1 Referring to ‘the general principles of law recognized by civilized nations’ as a source of the law applicable by the ICJ under Art. 38(1c) of the ICJ Statute, Judge McNair observed that ‘the duty of international tribunals in this matter is to regard any features or terminology which are reminiscent of the rules and institutions of private law as an indication of policy and principles rather than as directly importing these rules and institutions’ (International Status of South-West Africa, Separate Opinion of by Sir Arnold McNair to the Advisory Opinion of 11 July 1950, [1950] ICJ Rep. 146, at 148). This is all the most appropriate with regard to principles of adjudication. See in the same direction also A. P. Sereni, Principi generali del diritto e processo Internazionale (1955); P. Weil, ‘Le droit international en quête de son identité’, (1992/VI) 237 RCADI 9, at 146; O. Schachter, International Law in Theory and Practice (1991), 54.

2 See G. Cordero-Moss, ‘Tribunal’s Powers versus Party Autonomy’, in P. Muchlinski, F. Ortino and C. Schreuer (eds.), The Oxford Handbook of International Investment Law (2008), at 1207. While the Author applies private international law and international commercial law parameters to the analysis of international investment arbitration, for the purposes of the present article, neither the adversarial nor the inquisitorial models are regarded as the matrix of international adjudication and arbitration, which are considered to have their own independent international configuration. See also Kaufmann-Kohler, G., ‘The Arbitrator and the Law: Does He/She Know it? Apply It? How? And a Few More Questions’, (2005) 21 Arb. Int., at 632.Google Scholar

3 G. Morelli, ‘La théorie générale du procès international’, (1937) 61 RCADI 253, at 311 ff. See also H. Thirlway, The International Court of Justice (2016), at 38 ff.

4 To the contrary, on the nuanced differences between international adjudication and arbitration – though, focusing on the procedural rules on the conduct of proceedings, rather than on principles of adjudication – see S. Forlati, The International Court of Justice. An Arbitral Tribunal or a Judicial Body? (2014), 23 ff. See also R. Kolb, ‘General Principles of Procedural Law’, in A. Zimmerman et al. (eds.), The Statute of the International Court of Justice: A Commentary (2012), at 876.

5 See C. Brown, A common law of international adjudication (2007). Kolb similarly refers to ‘principles common to the ICJ, international arbitrations (inter-state and possibly also commercial), standing international tribunals (e.g. the ITLOS, the ECHR, etc.) and possibly also bodies such as the Human Rights Committee under the International Covenant on Civil and Political Rights’ (Kolb, supra note 4, at 875).

6 ‘Consultative Meeting of Legal Experts, Fifth Session 19 February 1964’, in ICSID (ed.), History of the ICSID Convention: Documents Concerning the Origin and the Formulation of the Convention (1968), Vol. II-1, at 423, available at icsid.worldbank.org/en/Documents/resources/History%20of%20ICSID%20Convention%20-%20VOLUME%20II-1.pdf. See also E. De Brabandere, Investment Treaty Arbitration as Public International Law (2014).

7 Walde, T. W., ‘Procedural Challenges in Investment Arbitration under the Shadow of the Dual Role of the State: Asymmetries and Tribunals’ Duty to Ensure, Proactively, the Equality of Arms’, (2010) 26 Arb. Int., at 3 CrossRefGoogle Scholar. See also S. Wittich, ‘The Limits of Party Autonomy in Investment Arbitration’, in C. Knahr, C. Koller and A. Reinisch (eds.), Investment and Commercial Arbitration. Similarities and Divergences (2010), 47, at 50 ff.

8 As stressed by Eric De Brabandere, also with a view to distinguishing investment treaty arbitration from international commercial arbitration, ‘[b]eing founded in public international law, investment tribunals and arbitrators are subjected to some specific principles imported from public international litigation’ (De Brabandere, supra note 6, at 100).

