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Secession from a Member State and EU Membership: the View from the Union


Arguments in favour of a more explicit and clearer EU stance on secession from a member state – two different cases for secession and their implications – the inadmissibility of unilateral secession within the EU – consensual secession does not create a legal entitlement for automatic membership – the need to follow the route of Article 49 TEU – no need for a specific secession provision in EU treaties

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CSIC - Consejo Superior de Investigaciones Científicas, Institute of Public Goods and Policies (IPP-CCHS), Madrid, Spain.

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1 Scotland’s First Minister, Nicola Sturgeon, declared that a new referendum would be unstoppable if the UK were to vote to leave the EU: see F. Perraudin ‘Sturgeon: new Scottish referendum “probably unstoppable” if UK votes to leave EU”, The Guardian, 16 October 2015, <>, visited 24 May 2016.

2 The regional Council of Veneto approved Law, No. 16/2014, calling for a referendum on independence, which the Italian Constitutional Court declared unconstitutional (judgment No. 118/2015).

3 ‘It is not for the Commission to express a position on questions of internal organisation related to the constitutional arrangements of a particular Member State’. Answer given by President Juncker on behalf of the Commission EN E-011776/2015 (21 September 2015). The European Commission spokesperson, Pia Ahrenkilde Hansen, gave an identical response earlier in relation to Scotland (Euractiv, ‘Scottish referendum to clash with European elections’, 16 October 2012, available at <>, visited 24 May 2016. The Committee of Regions expressed the same view in its opinion: ‘Devolution in the European Union and the place for local and regional self-government in EU policy making and delivery’, 100th. plenary session, 11-12 April 2013, CIVEX-V-034. European Council President Van Rompuy declared ‘it is not for me to express a position on questions of internal organisation related to the constitutional arrangements in a Member State’. Remarks by President of the European Council, Madrid, 12 December 2013 EUCO 267/13 PRESSE 576 PR PCE 241.

4 See Athanassiou P. and Laulhe-Shaelou S., ‘EU Accession from Within?—An Introduction’, 33(1) Yearbook of European Law (2014) p. 335-384 and Brölmann C. and Vandamme T. (eds.), Secession within the Union. Intersection points of International and European Law (Amsterdam Centre for European Law and Governance, Amsterdam Center for International Law 2014), <>, visited 24 May 2016.

5 See, inter alia, Buchanan A., Justice, Legitimacy and self-determination (Oxford University Press 2004); see also Norman W., Negotiating Nationalism; Nation Building, Federalism and Secession in the Multinational State (Oxford University Press 2006). Crawford and Boyle opine that the principle of self-determination is controversial outside the colonial context: Crawford J. A. and Boyle A., ‘Annex. A. Opinion: Referendum on the Independence of Scotland – International Law Aspects’, in Scotland analysis: Devolution and the implications of Scottish independence (H.M. Government February 2013), <>, visited 24 May 2016. They refer to the Canadian Supreme Court ruling in the case of Quebec: ‘a right of secession under the principle of self-determination at international law where a “people” is governed as part of a colonial empire’. SCR, 20 August 1998, Case 2 217/1998 Reference re Secession of Québec.

6 Scotland’s Future: Your Guide to an Independent Scotland, Scottish Government, 26 November 2013, <>, visited 24 May2016. ‘Following a vote for independence, the Scottish Government will immediately seek discussions with the Westminster Government and with the member states and institutions of the EU to agree the process whereby a smooth transition to full EU membership can take place on the day Scotland becomes an independent country’. See also CATN, Les vies d’integració de Catalunya a la Unió Europea [The paths for integration of Catalonia to the European Union], Informe núm. 6 (Generalitat de Catalunya 2014). On the place of the EU in the Catalan debate, see Galán A. Galán, ‘Secesión de Estados y pertenencia a la Unión Europea: Cataluña en la encrucijada’ [Secession of States and belonging to the European Unión. Catalonia at the crossroad], No. 1 Istituzioni del Federalismo (2013) p. 95 at p. 101-104 .

