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When in Europe: Customary International Law and EU Competence in the Sphere of External Action

Published online by Cambridge University Press:  06 March 2019


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European Union law must be interpreted and its scope delimited, to the extent possible, consistent with the relevant rules of international law. Article 3(5) of the Treaty on European Union (TEU) provides that “the EU shall uphold and promote … the strict observance and the development of international law.” A similar legal commitment can be found in the constitutions of most EU Member States, which in some cases is about delegation of powers, whilst in others it concerns the achievement of global objectives. Article 3(5) of the TEU is also reminiscent of the judicial canon laid down by the United States Supreme Court in Charming Betsy regarding the affirmation of international norms by the Congress. The Charming Betsy doctrine of statutory construction requires national legislation (an American statute) to be construed so as not to raise conflict with international law where possible.

Special Issue: EU Law qua Global Governance Law
Copyright © 2011 by German Law Journal GbR 


1 Consolidated Version of the Treaty on European Union art. 3(5), Feb. 7, 1992, 2010 O.J. (C 83/01) [hereinafter TEU].Google Scholar

2 For example, while Article 25 of the German Constitution refers to the transfer of sovereign powers vis-à-vis international law, Article 2 (2) of the Greek Constitution concerns adherence to the rule of international law as a means of strengthening peace and justice and enhancing the relations between citizens and states.Google Scholar

3 Murray v. The Charming Betsy, 6 U.S. (2 Cranch) 64 (1804).Google Scholar

4 For an analysis of this case, see Frederick C. Leiner, The Charming Betsy and the Marshall Court, 45 Am. J. Legal Hist. 1 (2001) and Curtis A. Bradley, The Charming Betsy Canon, Separation of Powers and Customary International Law, 121 Harv. L. Rev. 1215 (2008).Google Scholar

5 See, e.g., International Law as Law of the European Union (Enzo Cannizzaro, Paolo Palchetti & Ramses Wessel eds., 2011); The Europeanisation of International Law: The Status of International Law in the EU and Its Member States (Jan Wouters, Andre Nollkaemper & Erika De Wet eds., 2008); International Law Aspects of the European Union (Martti Koskenniemi ed., 1998).Google Scholar

6 Consolidated Version of the Treaty on the Functioning of the European Union arts. 216(2), 350, Dec. 13, 2007, 2010 O.J. (C 83/01) [hereinafter TFEU].Google Scholar

7 Id. at art. 351.Google Scholar

8 TEU, supra note 1, at arts. 42(2), 42(7).Google Scholar

9 TEU, supra note 1, at art. 6.Google Scholar

10 Piet Eeckhout, EU External Relations Law 326 (2d ed. 2011).Google Scholar

11 TFEU, supra note 6, at art. 216(2) (stating that treaties concluded by the EU are binding on EU institutions and its Member States and form an integral part of EU law).Google Scholar

12 Case C-181/73, R. & V. Haegeman v. Belgian State, 1974 E.C.R. 449, para. 5.Google Scholar

13 Case C-22/70, Comm'n v. Council, 1971 E.C.R. 263 [hereinafter ERTA].Google Scholar

14 Joined Cases C-21, 22, 23, 24/72, Int'l Fruit Co. NV v. Produktschap voor Groenten en Fruit, 1972 E.C.R. 1219 [hereinafter International Fruit].Google Scholar

15 Case C-104/81, Hauptzollamt Mainz v. C.A. Kupferberg & Cie KG, 1982 E.C.R. 3641 (quoting Case C-6/64, Costa v. E.N.E.L., 1964 E.C.R. 1141).Google Scholar

16 See International Fruit; Case C-280/93, Ger. v. Council, 1994 E.C.R. 4973; Case C-69/89, Nakajima All Precision Co. v. Council, 1991 E.C.R. I-02069.Google Scholar