9 As recently put by the ILC Special Rapporteur on Protection of the Atmosphere, Professor Shinya Murase, ‘jura novit curia puts a limit on the restriction imposed by non ultra petita’ (S. Murase, Fifth report on the protection of the atmosphere, UN Doc. A/CN.4/711 (2018), at 45, para. 90).

10 G. Fitzmaurice, The Law and Procedure of the International Court of Justice (1986), vol. 2, at 524.

11 Request for Interpretation of the Judgment of 20 November 1950 in the Asylum Case (Colombia v. Peru), Judgment of 27 November 1950, [1950] ICJ Rep. 395, at 402.

12 Barcelona Traction, Light and Power Company, Limited (Belgium v. Spain), Preliminary Objections, Judgment of 5 February 1970, [1970] ICJ Rep. 3, at 37, para. 49.

13 Boundary dispute between Argentina and Chile concerning the frontier line between boundary post 62 and Mount Fitzroy, Decision of 21 October 1994, (2006) XXII UNRIAA 3, at 26, para. 77.

14 Ibid.

15 See, for all, F. Rosenfeld, ‘Iura Novit Curia in International Law’, (2017) 6 EIAR 132. On the different configurations of the principle in hand in domestic and international adjudication see J. Verhoeven, ‘Jura Novit Curia et le juge international’, in P-M Dupuy et al. (eds.), Völkerrecht als Wertordnung: Festschrift für Christian Tomuschat – Common Values in International Law: Essays in Honour of Christian Tomuschat (2006), 635, at 637 ff.

16 See also Rosenfeld, ibid., at 132.

17 Against the application of jura novit curia to international (commercial) arbitration on the assumption that there would be no lex fori for an international arbitral tribunal, G. Kaufmann-Kohler, ‘Iura novit arbiter: Est-ce bien raisonnable?’, in A. Héritier and L. Hirsch (eds.), De Lege Ferenda. Réflexions sur le droit désirable en l’honneur du Professeur Alain Hirsch (2004), 71, at 74.

18 With the exception where the BIT provides for the application of the domestic law of the host state, including its conflict of laws rule.

19 As recently observed by the ILC, in international adjudication ‘[t]he line between “fact” and “law” is often obscured’, adding that ‘[b]ased on jura novit curia, the Court can in principle apply any law to any fact, and in theory can evaluate evidence and draw conclusions as it sees appropriate as long as the Court complies with the non ultra petita rule); these are all legal matters. Given its judicial function and under jura novit curia, the Court needs to sufficiently understand the meaning of each related technical fact in the case at hand’ (ILC, ‘Report of the International Law Commission. Seventieth session’ (30 April–1 June and 2 July–10 August 2018) UN Doc. A/73/10 (2018), at 200, note 991).

20 See Fitzmaurice, supra note 10, at 531.

21 Continental Shelf (Libyan Arab Jamahiriya v. Malta), Merits, Judgment of 3 June 1985, [1985] ICJ Rep. 3, at 23, para. 19.

22 Ibid., at 24, para. 19.

23 See Fitzmaurice, supra note 10, at 524.

24 See H. Lauterpacht, ‘Some Observations on the Prohibition of “Non Liquet” and the Completeness of the Law’, in F. M. Van Asbeck (ed.), Symbolae Verzijl: présentées au professeur J. H. W.Verzijl à l’occasion de son LXX-ième anniversaire (1958), 196, at 217.

25 See, amongst others, D. Bodansky, ‘Non Liquet and the Incompleteness of International Law’, in L. Boisson de Chazournes and P. Sands (eds.), International Law, the International Court of Justice and Nuclear Weapons (1999), 153, at 155.

26 See A. Bjorklund and J. Brosseau, ‘Sources of Inherent Powers in International Adjudication’, (2018) 6 EIAR 1.

27 See supra note 19; see also M. Kazazi, Burden of Proof and Related Issues: A Study on Evidence before International Tribunals (1996), at 42–9.

28 See G. Fitzmaurice, ‘The Problem of Non-Liquet: Prolegomena to a Restatement’, in C. R. Rousseau and S. Bastid (eds.), Mélanges offerts à Charles Rousseau: la communauté international (1974), 89, at 96.