7 Not even the Catalan anti-capitalist party CUP proposes abandoning the EU if Catalonia becomes independent. Its electoral manifesto calls for disobedience within an anti-democratic EU directed by financial elites, and questions the euro as an instrument for restricting economic sovereignty. CUP, Governmen-nos. El motor és la gent [Let’s govern us ourselves. People are the engine], <>, visited 24 May 2016. Conversely, the EU and the special status of Brussels within it (as EU capital and site of most EU institutional headquarters) form a constraint against the threatened partition of Belgium. See Laborderie V., ‘La fin de la Belgique et ses impossibilities: L’hypothèse d’une independence flamande à l’épreuve des faits’, 3 Outre-Terre. Revue européenne de géopolitique (2014) p. 114 ; and Popelier P. and Lemmens K., The Constitution of Belgium. A Contextual Analysis (Hart Publishing 2015).

8 Avery G., ‘Independentism and the European Union European’, 7 Policy Centre Policy Brief (May 2014).

9 I am grateful to one of the reviewers for this observation.

10 See, inter alia, Marks G. and Llamazares I., ‘La transformación de la movilización regional en la Unión Europea’, 22:1 Revista de Estudios Políticos (1995) p. 149 .

11 Juncker J.-C., A New Start for Europe: My Agenda for Jobs, Growth, Fairness and Democratic Change Political guidelines for the next European Commission Opening Statement in the European Parliament Plenary Session Strasbourg, 22 October 2014 ; Candidate for President of the European Commission Strasbourg, 15 July 2014, <>, visited 24 May 2016.

12 ‘Scottish independence: Jean-Claude Juncker “not referring to Scotland”’, BBC News, 15 July 2014, <>, visited 24 May 2016.

13 Weiler J.H.H., ‘Catalonian independence and the European Union’, 23/4 EJIL (2009) p. 909 ; and ‘Scottish independence and European Union Editorial’, 12/3 I-CON (2014) p. 507. See also Piris J.-C., ‘Political and legal aspects of recent regional secessionist trends within the European Union’, in C. Closa (ed.), Troubled Membership: Secession from a Member State and Withdrawal from the Union (Cambridge University Press to be published in 2016).

14 Written Evidence from Professor Sir David Edward, European and External Relations Committee Agenda 2nd Meeting, 2014 (Session 4) Thursday 23 January 2014.

15 Walker N., ‘Internal Enlargement in the European Union: Beyond Legalism and Political Expediency’, in Closa, supra n. 13 .

16 CATN, supra n. 6. From a standpoint that is critical with regard to secession, J. de Miguel also argues that the model of unilateral secession is not totally discarded in the TEU; Bárcenas J. de Miguel, ‘La cuestión de la secesión en la Unión Europea: una visión constitucional’, 165 Revista de Estudios Políticos (2014) p. 211 at p. 231.

17 Tajadura J., ‘Más allá de un asunto interno: secesionismo e integración europea’, 64 Análisis del Real Instituto Elcano ARI (22 December 2014), <>, visited 24 May 2016

18 Edward, supra n. 14. Inter alia, see also Kenealy D. and MacLennan S., ‘Sincere Cooperation, Respect for Democracy and EU Citizenship: Sufficient to Guarantee Scotland’s Future in the European Union?’, 20(5) European Law Journal (2014) p. 8 and Martín y Pérez de Nanclares J., Reflexiones jurídicas a propósito de una eventual declaración unilateral de independencia de Cataluña: un escenario político jurídicamente inviable, 24 September2015, p. 26 , <>, visited 28 May 2016.

19 For instance, Tajadura, supra n. 17

20 ECJ 8 March 2011, Case C-34/09, Ruiz Zambrano v Office national de l’emploi (ONEm). D. López Garrido (Coordinador), Cataluña ante la Unión Europea. Las consecuencias jurídicas de la independencia, Fundación Alternativas. Informe, September2015 p. 6-8, <>, visited 28 May 2016.

