliance on national con- stitutional provisions does not justify a violation of public international law.31
The migration of constitutional ideas constitutes a signum temporis due to the coexistence of different, at times overlapping and/or diverging legal systems (legal pluralism).32 Law—once the exclusive domain of states—has become a polycentric phenomenon becoming the terrain
theory of imperial law: a study on U.S. hegemony and the latin resistance’ (2003) 10 Indiana Journal of Global Legal Studies 383 (noting that ‘in the age of colonialism political battles for international power were mostly carried out with an open use of force and political violence … , whereas in the age of globalization and of economic Empire, political violence has been transformed into legal violence’).
22. Sujit Choudry, ‘Migration as the new metaphor in comparative constitutional law’ in Sujit Choudry (ed), The Migration of Constitutional Ideas (Cambridge University Press 2006).
23. Anne-Marie Slaughter, ‘Judicial globalization’ (2000) 40 Virginia Journal of International Law 1103.
24. See e.g., Symposium, ‘Constitutional Borrowing’ (2003) 1 International Journal Constitutional Law 177.
25. Ruti Teitel, ‘Comparative constitutional law in a global age’ (2004) 117 Harvard Law Review 2570.
26. In certain cases, the migration of constitutional ideas can also give rise to the coalescence of general principles of international law and/or customary law (as evidence of state practice), thus contributing to the development of international law.
27. See e.g., David Feldman, ‘Modalities of internationalisation in constitutional law’ (2006) 18(1) European Review of Public Law 131.
28. Eyal Benvenisti, ‘Reclaiming democracy: the strategic uses of foreign and international law by national courts’ (2008) 102 American Journal of International Law 241; Eyal Benvenisti and George W Downs,
‘National courts, domestic democracy, and the evolution of international law’ (2009) 20 European Journal of International Law 59.
29. Ian Brownlie, Principles of Public International Law (7th ed., Oxford University Press 2008) 35.
30. See e.g., Polish Nationals in Danzig (1931) PCIJ Ser. A/B (no. 44) 24.
31. Vienna Convention on the Law of Treaties (VCLT) of 23 May 1969, in force 27 January 1980, UN Treaty Series vol. 1155, p 331, art 27.
32. See e.g., Günther Teubner, ‘“Global Bukovina”: legal pluralism in the world society’ in Günther Teubner (ed), Global Law Without a State (Dartmouth Publishing 1997); Michel Rosenfeld, ‘Rethinking constitu- tional ordering in an era of legal and ideological pluralism’ (2008) 6 International Journal of Constitutional Law 415–455.
of competition among multiple regulatory entities at national, regional, and international levels.33 Globalization has also eroded traditional boundaries, increasing the availability of information and access to the same. The adoption of communal judicial approaches is mainly motivated by functional reasons; especially when adjudicators are faced with difficult cases, resorting to other cases may provide them with useful examples and reinforce their perceived legitimacy. In addition, authors have pointed out the necessity of looking outside the constitu- tion as a tool for reassessing it, and adjusting it to evolving circumstances.34 The influence of borrowing goes beyond the specific case, influencing the culture of the importing system,35 and determining gravitation toward certain models which exert dominant influence. Reverse constitutional borrowing—that is, absorbing the experience of other systems after their bor- rowing of constitutional concepts—is theoretically possible, albeit rare.36 For instance, report- edly a few countries changed their constitutions to make them compatible with their bilateral investment treaties requiring adequate compensation in case of expropriation.
As the migration of constitutional ideas is in essence a comparative law endeavor, meth- odological concerns have long been the stock in trade of this process.37 Comparative law faces deep methodological challenges,38 concerning, inter alia, “the proper terms, categories, scales, methods, and data to be used in comparison,”39 and recent literature has highlighted the existence of various methodologies.40 More specifically, with regard to the migration of
33. On the emergence of private actors, see e.g., Claire Cutler, Private Power and Global Authority: Transnational Merchant Law in the Global Economy (Cambridge University Press 2003).
34. Ernest A. Young, ‘The constitution outside the constitution’ (2007) 117 Yale Law Journal 408 473.
35. See Colin B. Picker, ‘International investment law: some legal cultural insights’ in Leon Trakman and Nicola Ranieri (eds), Regionalism in International Investment Law (Oxford University Press 2013) 27–58;
Andrea K. Bjorklund, ‘The emerging civilization of investment arbitration’ (2009) 113 Penn State Law Review 1269; Debra P. Steger, ‘The culture of the WTO: why it needs to change’ (2007) 10 Journal of International and Economic Law 483–95; Galit A. Sarfaty, Values in Translation: Human Rights and the Culture of the World Bank (Stanford University Press 2012); Galit A. Sarfaty, ‘Why culture matters in international institutions: the marginality of human rights at the World Bank’ (2009) 103 American Journal of International Law 647.