29 Case concerning the location of boundary markers in Taba between Egypt and Israel, decision of 29 September 1988, (2006) X UNRIAA 1, at 65 ff., paras. 238 ff. (Taba). See P. Weil, ‘Some Observations on the Arbitral Award in the Taba Case’, (1989) 23 Isr. Law Rev. 1, at 25; E. Lauterpacht, ‘The Taba Case: Some Recollections and Reflections’, ibid., 443, at 468;

30 1965 Convention on the settlement of investment disputes between States and nationals of other States, 575 UNTS 159.

31 C. Schreuer, ‘Three Generation of ICSID Annulment Procedures’, in E. Gaillard and Y. Banifatemi (eds.), Annulment of ICSID Awards (2004), 17, at 30.

32 J. Paulson, ‘International Arbitration and the Generation of Legal Norms: Treaty Arbitration and International Law’, in A. J. van den Berg (ed.), International Arbitration 2006: back to basics? (2007), 879, at 879.

33 See infra note 101.

34 Klöckner Industrie-Anlagen GmbH and others v. United Republic of Cameroon and Société Camerounaise des Engrais, ICSID Case No. ARB/81/2, Decision on Annulment of 3 May 1985, (1994) 2 ICSID Rep. 9, at 117, para. 56; emphasis added (Klöckner I).

35 Ibid., at 117 ff., paras. 57 ff.

36 On the inextricable relationship between facts and law in litigation, see supra notes 19 and 27. As stated by the sole arbitrator, Giuditta Cordero-Moss, in the oft-quoted Bogdanov case ‘[a]s long as the Arbitral Tribunal limits its evaluation to the facts as presented by the parties, it remains free, within the borders of the applicable law particularly, as long as it remains within the frame of the legal sources mentioned in the proceeding), to give the legal qualifications and determine the legal consequences that it deems appropriate, even if they were not pleaded by the parties’ (Iurii Bogdanov, Agurdino-Invest Ltd. and Agurdino-Chimia JSC v. Republic of Moldova, Award of 22 September 2005, at 14, available at www.italaw.com/sites/default/files/case-documents/ita0094_0.pdf).

37 Compañia de Aguas del Aconquija and Vivendi Universal v. Argentina, ICSID Case No. ARB/97/3, Decision on Annulment of 3 July 2002, para. 85, available at www.italaw.com/sites/default/files/case-documents/ita0210.pdf (Vivendi I).

38 Caratube International Oil Company LLP v. The Republic of Kazakhstan, ICSID Case No. ARB/08/12, Decision on Annulment of 21 February 2014, paras. 92 ff., available at www.italaw.com/sites/default/files/case-documents/italaw3082.pdf (Caratube).

39 Quiborax S.A., Non Metallic Minerals S.A. and Allan Fosk Kaplún v. Plurinational State of Bolivia, ICSID Case No. ARB/06/2, Award of 16 September 2015, para. 92, available at www.italaw.com/sites/default/files/case-documents/italaw4389.pdf. In the same vein, see also Vestey Group Ltd v. Bolivarian Republic of Venezuela, ICSID Case No. ARB/06/4, Award of 5 April 2016, para. 118, available at www.italaw.com/sites/default/files/case-documents/italaw7230.pdf; and Churchill Mining and Planet Mining v. Pty Ltd v Republic of Indonesia, ICSID Case No. ARB/12/14, Award of 6 December 2016, para. 236, available at www.italaw.com/sites/default/files/case-documents/italaw7893.pdf.