17 This refers to the language of “sa nature spécifique originale” first utilized by the CJEU in Costa. The language of autonomy has been relevant in defining the relationship between EU law and international law. This is most prominent in recent cases like Joined Cases C-402/05 and C-415/05, Kadi v. Council & Comm'n, 2008 E.C.R. I-6351 [hereinafter Kadi]. In Kadi, the international legal norms (i.e. UN Resolutions) from which EU law measures or regulations were derived from did not formally bind the EU. In such cases, the CJEU takes the view that such international legal norms do not form an integral part of EU law. See also Jam Willem Van Rossem, The EU at Crossroads: A Constitutional Inquiry into the Way International Law Is Received Within the EU Legal Order, in International Law as Law of the European Union 59, 63 (Enzo Cannizzaro, Paolo Palchetti & Ramses A. Wessel eds., 2011).Google Scholar

18 See Berkey, Judson Osterhoudt, The European Court of Justice and Direct Effect for GATT: A Question Worth Revisiting, 9 Eur. J. Int'l L. 626, 629 (1998) (criticizing the CJEU's doctrine).Google Scholar

19 Kadi at 2. It is worth noting that the last decision of the “Kadi Saga” took place before the General Court in Case T-85/09, Kadi v. Comm'n, 2010 E.C.R. II-5177 (commonly called Kadi II). This decision has been appealed by the Commission, the Council, and the UK. See Case C-584/10 P, Kadi v. Comm'n, 2011 OJ C72/9 (appeal made by Commission); Case C-593/10 P, Kadi v. Comm'n, 2011 OJ C72/9-10 (appeal made by Council).Google Scholar

20 Case T-69/00, FIAMM & FIAMM Techs., Inc. v. Council & Comm'n, 2005 E.C.R. II-5393 (discussing the possibility of non-contractual liability of the EU stemming from its breach of WTO obligations). See also Marco Dani, Remedying European Legal Pluralism: The FIAMM and Fedon litigation and the Judicial Protection of International Trade Bystanders, 21 Eur. J. Int'l. L. 303 (2010) (commenting on the FIAMM case).Google Scholar

21 Article 38(1)(d) also provides for a subsidiary source of international law, namely, “judicial decisions and the teachings of the most highly qualified publicists of the various nations.” As it will be explained below, treaty and custom depend on the consent of states. On the other hand, general principles do not require state practice as a precondition to emerge. This means that courts can have recourse to them even though states have not given their express consent. See also Ian Brownlie, Principles of Public International Law (6th ed., 2003).Google Scholar

22 Case C-366/10, Air Transport Ass'n of Am. v. Sec'y of State for Energy and Climate Change, 2011 E.C.R. 00 [hereinafter ETS judgment].Google Scholar

23 Statute of the International Court of Justice, 3 Bevans 1179 (1945).Google Scholar

24 Restatement (Third) of Foreign Relations Law of the United States, § 102(2) (1987).Google Scholar

25 See Jonathan I. Charney, The Persistent Objector Rule and the Development of Customary International Law, 56 Brit. Yearbook Int'l l. 1 (1985).Google Scholar

26 N. Sea Continental Shelf (Ger. v. Den. & Neth.), 1969 I.C.J. 3, 38-39, para. 63 (Feb. 20).Google Scholar

27 See Dodge, William S., Withdrawing from Customary International Law: Some Lessons from History, 120 Yale L.J. 169 (2010); Hazel Fox, The Law of State Immunity (2d ed. 2008).Google Scholar

28 See Case C-292/05, Lechouritou v. Dimosio tis Omospondiakis Dimokratias tis Germanias, 2007 E.C.R. I-01519.Google Scholar

29 Vienna Convention on the Law of Treaties art. 64, May 23, 1969, 1155 U.N.T.S. 331, 8 ILM 679 [hereinafter Vienna Convention].Google Scholar

30 Legality of the Threat or Use of Nuclear Weapons, 1996 I.C.J. 226 (July 8).Google Scholar

31 See Carlo Focarelli, International Law as Social Construct: The Struggle for Global Justice 314 (2012); Sabine Michalowski, Unconstitutional Regimes and the Validity of Sovereign Debt: A Legal Perspective 72-74 (2007).Google Scholar