36. David S. Law and Mila Versteeg ‘The declining influence of the US Constitution’ (2012) 87 New York University Law Review 762, 767, 852 (mentioning the views of a few scholars that ‘[t] he reluctance of the U.S.
Supreme Court to … participat[e] in an ongoing “transnational judicial dialogue” is supposedly diminishing the global appeal and influence of American constitutional jurisprudence.’).
37. Peer Zumbansen, ‘Transnational Comparisons: Theory and Practice of Comparative Law as a Critique of Global Governance’ (2012) Osgoode Hall Law School Comparative Research in Law & Political Economy Research Paper Series Research Paper 1/2012, 11, <http://digitalcommons.osgoode.yorku.ca/cgi/viewcontent.
cgi?article=1003&context=clpe> (noting that ‘[j] ust as comparative law in general, constitutional compari- sons, too, are still plagued by a great degree of methodological uncertainty and theoretical indeterminacy.’).
38. Annelise Riles, ‘Wigmore’s treasure box: comparative law in the era of information’ (1999) 40 Harvard International Law Journal 221, 224 (highlighting that a ‘collective crisis of methodological confidence is some- thing of a defining genre of comparative legal scholarship, as each commentator outdoes the next with dire critiques of the field and timid solutions for reconfiguration’).
39. Annelise Riles, ‘Introduction: the projects of comparison’ in Annelise Riles (ed), Rethinking the Masters of Comparative Law (Hart Publishing 2001) 2.
40. See, among others, John Bell, ‘Comparing public law’ in Andrew Harding and Esin Orücü (eds), Comparative Law in the 21st Century (Kluwer Law international 2002) 235; Vicki C. Jackson and Mark Tushnet (eds), Defining the Field of Comparative Constitutional Law (Praeger 2002); Günther Frankenberg,
‘Comparing constitutions: ideas, ideals, and ideology—toward a layered narrative’ (2006) 4 International Journal of Constitutional Law 439; Ran Hirschl, ‘The question of case selection in comparative constitutional law’ (2005) 53 American Journal of Comparative Law 125.
constitutional ideas the key question—Teubner suggested—is whether constitutional theory can be generalized and transposed from the national terrain to the international sphere.41
The migration of constitutional ideas has been criticized on several grounds. Critics high- light the risk of judges making or transforming the law rather than interpreting or applying it.
Often arbitrators rely on national cases without theoretically explaining why. In other cases, the fact that arbitrators are embedded in a network—for instance, they were former constitu- tional judges, or former judges of other international courts and tribunals—may determine convergence because of informal ties. In turn this may cause a selection bias and increase the risks of importing, not necessarily the best qualitative models, but those which are more familiar to the adjudicators. Sovereignty concerns—critics contend—also matter as courts should not impose “foreign moods, fads, or fashions” on their audiences, as this would infringe the principle of separation of power and undermine the very legitimacy of the adjudicators.42 Furthermore, literal and historical interpretations demand that adjudicators rely on the text of the applicable law.
More fundamentally, as Zumbansen highlights, the question is whether the migration of constitutional ideas can be isolated from the historical and cultural context of the same.43 Zumbansen suggests that “a closer look” should be given to methodology and the historical, cultural, and social background of the item to borrow. In fact “[c] lose reading of national nar- ratives of administrative governance reveals particular connotations of regulatory power and of the relationship between different institutions (legislature, executive, judiciary and admin- istrative agencies).”44
At the macro-level, the argument goes that international investment arbitration is com- parable to public law adjudication. Given the fact that under most investment treaties, states have agreed to give arbitrators a comprehensive jurisdiction over what are essentially regu- latory disputes, investment treaty arbitration has been viewed as public law adjudication.45 Authors postulate the existence of a “global administrative space”: “a space in which the strict dichotomy between domestic and international has largely broken down, in which admin- istrative functions are performed in often complex interplay between […] institutions on different levels […].”46 Under this theoretical framework, investor-state arbitration has been
41. Günther Teubner, ‘Fragmented foundations: societal constitutionalism beyond the nation state’ in Petra Dobner and Martin Loughlin (eds), The Twilight of Constitutionalism? (Oxford University Press 2010) 328.