40 The Committee emphasized that ‘[a]n arbitral tribunal is not limited to referring to or relying upon only the authorities cited by the parties. It can, sua sponte, rely on other publicly available authorities, even if they have not been cited by the parties, provided that the issue has been raised before the tribunal and the parties were provided an opportunity to address it’ (Daimler Financial Services AG v. Argentine Republic, ICSID Case No. ARB/05/1, Decision on Annulment of 7 January 2015, para. 295, available at www.italaw.com/sites/default/files/case-documents/italaw4092.pdf). And by ‘authority’ one intends ‘a judicial decision, statute, or rule of law that establishes a principle; precedent’ (Collins English Dictionary, online edition, available at www.collinsdictionary.com/dictionary/english/authority).

41 C. Schreuer, L. Malintoppi and A. Reinisch (eds.), The ICSID Convention. A Commentary (2009), at 816.

42 Ibid.

43 Supra, Section 2.3.

44 Supra, note 41.

45 See in general A. Gattini, A. Tanzi and F. Fontanelli (eds.), General Principles of Law and International Investment Arbitration (2018); A. Tanzi, ‘Conclusions: Testing General Principles of Law in International Investment Law: between Principles and Rules of International Law’, in M. Andenas et al. (eds.), General Principles and the Coherence of International Law (2019), 297.

46 Supra, note 21.

47 Vivendi I, supra note 37, para. 86.

48 Enron Corporation and Ponderosa Assets, L.P. v. Argentine Republic, ICSID Case No. ARB/01/3, Decision on the Application for Annulment of the Argentine Republic of 30 July 2010, para. 375. See also, amongst others, the ad hoc committee in Patrick Mitchell. It argued that an ICSID Tribunal ‘is not, strictly speaking, subject to any obligation to apply a rule of law that has not been adduced; this is but an option … for which reason it is not possible to draw any conclusion from the fact that the arbitral Tribunal did not exercise it’ (Patrick Mitchell v. Democratic Republic of the Congo, ICSID Case No. ARB/99/7, Decision on the Application for Annulment of the Award, 1 November 2006, para. 57).

49 Enron, ibid., para. 376.

50 See supra, text at notes 19, 27 and 36.

51 Murase, supra note 9, at 45, para. 90 (emphasis added).

52 See I. F. Shihata, The Power of the International Court to Determine its Own Jurisdiction. Compétence de la compétence (1965); R. Kolb, ‘General principles of procedural law’, in A. Zimmermann et al. (eds.), The Statute of the International Court of Justice: A Commentary (2006), 794, at 812; H. Thirlway, The Law and Procedure of the International Court of Justice: Fifty Years of Jurisprudence (2013), vol. I, at 755 ff.; Forlati, supra, note 4, at 85 ff.

53 Rio Grande Irrigation and Land Company, Ltd. (Great Britain) v. United States, Decision of 28 November 1923, (2006) VI UNRIAA 131, at 135–6.

54 Statute of the ICJ, Art. 36, para. 6; 1982 United Nations Convention on the Law of the Sea Montego Bay, 1833 UNTS 3, Art. 288, para. 4; 1950 Convention for the Protection of Human Rights and Fundamental Freedoms, 213 UNTS 221, Art. 49; 1969 American Convention on Human Rights, 1144 UNTS 123, Art. 62, para. 3. Whilst the latter provision does not expressly address the power at issue, the Inter-American Court’s case law has considered such power as encompassed by the Court’s general power to interpret the Convention (see J. M. Pasqualucci, The Practice and Procedure of the Inter-American Court of Human Rights (2003), at 34). As for inter-state case law, see supra note 52.

55 Ioan Micula, Viorel Micula, S.C. European Food S.A, S.C. Starmill S.R.L. and S.C. Multipack S.R.L. v. Romania, ICSID Case No. ARB/05/20, Decision on Jurisdiction and Admissibility of 24 September 2008, para. 65, available at www.italaw.com/sites/default/files/case-documents/ita0530.pdf (emphasis added). See also more recently, 1. Vattenfall AB; 2. Vattenfall GmbH; 3. Vattenfall Europe Nuclear Energy GmbH; 4. Kernkraftwerk Krummel GmbH & Co. oHG; 5. Kernkraftwerk Brunsbuttel GmbH & Co. oHG v Federal Republic of Germany, ICSID Case No. ARB/12/12, Decision on the Achmea Issue, 31 August 2018, paras. 18–19, available at www.italaw.com/sites/default/files/case-documents/italaw9916.pdf.