32 James W. Garner, The Doctrine of Rebus Sic Stantibus and the Termination of Treaties, 21 Am. J. Int'l L. 509 (1927) (quoting Kwang-Sheng Yang, China Abrogating Unfair Treaties with the Powers, 25 Current Hist. 967, 968 (1927)).Google Scholar

33 Vienna Convention, supra note 29, at art. 26 (outlining the pacta sunt servanda principle).Google Scholar

34 Joined Cases C-241 & 242/91, Radio Telefis Eireann (RTE) & Independent Television Publications Ltd (ITP) v. Comm'n, 1995 E.C.R., I-743, para. 84; see also Case C-301/08, Bogiatzi v. Deutscher Luftpool, 2009 E.C.R. I-10185, para. 19.Google Scholar

35 This provision provides that, “the rights and obligations arising from agreements concluded before 1 January 1958 or, for acceding States, before the date of their accession, between one or more Member States on the one hand, and one or more third countries on the other, shall not be affected by the provisions of the Treaties.”Google Scholar

36 Case C-364/10, Hung. v. Slovk., 2012 E.C.R. _____ (opinion of Advocate General Bot), available at Scholar

37 Case C-286/90, Anklagemyndigheden v. Poulsen & Diva Navigation Corp., 1992 E.C.R., I-6019, para. 10 [hereinafter Poulson]; see also Case C-27/11, Vinkov v. Nachalnik Administrativno-nakazatelna deynost 2012 E.C.R. _____, available at, para. 33 (quoting Poulsen).Google Scholar

38 See Ahmed, Tawhida & Israel de Jesús Butler, The European Union and Human Rights: An International Law Perspective, 17 Eur. J. Int'l L. 771, 778 (2006).Google Scholar

39 See Case C-533/08, TNT Express Nederland BV v. AXA Versicherung AG, 2010 E.C.R. I-4104, para. 65 (opinion of Advocate General Kokott).Google Scholar

40 See, e.g., Case C-162/96, Racke GmbH & Co. v. Hauptzollamt Mainz, 1998 E.C.R. I-3655, paras. 24, 45, 46 [hereinafter Racke]; Case C-386/08, Firma Brita GmbH v. Hauptzollamt Hamburg-Hafen, 2010 E.C.R. I-01289, para. 42; Case C-63/09, Walz v. Clickair SA, 2010 E.C.R. 2010 I-04239, para. 16 (opinion of Advocate General Mazak); Case C-118/07, Comm'n v. Fin., 2009 E.C.R. I-10889, para. 39.Google Scholar

41 Case C-508/08, Comm'n v. Malta, 2010 E.C.R. I-10589, para. 4 (opinion of Advocate General Sharpston) [hereinafter Malta Sharpston opinion].Google Scholar

42 Racke, at para. 49 (stressing of this point by CJEU).Google Scholar

43 Case C-344/04, IATA & ELFAA v. Dep't Trans., 2006 E.C.R. I-403, para. 40; Case T-338/08, Stichting Natuur en Milieu & Pesticide Action Network Europe v. Comm'n, 2012 E.C.R. _____, para. 72, available at Scholar

44 Vienna Convention, supra note 29, at art. 31 (stating that a treaty is to be interpreted in good faith according to the ordinary meaning to be given to its terms in their context and in the light of its object and purpose).Google Scholar

45 Poulsen, at para. 10.Google Scholar

46 See Convention on the Privileges and Immunities of the United Nations art. 11, Feb. 13, 1946, 1 U.N.T.S. 15, 90 U.N.T.S. 327.Google Scholar

47 See Cudak v. Lithuania App. No. 15869/02 (Eur. Ct. H.R. Mar. 23, 2010), para. 60 (discussing the application of the State-immunity rule in a sexual harassment case); Sabeh El Leil v. France, No. 34869/05, (Eur. Ct. H.R. June 29, 2011), para. 52 (applying State-immunity in a suit for lost wages).Google Scholar

48 See Racke, at paras. 45-46 (“concerning a customs debt arising on the importation into Germany of certain quantities of wine originating in the Socialist Federal Republic of Yugoslavia”).Google Scholar