21 ECJ 10 October 1978, Case 148/77, Hansen v Hauptzollamt Flensburg. See, further, Crawford and Boyle, supra n. 5 and Ziller J., ‘The European Union and the territorial scope of European territories’, 38 Victoria University of Wellington Law Review (2007) p. 51 .

22 A ‘continuator’ state is a predecessor state that retains its legal identity and existence in spite of a change of circumstances, such as loss of territory. See the terminology in Crawford and Boyle, supra n. 5.

23 de Miguel, supra n. 16 and Edward, supra n. 14, make the same distinction.

24 The agreement committed both parties to respect the result of the referendum and to work together in the best interests of the people of Scotland and of the rest of the UK following the referendum. Agreement between the United Kingdom Government and the Scottish Government on a referendum on independence for Scotland, 15 October 2012, <>, visited 28 May 2016.

25 Piris J.-C., ‘Cataluña y la Unión Europea’ [Catalonia and the European Union], El País, 29 August 2015 .

26 For instance, Libro Blanco — La transición nacional de Cataluña, (Generalitat de Cataluña 2014) p. 119.

27 For instance, López Garrido, supra n. 20 and Martín y Pérez de Nanclares, supra n. 18, p. 26.

28 M. González and L. Doncel, ‘Merkel reclama a Cataluña respeto al principio de integridad territorial’ [Merkel reclaims Catalonia the respect of the principle of territorial integrity], El País, 1 September 2015.

29 See, supra n. 21.

30 Tierney S. and Boyle K., ‘An Independent Scotland: The Road to Membership of the European Union’ ESRC Scottish Centre on Constitutional Change Briefing Paper 20 August 2014, p. 16 .

31 Bondía A. González, ‘La Unión Europea ante el reto del derecho a decidir’, in E. Segarra (ed.), ‘¿Existe el derecho a decidir? Preguntas y respuestas sobre el proceso abierto en Cataluña’ (Tibidabo Edicions 2014) p. 123 ; Martín J. Ridao, ‘La Unió Europea i els nous Estats sorgits per secessió dels seus membres. Una hipòtesi per Catalunya’, 113 Revista Jurídica de Catalunya (2014) p. 331 ; Martín J. Ridao and Bondía A. González, ‘La Unión Europea ante la eventual creación de nuevos Estados surgidos de la secesión de Estados miembros’, 27–28 Revista de Derecho de la Unión Europea (2014) p. 363 . These authors argue that, on the basis of the democratic values of Art. 2, unilateral secession is lawful. Although they recognise a potential contradiction between this and the duty to respect the ‘fundamental structures, political and constitutional’ of the Member States, ‘including ensuring the territorial integrity of the State’, they conclude that the Commission could sue a member state before the European Court of Justice for breach of the Treaties under Art. 258 TFEU if that state did not recognise the basic fundamental rights of EU citizens in this regard.

32 Similarly, Piris, supra n. 13 and Martín y Pérez de Nanclares, supra n. 18.

33 See also Piris, supra n. 13 and Tajadura, supra n. 17.

34 Crawford and Boyle, supra n. 5.

35 Answer given by Mr Prodi on behalf of the Commission (1 March 2004) Official Journal of the European Union C 84 E/422 3.4.2004.