56 Libananco Holdings Co. Limited v. Republic of Turkey, ICSID Case No ARB/06/8, Decision on Annulment of 22 May 2013, paras. 222–3, available at www.italaw.com/sites/default/files/case-documents/ita0928.pdf (Libananco).

57 Given space constraints, this circumstance cannot be addressed separately in the present article. See for all in inter-state litigation, Alexandrov, S. A., ‘Non-Appearance before the International Court of Justice’, (1995) 33 Columb. J. Transnat’l L. 41 Google Scholar; and the commentary to Art. 45 of the ICSID Convention in Schreuer, Malintoppi and Reinisch, supra note 41, at 708 ff.

58 ‘Both Parties have therefore taken the position that compliance with Art. VII(2) of the BIT is an issue of jurisdiction rather than admissibility. The question arises whether the Tribunal is bound by the Parties’ shared legal position. After a careful consideration of the applicable legal framework, the Tribunal concludes that it is not.’ (Içkale Insaat Limited Sirketi v. Turkmenistan, ICSID Case No. ARB/10/24, Award of 8 March 2016, para. 239, available at www.italaw.com/sites/default/files/case-documents/italaw7163_1.pdf (Içkale)).

59 Another illustrative case in which the tribunal followed on jurisdictional matters an extensive application of jura novit curia, hence compressing ne ultra petita, is represented by the decision on jurisdiction in the formerly known case Mobil (Venezuela Holdings, B.V., et al. v. Bolivarian Republic of Venezuela, ICSID Case No. ARB/07/27, Decision on Jurisdiction of 10 June 2010, available at www.italaw.com/sites/default/files/case-documents/ita0538.pdf (Venezuela Holding)). There, the issue was whether Art. 22 of the Venezuelan Investment Law constituted Venezuela’s standing consent to ICSID arbitration. Mobil argued that Art. 22 functioned essentially like a treaty whereas Venezuela maintained that it had to be interpreted and applied according to Venezuelan municipal law. The tribunal disagreed with both parties on the point while following instead the ICJ case law on unilateral acts accepting that court’s jurisdiction. See also F. G. Sourgens, A Nascent Common Law. The Process of Decision-making in International Legal Disputes between States and Foreign Investors (2015), at 56.

60 Empresas Lucchetti, S.A. and Lucchetti Peru, S.A. v. The Republic of Peru, ICSID Case No. ARB/03/4, Decision on Annulment of 5 September 2007, para. 99, available at www.italaw.com/sites/default/files/case-documents/ita0277.pdf (Lucchetti).

61 Azurix Corp. v. The Argentine Republic, ICSID Case No. ARB/01/12, Decision on Annulment of 1 September 2009, para. 66, available at www.italaw.com/sites/default/files/case-documents/ita0065.pdf (Azurix). The tribunal went on to stress that ‘[t]hus, an award will only be annulled under that provision on grounds that the tribunal lacked jurisdiction or exceeded jurisdiction if the lack or excess of jurisdiction was manifest’ (ibid.). In Enron, one may not find a criterion for the distinction between a ‘manifest’ and a ‘simple’ excess of power in the ‘distinction between non-application of the applicable law (which is a ground for annulment), and an incorrect application of the applicable law (which is not), although this is a distinction that may not always be easy to draw’ (Enron, supra note 48, para. 68).

62 See, respectively, Statute of the ICJ, Art. 41, and Rules of the International Court of Justice, Art. 75, para. 2 (as amended on 14 April 2005); 1982 United Nations Convention on the Law of the Sea Montego Bay, supra note 54, Art. 39, para. 1, and Art. 290, para. 1, and Rules of the Tribunal, UN Doc. ITLOS/8, 17 March 2009, Art. 89, para. 5; Rules of the European Court of Human Rights, Rule 39;1969 American Convention on Human Rights, supra note 54, Art. 63, para. 2.