49 Jan Wouters & Dries Van Eeckhoutte, Giving Effect to Customary International Law Through European Community Law 6-18 (Inst. for Int'l Law, Working Paper No 25 – June 2002), available at [hereinafter Wouters].Google Scholar

50 See id. at 7-11. See, e.g., Case 41/74, Van Duyn v. Home Office, 1974 E.C.R. 1337, para. 22. In Van Duyn, the CJEU emphasized that under customary international law, a state is precluded from refusing its own nationals the right of entry and residence.Google Scholar

51 See Wouters, supra note 49, at 11-14. See, e.g., Case C-149/96, Portugal v. Council, 1999 E.C.R. I-8395, paras. 34-35. In Portugal v. Council, the CJEU highlighted the pacta sunt servanda principle as entailing bonafide performance of international agreements.Google Scholar

52 See Wouters & Eeckhoutte, supra note 49, at 14-16. See, e.g., Case C-135/08, Rottman v. Bayern, 2010 E.C.R. I-1449, para. 39. In Rottman, the CJEU, in line with its established case law, affirmed the principle under international law that Member States may lay down the conditions for their citizens’ acquisition and loss of nationality (as long as the pay due regard to their EU law obligations).Google Scholar

53 See Wouters, supra note 49, at 16-18.Google Scholar

54 Joined Cases 89, 104, 114, 116, 117, 125, 126, 127, 128, 129/85, A. Ahlström Osakeyhtiö v. Comm'n, 1988 E.C.R. 5193, para. 49 (opinion of Advocate General Darmon).Google Scholar

55 See Case C 135/08, Rottmann, 2010 E.C.R. I-3655, at para. 18.Google Scholar

56 Malta Sharpston opinion (noting that although Malta is not a party to the Vienna Convention it provides a guide of customary international law).Google Scholar

57 TEU, supra note 1, at art. 3(5).Google Scholar

58 See Case T-115/94, Opel Austria GmbH v. Council, 1997 E.C.R. II-0039, paras. 83, 90 & 93 (recognizing the principal of good faith and expectations in international agreements); see also Case C-372/97, Italy v. Comm'n, 2004 E.C.R. I-3679, paras. 116-18 (acknowledging that parties’ expectations must be considered); Joined Cases C-74 & 75/00, Falck Spa. v. Comm'n, 2002 E.C.R. I-7869, para. 140 (“[I]n the absence of any provision in that regard, the fundamental requirement of legal certainty has the effect of preventing the Commission from indefinitely delaying the exercise of its powers.”); Case T-308/00, Salzgitter AG v. Comm'n, 2004 E.C.R. II-1933, para. 166 (noting that a participant must plead a legitimate expectation).Google Scholar

59 See Schütze, Robert, On “Middle Ground”: The European Community and Public International Law, in Highest Courts and the Internationalisation of Law: Challenges and Changes 35, 44 (Sam Muller & Marc Louth eds., 2009).Google Scholar

60 Case C-144/04, Mangold v. Helm, 2005 E.C.R. I-9981, para. 74.Google Scholar

61 See Racke. Google Scholar

62 Id. at para. 46.Google Scholar

63 Id. at paras. 48-49, 52. See also Case T-338/08, Stichting Natuur en Milieu v. Comm'n, 2012 E.C.R. _____, para. 56, available at In Stichting Natuur en Milieu, “[T]he Court examined the validity of a regulation in the light of customary international law in so far as it found that ‘the individual concerned was invoking fundamental rules of customary international law against the disputed regulation, which had been taken pursuant to those rules and deprived that individual of the rights to preferential treatment granted to it by the Cooperation Agreement.'’” Id. Google Scholar

64 See ETS judgment (relying on customary international law in considering the inclusion of aviation activities in greenhouse gas emission schemes).Google Scholar

65 See Case T-396/09, Vereniging Milieudefensie v. Comm'n, 2012 E.C.R. _____, para. 56, available at (citing Racke).Google Scholar

66 See ETS judgment at para. 101.Google Scholar

67 See Case C-154/11, Mahamdia v. Algeria, 2012 E.C.R. _____, para. 17 (opinion of Advocate General Mengozzi), available at Scholar