36 See ‘Scotland and the EU: Barroso´s reply to Lord Tugendath’ <’s_reply_to_Lord_Tugendhat_101212.pdf>, visited 28 May 2016. In September 2013, a speaker from the Commission declared that if a territory of a member state declares its independence, it automatically stops belonging to the EU and becomes a third party. L. Abellán and M. Noguer, ‘Bruselas asegura que Cataluña saldría de la UE con la independencia’ [Brussels affirms that Catalonia would exit from the EU with independence], El País, 16 September 2013. In September 2015, the Commission again repeated its position though its speaker, Margaritis Schinas. C. Pérez, ‘Cataluña independiente estará automáticamente fuera de la UE’, El País, 17 September 2015. Several governments supported the Commission’s proposal (i.e. Spain, Ireland, Latvia and the Czech Republic). Referred to in Kenealy and MacLennan, supra n. 18. See their elaborated criticism of the Commission’s stance: ‘The commission, in adopting its current position, is failing to act in a manner consistent with the role it is charged with’. For a detailed overview of EP questions and the Commission’s responses on the issue, see Galán Galán, supra n. 6.

37 Piris, supra n. 13.

38 Van Rompuy, supra n. 3. He repeated this position in a later interview on SER Radio. Reported at Van Rompuy H., ‘La secesión no interesa ni a quienes la piden’ [Secession does not interest even to those asking for it], El País, 29 April 2014, <>, visited 28 May 2016.

39 Supra n. 3.

40 ECJ 29 September 1997, Case C-95/97, Région Wallonne v Commission of the European Communities para. 6.

41 Chamon M. and Loo G. Van der, ‘The Temporal Paradox of Regions in the EU Seeking Independence: Contraction and Fragmentation versus Widening and Deepening?’, 20(5) European Law Journal (2014) p. 613 at p. 619.

42 Avery G., ‘Could an independent Scotland join the European Union?’, European Policy Centre Policy Brief , 28 May 2014.

43 Inter alia, Kenealy and MacLennan, supra n. 18.

44 O’Neill A., ‘A Quarrel in a Faraway Country? Scotland, Independence and the EU’, Eutopia law blog, 14 November 2011, <>, visited 28 May 2016. O’Neill assumes that Scotland and a rump UK should each succeed to the UK’s existing membership of the EU, but now as two states rather than as one, and hence that both would retain their rights and obligations as EU members. For a criticism of this thesis, see Piris, supra n. 13.

45 Neil MacCormick coined the term ‘internal enlargement’ to refer to the possibility of existing member states dividing into new member states. See his contribution to the Convention on the Future of Europe Democracy at many levels: European constitutional reform CONV 298/02 <;jsessionid=R4x6LksLHZDzHqTylpbpDQCj1JFLTpl8Y3RpnF52sPG2pSTJ37mZ!-975318364?docId=105639&cardId=105639>, visited 28 May 2016. On the same, see, inter alia, Thorp A. and Thompson G., Scotland, Independence and the EU, House of Commons Research Briefings, 2011, p. 7 , <>, visited 28 May 2016 and J. Matas i Dalmases et al., L´ampliació interna de la Unió Europea. Anàlisi de les conseqüències juridicopolítiques per a la Unió Europea en cas de secessió o de dissolució d´un estat membre [The European Union internal enlargement. Analysis of juridical and political consequences in case of secession or dissolution of a member state] (Fundació Josep Irla 2010).

46 See Scotland´s future and CATN, supra n. 6.

47 Inter alia, Avery, supra n. 8, Edward, supra n. 14; S. Douglas-Scott, How Easily Could an Independent Scotland Join the EU?, July 2014, University of Oxford, Legal Research Papers, Paper No. 46/2014; see also Tierney and CATN, supra n. 6.

48 Inter alia, Crawford and Boyle, supra n. 5; Chamon and Van der Loo, supra n. 41; and Kenealy and MacLennan, supra n. 18.

49 Edward, supra n. 14.

50 Walker N. ‘Hijacking the Debate’, Scottish Constitutional Futures Forum Blog, <>, visited 28 May 2016. See also N. Walker, ‘Internal Enlargement in the European Union: Beyond Legalism and Political Expediency, in Closa, supra n. 13.

51 Cindy C., ‘Democratic authority from the outside looking in: States, common worlds and wrongful connections’, Journal of ethics & social philosophy (2011 Symposium).

