28 Wena Hotels Limited c. Egypt, CIADI 2002 (ICSID Case nº ARB/98/4), Decision on Application for Annulment, Feb. 5, 2002, para. 38-40: “38. This discussion brings into light the various views expressed as to the role of international law in the context of Article 42(1). Scholarly opinion, authoritative writings and some ICSID decisions have dealt with this matter. Some views have argued for a broad role of international law, including not only the rules embodied in treaties but also the rather large definition of sources contained in Article 38(1) of the Statute of the International Court of Justice. Other views have expressed that international law is called in to supplement the applicable domestic law in case of the existence of lacunae. In Klockner I the ad hoc Committee introduced the concept of international law as complementary to the applicable law in case of lacunae and as corrective in case that the applicable domestic law would not conform on all points to the principles of international law. There is also the view that international law has a controlling function of domestic applicable law to the extent that there is a collision between such law and fundamental norms of international law embodied in the concept of jus cogens”.
29 Wena Hotels Limited c. Egypt, CIADI 2002 (ICSID Case nº ARB/98/4), Decision on Application for Annulment, Feb. 5, 2002, para. 38-40: “39. Some of these views have in common the fact that they are aimed at restricting the role of international law and highlighting that of the law of the host State. Conversely, the view that calls for a broad application of international law aims at restricting the role of the law of the host State. There seems not to be a single answer as to which of these approaches is the correct one. The circumstances of each case may justify one or another solution. However, this Committee’s task is not to elaborate precise conclusions on this matter, but only to decide whether the Tribunal manifestly exceeded its powers with respect to Article 42(1) of the CSID Convention. Further, the use of the word ‘may’ in the second sentence of this provision indicates that the Convention does not draw a sharp line for the distinction of the respective scope of international and of domestic law and, correspondingly, that this has the effect to confer on to the Tribunal a certain margin and power for interpretation”.
30 Wena Hotels Limited c. Egypt, CIADI 2002 (ICSID Case nº ARB/98/4), Decision on Application for Annulment, Feb. 5, 2002, para. 38-40: “40. What is clear is that the sense and meaning of the negotiations leading to the second sentence of Article 42(1) allowed for both legal orders to have a role. The law of the host State can indeed be applied in conjunction with international law if this is justified. So too international law can be applied by itself it the appropriate rule is found in this other ambit”.
31 Antonio R. Parra, “Applicable Law in Investor-State Arbitration”, en Arthur W. Rovine (ed.), Contemporary Issues in International Arbitration and Mediation: The Fordham Papers (2007), Boston, Brill Nijhoff, 2008, pp. 1-12.
32 Gaillard y Banifatemi, ob. cit., p. 399.
33 Laura Victoria García-Matamoros y Walter Arévalo-Ramírez, “Procedimiento para la solución de diferencias en el arbitraje de inversión: el Centro Internacional de Arreglo de Disputas relativas a Inversiones (CIADI)”, en Laura Victoria García-Matamoros y Diana Carolina Ávila Medina (eds.), Procedimiento, litigio y representación ante tribunales internacionales, Bogotá, Universidad del Rosario, 2017, p. 445.
34 Gaillard y Banifatemi, ob. cit., p. 373.
35 Continental Casualty Company v. The Argentine Republic, Caso ICSID nº ARB/03/9.
36 LG&E Energy Corp., LG&E Capital Corp., LG&E International, Inc. v. República Argentina, Caso ICSID nº ARB/02/1.
37 Enron Corporation y Ponderosa Assets, L.P. c. República Argentina, Caso ICSID nº ARB/01/3.
38 Sempra Energy International c. República Argentina, Caso ICSID nº ARB/02/16.
39 CMS Gas-Transmission Company c. República Argentina, Caso ICSID, nº ARB/01/8.
40 Walter Arévalo, “Responsabilidad internacional del Estado por hechos internacionalmente ilícitos: las causales de exclusión de ilicitud, su contenido y escenarios de aplicación”, en Ricardo Abello Galvis (ed.), Derecho internacional: varias visiones un maestro. Liber amicorum en homenaje a Marco Gerardo Monroy Cabra, Bogotá, Universidad del Rosario, 2015, pp. 29-53.
41 Robert D. Sloane, “On the use and abuse of necessity in the law of state responsibility”, en American Journal of International Law, vol. 106, n° 3 (2012), pp. 447-508.
42 Walter Arévalo y Laura García-Matamoros, “El estado de necesidad en el arbitraje de inversión: su invocación consuetudinaria y convencional en los arbitrajes Enron, Sempra, CMS, LG&E y Continental ante el Centro Internacional de Arreglo de Diferencias relativas a Inversiones (CIADI)”, en Anuario Mexicano de Derecho Internacional, vol. 17 (2017), pp. 469-512.
43 International Court of Justice, Case Concerning the Gabčíkovo-Nagymaros Project (Hungary/Slovakia), Judgment of 25 September 1997, ICJ Reports, 1997, para. 7-84.
44 CMS Gas Transmission Company v. Argentine Republic, ICSID Case nº ARB/01/8, Annulment Proceeding, Decision of the Ad Hoc Committee on the Application for Annulment of the Argentine Republic.
45 Gazzini y De Brabandere (eds.), ob. cit., p. 127.
46 Azurix c. Argentina, CIADI nº ARB/01/12, Laudo, parágrafos 66-67 [idioma original]: “66. Article 42(1) has been the subject of controversy on the respective roles of municipal law and international law. It is clear from the second sentence of Article 42(1) that both legal orders have a role to play, which role will depend on the nature of the dispute and may vary depending on which element of the dispute is considered. The Annulment Committee in Wena v. Egypt considered that ‘The law of the host State can indeed be applied in conjunction with international law if this is justified. So too international law can be applied by itself if the appropriate rule is found in this other ambit’. 67. Azurix’s claim has been advanced under the BIT and, as stated by the Annulment Committee in Vivendi II, the Tribunal’s inquiry is governed by the ICSID Convention, by the BIT and by applicable international law. While the Tribunal’s inquiry will be guided by this statement, this does not mean that the law of Argentina should be disregarded. On the contrary, the law of Argentina should be helpful in the carrying out of the Tribunal’s inquiry into the alleged breaches of the Concession Agreement to which Argentina’s law applies, but it is only an element of the inquiry because of the treaty nature of the claims under consideration”.
47 Azurix c. Argentina, CIADI nº ARB/01/12, Laudo, parágrafos 66-67.
48 Schill, ob. cit.
49 Total S.A. c. The Argentine Republic, CIADI nº ARB/04/01, 2010: “122. Indeed, the most difficult case is (as in part in the present dispute) when the basis of an investor’s invocation of entitlement to stability under a fair and equitable treatment clause relies on legislation or regulation of a unilateral and general character. In such instances, investor’s expectations are rooted in regulation of a normative and administrative nature that is not specifically addressed to the relevant investor […]. 123 […] The determination of a breach of the standard requires, therefore, ‘a weighing of the Claimant’s reasonable and legitimate expectations on the one hand and the Respondent’s legitimate regulatory interest on the other’. 127 Thus an evaluation of the fairness of the conduct of the host country towards an investor cannot be made in isolation, considering only their bilateral relations. The context of the evolution of the host economy, the reasonableness of the normative changes challenged and their appropriateness in the light of a criterion of proportionality also have to be taken into account”.
50 Stephan Schill et ál., General Public International Law and International Investment Law: A Research Sketch on Selected Issues, Berlín, Institute of Economic Law, 2009.
51 Stephan W. Schill, “General principles of law and international investment law”, en International Investment Law, Boston, Brill Nijhoff, 2012, pp. 133-181.
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