68 See Case Comment on Racke, 117 Int'l L. Reports 399, 423 (2000).Google Scholar

69 See Conforti, Benedetto & Labella, Angelo, Invalidity and Termination of Treaties: The Role of National Courts, 1 Eur. J. Int'l L. 44, 58, 65 (1990) (discussing the operation of treaties in conjunction with customary international law); see also Lea Brilmayer, Federalism, State Authority, and the Preemptive Power of International Law, 1994 Sup. Ct. Rev. 295, 310-14 (1994) (providing an analysis of federal common law); Beth Stephens, The Law of Our Land: Customary International Law as Federal Law After Erie, 66 Fordham L. Rev. 393 (1997) (discussing the role of customary international law in the United States).Google Scholar

70 Council Directive 2003/87/EC, 2003 O.J. (L 275) 32; Council Directive 2008/101/EC, 2009 O.J. (L 8) 3.Google Scholar

71 Council Directive 2008/101/EC, 2009 O.J. (L 8) 3.Google Scholar

72 See Zeben, Josephine van, Respective Powers of the European Member State and Commission Regarding Emissions Trading and Allowance Allocation, 12 Envtl. L. Rev. 216, 222-24 (2010) (discussing the impact of recent court decisions on the European energy market).Google Scholar

73 Council Directive 2008/101/EC, 2009 O.J. (L 8) 17. To be more specific, the 2008 Directive imposed a cap on the total quantity of aviation emissions and required aircraft operators to surrender emissions allowances for the entirety of flights departing from or arriving in the EU. In certain circumstances, it required aircraft operators wishing to carry out aviation activities in excess of their free allocation to purchase allowances at auction. The 2008 Directive also provided for an excess penalty of €100 per ton of carbon dioxide to be imposed on aircraft operators that do not surrender sufficient allowances. It also introduced the possibility of an EU-wide operating ban on the aircraft operator concerned in the event an aircraft operator failed to comply with the requirements of the Directive.Google Scholar

74 International Civil Aviation Organization, Inclusion of International Civil Aviation in the European Union Emissions Trading Scheme and Its Impact 2 (Working Paper C-WP/13790, Oct. 17, 2011), available at (Examining “the issue of inclusion of international civil aviation in the European Union Emissions Trading Scheme (EU ETS) and its impact”).Google Scholar

75 For a more detailed analysis of this aspect of the judgment, see Burgess Salmon, Case Comment, Air Transport Association of America v. Secretary of State for Energy and Climate Change (C-366/10), 14 Envtl. L. Rev. 81 (2012).Google Scholar

76 U.N. Charter art. 1, para. 7.Google Scholar

77 It should be noted that the Chicago Convention/ICAO is internationally recognized as the forum through which international aviation issues, including greenhouse gas emissions, should be regulated.Google Scholar

78 See U.N. Convention on the Law of the Sea art. 87, 89, 212, & 222, Dec. 10, 1982, 1833 U.N.T.S 397; U.N. Convention on the High Seas art. 2, Apr. 29, 1958, 13 U.S.T. 2313, 450 U.N.T.S. 82; Fisheries Jurisdiction (U.K. v. Ice.), 1974 I.C.J. 3, para. 50 (July 25).Google Scholar

79 Case C-366/10, Air Transp. Ass'n of America v. Sec'y of State for Energy and Climate Change, 2011 E.C.R. _____, para. 144, available at (opinion of Advocate General Kokott) [hereinafter ETS judgment Kokott's opinion].Google Scholar

80 Id. at para. 154.Google Scholar

81 See Case C-308/06, Intertanko v. Sec'y of State for Trans., 2008 E.C.R. I-4057 (determining liability on the high seas).Google Scholar

82 See Case C-50/00 P, Unión de Pequeños Agricultores v. Council, 2002 E.C.R. I-6677 (determining whether an individual has standing).Google Scholar