63 See, for all, C. Miles, Provisional Measures before International Courts and Tribunals (2017), at 308. On the inter-state courts’ and tribunals’ power to adopt, as well as amend, provisional measures motu proprio, see also Forlati, supra note 4, at 90 ff.

64 The Articles above mentioned state, respectively: ‘[t]he arbitral tribunal may, at the request of a party, grant interim measures’ (UNCITRAL Arbitration Rules, Art. 26, para. 1); ‘[t]he Arbitral Tribunal may, at the request of a party, grant any interim measures it deems appropriate’ (Arbitration Rules of the Arbitration Institute of the Stockholm Chamber of Commerce, Art. 32, para. 1); ‘the arbitral tribunal may, at the request of a party, order any interim or conservatory measures it deems appropriate’ (International Chamber of Commerce Arbitration Rules, Art. 28, para. 1); ‘[t]he Arbritral Tribunal shall have the power, upon application of any party … to order [interim and conservatory measures]’ (London Chamber of Commerce International Arbitration Rules, Art. 25, para. 1).

65 Victor Pey Casado and President Allende Foundation v. Republic of Chile, ICSID Case No. ARB/98/2, Decision on Provisional Measures of 25 September 2001, para 16, available at www.italaw.com/sites/default/files/case-documents/ita0629.pdf (Spanish).

66 One may wonder whether the right to be heard would limit the autonomy of the adjudicator also when it would issue a provisional measure proprio motu. The inter-state case law seems to indicate against this.

67 ICSID Arbitration Rules, Rule 39, para. 2.

68 Vivendi I, supra note 37, para. 69. See more recently Total S.A. v. The Argentine Republic, ICSID Case No. ARB/04/01, Decision on Annulment of 1 February 2016, para. 167, available at www.italaw.com/sites/default/files/case-documents/italaw7084.pdf.

69 Klöckner Industrie-Anlagen GmbH and others v. United Republic of Cameroon and Société Camerounaise des Engrais, ICSID Case No. ARB/81/2, Decision on Annulment of 17 May 1990, (2009) 14 ICISD Rep. 8, para. 9.15 (Klöckner II).

70 Amco Asia Corporation and others v. Republic of Indonesia, ICSID Case No. ARB/81/1, Decision on Annulment of 17 December 1992, (1993) 1 ICSID Rep. 569, para. 1.17 (Amco II).

71 C. B. Lamm, E. R. Hellbeck and D. P. Rosenberg, ‘The Two Annulment Decisions in Amco Asia and “Non-Application” of Applicable Law by ICSID Tribunals’, in D. D. Caron, S. W. B. Schill and A. Cohen Smutny (eds.), Practising Virtue: Inside International Arbitration (2015), 689, at 705.

72 Schreuer, Malintoppi, Reinisch, supra note 41, at 901, paras. 8 ff.

73 C. Schreuer, ‘From ICSID Annulment to Appeal Half Way Down the Slippery Slope’, (2011) 10 LAPICT 211.

74 G. Bottini, ‘Reform of the Investor-State Arbitration Regime: the Appeal Proposal’, in J. E. Kalicki and A. Joubin-Bret (eds.), Reshaping the Investor-State Dispute Settlement System: Journeys for the 21st Century (2015), 455.

75 Schreuer, supra note 73, at 222.

76 D. Caron, ‘Framing the Word of ICSID Annulment Committees’, (2012) 6 World Arb. & Med. R. 173; Friedland, P. D. and Brumpton, P., ‘Rabid Redux: The Second Wave of Abusive ICSID Annulments’, (2012) 27 Am. U. Int’l L. Rev. 727 Google Scholar.

77 CMS Gas Transmission Company v. The Republic of Argentina, ICSID Case No. ARB/01/8, Decision of the ad hoc Committee on the Application for Annulment of the Argentine Republic of 25 September 2007, available at www.italaw.com/sites/default/files/case-documents/ita0187.pdf (CMS).

