Summary

On 23 June 2016, UK citizens decided that the United Kingdom should not remain a member of the European Union. Thus far, considerable attention has been devoted to assessment of the political and economic effects of the UK leaving the European Union (Brexit). However, much less consideration has been given to the effect that Brexit could have on the United Kingdom’s membership in the other European Community—the European Atomic Energy Community (Euratom).

In Depth

Euratom – An Overview

The Euratom Treaty covers all civil nuclear activities in the European Union. As a nuclear peace treaty, it pools the nuclear industries of its Member States and ensures the security of atomic energy supply in Europe. The general objective of the Treaty is to contribute to the formation and development of Europe’s nuclear industries and to prevent nuclear materials intended for civilian use from being diverted to military use. It applies only to certain entities (Member States, physical persons, and public or private undertakings or institutions) dealing with special fissile materials (e.g., plutonium or uranium), source materials and the ores from which source materials are extracted.

The Euratom Community’s institutional structure is similar to that of the European Union and is built around the same institutional triangle. Fulfilment of the tasks entrusted to the Euratom Community is therefore ensured by the European Parliament, the Commission, the Council, the Court of Justice and the Court of Auditors. Although the Euratom Community and the European Union share the same institutions, the two Communities never actually merged; the Euratom Community has always enjoyed separate legal personality.

The United Kingdom joined the European Atomic Energy Community, the Coal and Steel Community, and the Economic Community in 1973.

Brexit’s Effect on UK Euratom Membership

Despite the fact that the European Union and Euratom constitute separate Communities and the fact that they are governed by different treaties, it is possible that Brexit will, in practice, make it unworkable for the United Kingdom to retain its membership in the Euratom Community. A number of points are necessary to consider in this regard.

First, the UK referendum was only concerned with membership in the European Union and did not extend to Euratom. The referendum question was as follows: “Should the United Kingdom remain a member of the European Union?” Given the United Kingdom’s choice to leave the European Union, the UK government will now have to notify the European Council of such decision. This notification will in turn initiate the exit mechanism pursuant to Article 50 of the Treaty on European Union (TEU), which provides that “any Member State may decide to withdraw from the Union in accordance with its own constitutional requirements”. According to Article 50(3) TEU, the United Kingdom and the European Union will then have two years to negotiate and conclude an agreement setting out the arrangements for withdrawal. If no agreement is reached, the EU Treaties (i.e., TEU and Treaty on the Functioning of the EU only (Article 1 para. 3 TEU)) will cease to apply to the United Kingdom at the end of the two-year period.

The same exit mechanism exists under the Euratom Treaty. Article 106a(1) of the Euratom Treaty provides that Article 50 TEU should also apply to the Euratom Treaty. In this respect, Article 106a(2) states that the reference to “the Union” in Article 50 TEU shall be taken as a reference to the Euratom Community and the Euratom Treaty. As such, if a Member State wishes to leave the Euratom Community, it has to initiate a separate Article 50 TEU procedure. This means that if the UK government formally notifies the European Council of its intention to leave the European Union pursuant to Article 50 TEU, from a legal point of view, that notification would not affect the United Kingdom’s membership in the Euratom Community.

From a UK law perspective, Brexit may be achieved by passing an act (Brexit Act) repealing the European Communities Act 1972 (ECA). The ECA incorporates European law into UK law; it gives legal effect to all rights, powers, liabilities, obligations and restrictions provided for by or under the “Treaties” (including the TEU and the Euratom Treaty). As such, if the ECA is repealed in its entirety, the Euratom Treaty will cease to form part of the UK legal system. This would put the UK in a difficult position—by passing the Brexit Act, the UK government would be unilaterally breaking with its Euratom Treaty obligations. More importantly, this unilateral act would be a matter of domestic law only. It would not constitute the appropriate mechanism for withdrawing from the Euratom Community. In other words, repealing the ECA would have a twofold effect on Euratom: (i) the United Kingdom would have no legal means of giving effect to the Euratom Treaty, and (ii) it would still be bound to fulfil its obligations as a member of the Euratom Community.

This conundrum could in theory be addressed by partially repealing the ECA. If the United Kingdom would like to retain its membership in the Euratom Community following Brexit, the UK government could repeal the ECA only to the extent that it applies to the EU Treaties (i.e., TFEU and TEU), not the Euratom Treaty. It remains to be seen, however, whether this would be politically possible to achieve. The option democratically chosen by the UK electorate is to completely withdraw from the European Union. As such, it would appear to be unconstitutional for the UK government to retain certain EU laws and structures post-Brexit.

The issue is further complicated by the fact that there is a whole set of legal instruments relating to the Euratom Treaty that have been passed by the EU Institutions (e.g., the Nuclear Safety Directive or the Radioactive Waste and Spent Fuel Management Directive). Following Brexit, the United Kingdom’s continued membership in the Euratom Community would give rise to three main issues in this respect: (i) the UK government would have to put in place the necessary transitional provisions to ensure that all existing EU instruments relating to Euratom remain in force in the United Kingdom, (ii) the United Kingdom would have to develop a legal mechanism for incorporating any future regulations or directives relating to Euratom into UK law, and (iii) the United Kingdom’s involvement in preparing and negotiating such regulations and directives would be very (if not completely) limited.

Brexit will also likely have a knock-on effect on the UK court system. Specifically, the Court of Justice of the European Union (CJEU) enjoys unlimited jurisdiction in relation to a number of matters arising from the Euratom Treaty (as set out in Article 144). If the United Kingdom leaves the European Union, UK courts may no longer be bound by CJEU judgments. This could lead to serious divergences in the interpretation of the Euratom Treaty provisions.

Finally, should it transpire that it is in practice impossible for the United Kingdom to retain its membership in the Euratom Community because of Brexit, this may put a question mark over the legitimacy of the UK referendum, which only asked the British voters about EU membership.

Concluding Remarks

It is legally possible for a Member State to leave the European Union without simultaneously withdrawing from the Euratom Community. Indeed, the Euratom Community has a separate legal personality, is governed by a separate treaty and has a separate exit mechanism. However, in the case of the United Kingdom, such a clean split might not be achievable, primarily because the EU treaties and the Euratom Treaty are incorporated into UK law through the ECA. If the United Kingdom repealed the ECA in order to fully withdraw from the European Union, the Euratom Treaty would consequently become unenforceable in the United Kingdom. Even if the ECA is only partially repealed, UK membership in the Euratom Community might simply be unworkable.

As such, one of the unintended effects of Brexit is that, in practice, the “no” vote could make it impossible for the United Kingdom to retain its membership in the Euratom Community.

Michal Kocon, a trainee solicitor, also contributed to this article.