83 See ETS judgment Kokott's opinion at para. 134.Google Scholar

84 See ETS judgment at para. 101.Google Scholar

85 See id. at paras. 45, 104.Google Scholar

86 See id. at para. 106.Google Scholar

87 Since this decision, under the auspices of ICAO, the Moscow Joint Declaration was issued providing that, “the EU and its Member States must cease application of the Directive 2008/101/EC to airlines/aircraft operators registered in third States.” Joint Declaration of the Moscow Meeting on Inclusion of Civil Aviation in the EU-ETS, Feb. 21, 2012, available at The Declaration was signed by twenty-three states. Id. See also Robert Ireland, The EU Aviation Emissions Policy and Border Tax Adjustments 7 (World Customs Org. Policy Research Brief, July 2012), available at Scholar

88 ETS judgment at para. 107.Google Scholar

89 See Case C-224/01, Köbler v. Austria, 2003 E.C.R. I-10239 (determining which courts have jurisdictions to hear cases that may be contrary to Community law).Google Scholar

90 See Racke at para. 52.Google Scholar

91 Id. at para. 48.Google Scholar

92 See Poulsen (interpreting certain technical measures for fishery resources).Google Scholar

93 See Racke at paras. 48, 52.Google Scholar

94 See id. at para. 48.Google Scholar

95 Bundesverfassungsgericht [BVerfG – Federal Constitutional Court], Case No. 2 BvR 197/83, Oct. 22, 1986, 73 BVerfGE 339 (Ger.) (deciding to no longer examine Community laws for compatibility with German laws, entrusting that to the EU courts and lawmakers)Re Honeywell, Federal Constitutional Court (Second Chamber), 2011 1 C.M.L.R. 33.Google Scholar

96 Bundesverfassungsgericht [BVerfG – Federal Constitutional Court], Case No. 2 BvR 2261/06 (Aug. 26, 2010), Scholar

97 See ETS judgment Kokott's opinion at para. 127.Google Scholar

98 For a discussion on whether the shipping industry could be included in the European Emissions Trading Scheme to reduce greenhouse gas emissions, see Mariella Kremlis, The Inclusion of the Shipping Industry in the EU ETS, 19 Eur. Energy & Envtl. L. Rev. 145 (2010). On the issue of extraterritoriality, see parallels in the Appellate Body Report, US-Import Prohibition of Certain Shrimp and Shrimp Products, WT/DS58/AB/R (Oct. 12, 1998).Google Scholar

99 Interestingly, Danni argues that, “if the Court of Justice wishes to take seriously pacta sunt servanda, it should enforce those findings [i.e. that WTO-inconsistent measures infringe primary and secondary international trade obligations] in the [EU] legal order and, notably, it should rule that also for [EU] purposes the Commission and Council acted illegally.” Dani, supra note 20, at 325.Google Scholar

100 See Case T-69/00, FIAMM v. Council, 2005 E.C.R. II-5393, para. 21. The General Court concluded that the conditions governing such no-fault liability were not satisfied because the damage suffered by the applicants was not “unusual and special in nature.” Id. at para. 155. For a critique of the FIAMM test, see Alberto Alemanno, The Fiamm Judgment or “Going Bananas”! A Missed Opportunity to Distribute the Costs of European Community's Non-compliance with WTO Rulings Across Society, in The ECJ Under Siege: New Constitutional Challenges for the ECJ 208, 213 (Giuseppe Martinico & Filippo Fontanelli eds., 2009).Google Scholar

101 See Bartels, Lorand, The WTO Legality of the Application of the EU's Emission Trading System to Aviation, 23 Eur. J. Int'l L. 429 (2012); Alemanno, Alberto, Judicial Enforcement of the WTO Hormones Ruling Within the European Community: Toward EC Liability for the Non-Implementation of WTO Dispute Settlement Decisions?, 45 Harvard Int'l L.J. 547 (2004) (“By demonstrating the opportunity to introduce a minimal standard of direct effect into the world trading system, the recognition of the invocability of WTO rulings, embryonically developed by the ECJ in the Biret case, may lay the groundwork for a new role for private parties in the dispute settlement system.”).Google Scholar

102 Scott, Joanne & Rajamani, Lavanya, EU Climate Change Unilateralism, 23 Eur. J. Int'l L. 469 (2012).Google Scholar

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