78 Caron, supra note 76, at 183.

79 Amco II, supra note 70; Klöckner II, supra note 69; Maritime International Nominees Establishment v. Republic of Guinea, ICSID Case No. ARB/84/4 (MINE); Compañiá de Aguas del Aconquija S.A. and Vivendi Universal S.A. v. Argentine Republic, ICSID Case No. ARB/97/3 (Vivendi II); Enron, supra note 48; Sempra Energy International v. The Argentine Republic, ICSID Case No. ARB/02/16 (Sempra); Venezuela Holding, supra note 59; Victor Pey Casado, supra note 65; TECO Guatemala Holdings, LLC v. Republic of Guatemala, ICSID Case No. ARB/10/23 (TECO).

80 Amco II, supra note 70; Klöckner II, supra note 69; Vivendi II, ibid.; Victor Pey Casado, supra note 65.

81 ‘[T]he expression “manifestly exceed its powers” concerned the cases referred to … as ultra petita’. Mr. Ghanem went so far as to suggest that ‘the expression ultra petita [should] be used instead of “excès de pouvoir”’, History of the ICSID Conventionsupra note 6, vol. II-2, at 850, available at icsid.worldbank.org/en/Documents/resources/History%20of%20ICSID%20Convention%20-%20VOLUME%20II-2.pdf. See also, History of the ICSID Convention, ibid., at 58.

82 1958 Convention on the Recognition and Enforcement of Foreign Arbitral Awards, 330 UNTS 3 (1958 NY Convention). See M. B. Feldman, ‘The Annulment Proceedings and the Finality of ICSID Arbitral Awards’, (1987) 2 ICSID Rev. 85, at 99 ff.

83 1958 NY Convention, ibid., Art. V, para. 1, let. c).

84 Enron, supra note 48, para. 68.

85 The committee observed that ‘it is necessary to differentiate between a failure to apply the proper law and an error in applying the law. The first is a ground for annulment under Art. 52, the second is not. Reviewing the substantive reasoning by which the tribunal arrived at its conclusions would demand reviewing how the tribunal applied the law or interpreted the same, resulting in the committee acting as a court of appeal, thereby exceeding the powers granted to it by Art. 52 of the ICSID Convention. In order to decide whether the tribunal misapplied or misinterpreted the law to the matter decided, the committee would necessarily have to evaluate the facts and evidence as well as the correctness of the legal principles submitted by the parties, assessed and applied by the tribunal. Obviously, that is the function of an appellate court and not of an annulment committee. Failure to apply the law is part of the concept of manifest excess of powers and … should be self-evident, clear, obvious, flagrant and substantially serious. As stated above, this committee agrees with the views of Prof. Schreuer that there is a difference between a failure to apply the proper law and the misapplication of the applicable law, and that the latter does not constitute grounds for annulment, even if it is a “manifest error of law”, unless it is of such a magnitude as to amount to the non-application of the proper law as a whole’ (Impregilo S.p.A. v. Argentine Republic, ICSID Case No. ARB/07/17, Decision on Annulment of 24 January 2014, paras. 131–2, available at www.italaw.com/sites/default/files/case-documents/italaw3044.pdf (Impregilo)). See also the passage from Enron quoted supra note 84.

86 History of the ICSID Convention, supra note 6, at 849–52.

87 Consortium R.F.C.C. v. Kingdom of Morocco, ICSID Case No. ARB/00/6, Decision on Annulment of 18 January 2006, para. 226, in (2011) 26 ICSID Rev. 184.

88 Compañiá de Aguas del Aconquija S.A. and Vivendi Universal S.A. v. Argentine Republic, ICSID Case No. ARB/97/3, Decision on the Argentine Republic’s Request for Annulment of the Award rendered on 20 August 2007 of 10 August 2010, para. 252, available at www.italaw.com/sites/default/files/case-documents/ita0221.pdf (Vivendi II).