52 Maduro M., ‘A New Governance for the European Union and the Euro: Democracy and Justice’, RSCAS Policy Paper 2012/11.

53 Maduro, supra n. 52; Somek A., ‘The Argument from Transnational Effects I: Representing Outsiders through Freedom of Movement’, 16 European Law Journal (2010) p. 315 and Somek A., ‘The Argument from Transnational Effects II: Establishing Transnational Democracy’, 16 European Law Journal (2010) p. 375 .

54 The Commission argued that, according to Art. 20 TFEU, only persons that have the nationality of a member state are EU citizens. Rather than stating the obvious, this response suggested that the loss of EU citizenship would follow as a consequence of secession when it added that ‘in case of secession of part of a member state, the solution would have to be found and negotiated within international legal order’. Respuesta a la pregunta planteada a la Comisión a propósito de la iniciativa sobre “El fortalecimiento de la participación ciudadana en la toma de decisiones sobre la soberanía colectiva”, C (2012) 3689 final, de 30 de mayo de 2012 (30 May 2012). This initiative sought to guarantee that the citizens of a new state resulting from the secession of a given territory would remain EU citizens. The same literal wording appears in the Response of the President of the Commission, Jose Manuel Durao Barroso, to the question of Maria Bizzoto, 28 August 2012; Doc. E-007453/2012. Similarly, see Piris, supra n. 13.

55 Douglas-Scott, supra n. 47.

56 Edward, supra n. 14. He concedes that it is still uncertain whether the ECJ would accept such a reference or answer such a question.

57 ECJ 2 March 2010, Case C-135/08, Janko Rottman v Freistaat Bayern. ‘The loss of nationality has to be amenable to judicial review in which it is for the national court to determine whether the legitimacy of a loss of nationality on grounds of deception is proportionate having regard to the consequences of the loss of rights for the individual (…) while also having regard to the gravity of the deception that would permit a Member State to withdraw nationality’. In Micheletti, the Court argued that decisions on nationality must have regard to Community law. ECJ 7 July 1992, Case C-369/90, Micheletti v Delegación del Gobierno en Cantabria.

58 Kenealy and MacLennan, supra n. 18.

59 Case C-34/09, Ruiz Zambrano, supra n. 20. See also Case C-135/09, Rottman, supra n. 57.

60 Kenealy and MacLennan, supra n. 18; Douglas-Scott, supra n. 47.

61 Tierney S., ‘Legal Issues Surrounding the Referendum on Independence for Scotland’, 9 European Constitutional Law Review (2013) p. 359-390 ; Avery, supra n. 42 and Edward, supra n. 14.

62 Tierney and Boyle, supra n. 30.

63 See supra n. 5.

64 ECJ 16 June 1993; Case C-325/91, France v The EC Commission. ‘The principle of legal certainty, which is part of the Community legal order, requires Community legislation to be clear and its application to be foreseeable for all interested parties. As a result of that requirement, any act intended to have legal effects must derive its binding force from a provision of Community law which prescribes the legal form to be taken by that act and which must be expressly indicated therein as its legal basis, failing which the act in question will be null and void’.

65 Tierney and Boyle, supra n. 30.

66 Hillion C., ‘Scotland and the EU: Comment by Christophe Hillion’, VerfassungBlog, 15 September 2014, <>, visited 28 May 2016.

67 Tierney and Boyle, supra n. 30.

68 Piris J.C., Written Evidence from Jean-Claude Piris to the European and External Affairs Committee of the Scottish Parliament, 23 January 2014, p. 28-29 ; Piris, supra n. 13; Chamon and Van der Loo, supra n. 41; Edward, supra n. 14; and Kenealy and MacLennan, supra n. 18.