42. Lawrence v Texas, 123 Ct 2472, 2495 (2003) (Scalia J) and Foster v Florida, 537 U.S. 990 (2002) (Thomas J).
43. Zumbansen, ‘Transnational comparisons’ (n 37) 16 (asking whether the migration of ideas can be ‘con- ceived in near to complete isolation of the historical-intellectual contexts in which the very concepts … ha[d]
their origin’ and pinpointing the need to ‘understand the potential of bringing the hidden histories of a par- ticular legal field to light as they feed into the conceptualization on a world scale’).
44. ibid.
45. Gus Van Harten and Martin Loughlin, ‘Investment treaty arbitration as a species of global admin- istrative law’ (2006) 17(1) European Journal of International Law 121; Van Harten (n 3); Gus Van Harten,
‘The public-private distinction in the international arbitration of individual claims against the state’
(2007) 56(2) International and Comparative Law Quarterly 371, 372; Douglas (n 5); David Schneiderman, Constitutionalizing Economic Globalization: Investment Rules and Democracy’s Premise (Oxford University Press 2008); Santiago Montt, State Liability in Investment Treaty Arbitration: Global Constitutional Law and Administrative Law in the BIT Generation (Hart Publishing 2009); Stephan W. Schill, ‘Enhancing interna- tional investment law’s legitimacy: conceptual and methodological foundations of a new public law approach’
(2011) 52 Virginia Journal of International Law 57.
46. Nico Krisch and Benedict Kingsbury, ‘Introduction: global governance and global administrative law in the international legal order’ (2006) 17(1) European Journal of International Law 1.
conceptualized as a global administrative law (GAL) creature,47 which impels states to con- form to global administrative (and constitutional) law principles.48 Adjudication over a state’s acta jure imperii implies a significant departure from the conventional use of international arbitration in the commercial sphere.49 Arbitral awards ultimately shape the relationship between state, on the one hand, and private individuals on the other.50 Arbitrators determine matters such as the legality of governmental activity, the degree to which individuals should be protected from regulation, and the appropriate role of the state.51
Nevertheless, other analogies have been proposed at the macro-level,52 and international law scholars prefer to analogize investment treaty arbitration to other forms of international dispute settlement. As Crawford suggests, “[i] nvestment law, […] is about the way in which we bring the state under some measure of control, which is the main aspiration of general international law.”53 At the end of the day, investment treaty arbitrations are conducted on the basis of international treaties; their specific function is to settle disputes in conformity with international law.54 Therefore arbitral tribunals are analogous to other international courts and tribunals. Furthermore, constitutional adjudication addresses a broader range of questions than investment treaty arbitration, as constitutions encompass a broader range of individual entitlements than international investment treaties, despite some overlapping.55 In addition, the principal remedy in case of violation of investment treaty provisions is the award of com- pensation rather than restoration to the status quo ante (restitutio in integrum), as is the case with regard to constitutional adjudication.
Given the international law setting of investment treaty arbitration, it would be prob- lematic to automatically transpose the experience of any particular jurisdiction to the inter- national level. Only insofar as a discrete number of constitutional experiences constitute evidence of state practice or general principles of law can they assume relevance in the context of international law adjudication. Another instance in which a given constitutional practice may be relevant is when the applicable law is national law. Constitutional review may vary from jurisdiction to jurisdiction, reflecting the preferences of society—for example, as to the allocation of power between the different branches of government. Against this background,
47. Van Harten and Loughlin (n 45) 121 (suggesting that ‘international investment arbitration—pursuant to regional and bilateral investment treaties—offers the clearest example of global administrative law, strictly construed, yet to have emerged.’).
48. For a critical assessment of this theory, see Carol Harlow, ‘Global administrative law: the quest for prin- ciples and values’ (2006) 17(1) European Journal of International Law 187.
49. Traditionally, public international law has distinguished the conduct of a state between acta jure imperii and acta jure gestionis, with regard to its public or private nature. See Douglas (n 5) 221–22.
50. Van Harten (n 3) 9.
51. Muthucumaraswamy Sornarajah, ‘The clash of globalizations and the international law on foreign invest- ment’ (2003) 12 Canadian Foreign Policy 17.
52. Anthea Roberts, ‘Clash of paradigms: actors and analogies shaping the investment treaty system’ (2013) 107 American Journal of International Law 45.
53. James Crawford, ‘International protection of foreign direct investment: between clinical isolation and systematic integration’ in Rainer Hofmann and Christian J. Tams (eds), International Investment Law and General International Law—from Clinical Isolation to Systemic Integration? (Nomos 2011) 22.
54. Stephan W Schill, ‘System-building in investment treaty arbitration and lawmaking’ (2011) 12 German Law Journal 1083, 1088.
55. See Amnon Lehavi and Amir N. Licht, ‘BITs and pieces of property’ (2011) 36 Yale Journal of International Law 115, 131.