89 As recalled by Aron Broches, a failure to afford a party the opportunity to exercise such a right was envisaged precisely as a ground for annulment consisting of ‘a serious departure from a fundamental rule of procedure’. To that end, he argued that one such ‘[f]undamental rule’ would comprise, for instance, the so-called principles of natural justice, e.g. both parties must be heard and that there must be adequate opportunity for rebuttal’ (A. Broches, ‘Observations on the Finality of ICSID Awards’, (1991) 6 ICSID Rev. 320, at 331). See, inter alia, Maritime International Nominees Establishment v. Republic of Guinea, ICSID Case No. ARB/84/4, Decision on Annulment of 22 December 1989, para. 5.06, available at www.italaw.com/sites/default/files/case-documents/italaw8608.pdf (MINE); Wena Hotels Ltd. v. Arab Republic of Egypt ICSID Case No. ARB/98/4, Decision on Annulment of 28 January 2002, para. 57, available at www.italaw.com/sites/default/files/case-documents/ita0903.pdf (Wena Hotels); MTD Equity Sdn. Bhd. and MTD Chile S.A. v. Republic of Chile, ICSID Case No. ARB/01/7, Decision on Annulment, 21 March 2007, para. 49; CDC Group plc. v. Republic of Seychelles, ICSID Case No. ARB/02/14, Decision on Annulment of 29 June 2005, para. 49, available at www.italaw.com/sites/default/files/case-documents/italaw6344.pdf (CDC); Azurix, supra note 61, paras. 49 ff.

90 Vivendi I, supra note 37, para. 85.

91 See Caratube, supra note 38, paras. 93–4. See also, inter alia, Klöckner I, supra note 34, para. 91; Victor Pey Casado, supra note 65, Decision on the Application for Annulment of the Republic of Chile of 18 December 2012, para. 267, available at www.italaw.com/sites/default/files/case-documents/italaw1178.pdf.

92 This provision is reiterated by Rule 47(1i), of the ICSID Arbitration Rules according to which the award shall contain ‘the decision of the Tribunal on every question submitted to it, together with the reasons upon which the decision is based’.

93 De Brabandere, supra note 6, at 90.

94 Arbitral Award of 31 July 1989 (Guinea-Bissau v. Senegal), Judgment of 12 November 1991, [1991] ICJ Rep. 53.

95 De Brabandere, supra note 6, at 91.

96 Klöckner I, supra note 34, paras. 114–15; MINE, supra note 89, paras. 5.11–5.13; CDC, supra note 89, paras. 50, 56–7.

97 MINE, supra note 89, paras. 5.08–5.09; Wena Hotels, supra note 89, para. 81.

98 Klöckner I, supra note 34, paras. 115–16.

99 CDC, supra note 89, para. 75.

100 Amco Asia Corporation and others v. Republic of Indonesia, ICSID Case No. ARB/81/1, Decision on Annulment of 16 May 1986, (1993) 1 ICSID Rep. 413, paras. 86 ff (Amco I).

101 Tulip Real Estate and Development Netherlands B.V. v. Republic of Turkey, ICSID Case No. ARB/11/28, Decision on Annulment of 30 December 2015, para. 45, available at www.italaw.com/sites/default/files/case-documents/italaw7037.pdf (Tulip); EDF International S.A. SAUR International S.A. and Leon Participaciones Argentinas S.A. v. Argentine Republic, ICSID Case No. ARB/03/23, Decision on Annulment of 5 February 2016, para. 73, available at www.italaw.com/sites/default/files/case-documents/italaw7090.pdf (EDF). See also Amco II, supra note 70, para. 1.20; MINE, supra note 89, paras. 4.09–4.10; Vivendi I, supra note 37, para. 66.

102 EDF, ibid., para. 73.

103 Supra note 32.

104 B. Simma and D. Pulkowski, ‘Two Worlds, but Not Apart: International Investment Law and General International Law’, in M. Bungenberg, J. Griebel and S. Hobe (eds.), International Investment Law (2015), 361.