69 Edward, supra n. 14; Tierney, supra n. 61; and Kenealy and MacLennan, supra n. 16.

70 Chamon and Van der Loo, supra n. 41.

71 Edward, supra n. 14.

72 See, for instance, Edward, supra n. 14.

73 Edward, supra n. 14; Tierney supra n. 61.

74 Inter alia, to secure an outcome that respects the continuing exercise of the rights currently conferred by EU law (e.g. Tierney and Boyle, supra n. 30); a swift agreement with the new State (Piris, supra n. 68); a pro tempore solution that would avoid unnecessary disruptions (Kenealy and MacLennan, supra n. 18); some short of transitional agreement (Avery, supra n. 9); K. Armstrong, ‘The reach and resources of European law in the Scottish independence referendum’, in Closa, supra n. 13 and Douglas-Scott, supra n. 47; or to negotiate Scotland’s accession (Tierney, supra n. 61).

75 For instance, Palomares Amat argues that the European Council could decide that EU law would apply in relation to the rights and obligations of the citizens of the newly independent region. But even if that were true (something really doubtful), then still this is not necessarily an agreement, nor does it necessarily entitle the authorities of the territory to become part of the agreement. Amat M. Palomares, ‘Las decisiones de los Jefes de Estado y de Gobierno, en el seno del Consejo Europeo, como categoría jurídica para regular, transitoriamente, la participación en la Unión Europea de nuevos Estados surgidos de la separación de Estados miembros’, 17 Revista d´Estudis autonòmics i federals (2013) p. 146 .

76 Walker, supra n. 15.

77 Avery, supra n. 42.

78 Douglas-Scott, supra n. 47.

79 CATN, supra n. 6.

80 Keating M., ‘Would an independent Scotland be in the European Union?’, in C. Jeffery and R. Perman (eds.), 16 Questions to think about for the referendum on 18 September (Birlinn Limited 2014) p. 46-49 .

81 Inter alia, Kenealy and MacLennan combine the sincere cooperation, Art. 50 and democratic process arguments to argue that the member states and the Commission would be obliged to enter into negotiations, and that failure to enter into such negotiations (via Art. 48) would hardly represent sincere cooperation. They furthermore argue that the dislocation caused to the single market, should part of its existing territory suddenly find itself expelled, would be significant, supra n. 18.

82 ECJ 29 April 2004, Case-338/01 Commission v Council. Also, Hillion, supra n. 66 and Piris, supra n. 68.

83 Piris, supra n. 13; López Garrido, supra n. 20; Hillion, supra n. 66 and Armstrong supra n. 74.

84 Piris, supra n. 13.

85 The Committee of Regions (Point 64) recalls that if a region, having achieved independence, wanted to join the EU, it would be required to make a formal application to the Council and to follow the accession procedure under Art. 49 TEU in the same way as any other country that wished to become an EU Member State, supra n. 3, Point 64.

86 The UK House of Commons Scottish Affairs Committee asserted that Scotland would have to follow the Art. 49 procedure: Scottish Affairs Committee - Twelfth Report, The Referendum on Separation for Scotland: Scotland’s Membership of the EU, 27 May 2014, <>, visited 28 May 2016.

87 Inter alia, Crawford and Boyle supra n. 5; Hillion, supra n. 66; Piris, supra n. ???; de Miguel, supra n. 16; López Garrido et al., supra n. 20; Galán Galán, supra n. 8; and Chamon and Van der Loo, supra n. 41.

88 Hillion, supra n. 66; Piris, supra n. 13.

89 Hillion, supra n. 66.

90 Piris, supra n 13; Walker, supra n 15.

91 Tajadura, supra n. 17.

92 de Miguel, supra n. 16.

93 Walker, supra n. 15 and C. Fasone, ‘Secession and the Ambiguous Place of Regions under EU Law’, in Closa, supra n. 13.

94 Sunstein C. R., ‘Constitutionalism and Secession’, 58(2) The University of Chicago Law Review (1991) p. 633 .

* CSIC - Consejo Superior de Investigaciones Científicas, Institute of Public Goods and Policies (IPP-CCHS), Madrid, Spain.

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