‘Brexit’, Article 50 TEU and the Constitutional Significance of the UK Referendum

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This post tries to answer two questions:

First, who has the right to trigger the process of Article 50 TEU under the UK constitution? Second, what is constitutional significance of the UK referendum?

Article 50 TEU is the provision that governs the process of withdrawal of an existing EU Member State from the Union. The provision was introduced by the Treaty of Lisbon and it has not been used thus far. This provision is drafted in a way that is not too prescriptive with the clear intention for allowing a considerable margin for manoeuvring in the ensuing negotiations.

Article 50 (1) stipulates that a Member State may decide to withdraw from the Union in accordance with its own constitutional requirements whereas Article 50 (2) provides that the relevant Member State must notify its intention to the European Council.

It is clear that once the process of Article 50 begins, the negotiating position of the Union is strengthened. This is because Article 50 (3) TEU imposes a time frame for the completion of negotiations (two years). If at the end of this period the EU and the Member State fail to reach an agreement, the Treaties cease to apply to that Member State thus leading to a disorderly withdrawal. The two year period may be extended by the European Council acting unanimously. Since the costs of a disorderly withdrawal are apparently higher for the Member State that leaves the Union, it is obvious that the two year time-frame hangs like a sword of Damocles over its shoulders. This means that the question of when the process begins and on whose initiative is critical.

The ‘who’ and ‘when’ under the UK Constitutional Arrangements Regarding the Invocation of Article 50 TEU

The question of who has the power to trigger Article 50 TEU has attracted a deserved amount of attention by scholars and commentators. Most of the scholars agree that EU partners cannot trigger the withdrawal process (see for example Marl Elliott, Sionaidh Douglas-Scott, Nick Barber, Tom Hickman and Jeff King).

This is certainly the case from a legal point of view however, it is possible for the EU to increase the pressure on the UK to trigger the renegotiation process. How? By signalling, in the form of statements or leaks that intensify the uncertainty regarding the terms of the endgame, particularly concerning the UK access –or the degree of access- to the single market. The prolongation of the period before the formal notification under Article 50 is useful for the UK only if there is no market volatility. Otherwise, the UK would be incentivised to move faster.

Although it is clear that the initiative for triggering Article 50 lies with the Member State that decides to withdraw, there are different views about ‘who’ in that Member State can actually take this decision. Scholars agree that the process of withdrawal cannot be triggered by the referendum itself.

There are four strands of thought (with some variations within each strand):

  1. The first argues that it is the Government who has the power to invoke Article 50 on the basis of its “prerogative powers”, namely the assemblage of executive powers without statutory underpinning that were held originally by the Monarch and in modern times are exercised by the Government particularly, but not only, in the field of international affairs (see for example Marl Elliott, Carl Gardner and David Allen Green)
  2. The second view argues the Government cannot invoke Article 50 without the prior authorisation of Parliament. In other words, the decision to notify the European Council must have statutory underpinning (see Nick Barber, Tom Hickman and Jeff King)
  3. The third view advocated by Adam Tucker is that Article 50 can be invoked by the Government but not on the basis of its prerogative powers; Tucker argues that there is already a statutory basis (section 2 (2) of the European Communities Act (ECA) 1972). Furthermore, Tucker argues that this statutory legal basis supersedes the overlapping prerogative powers (as per Attorney-General Appellant v De Keyser’s Royal Hotel)
  4. The fourth view advocated by Alisson Young is that there is a constitutional convention that requires the involvement of Parliament before the triggering Article 50 TEU.

I concur with the view that the Government has the power to invoke Article 50 TEU based on the prerogative even though other paths that involve Parliament at an early stage are legally possible and desirable. I proceed by explaining briefly why in my view the very interesting propositions by Nick Barber, Tom Hickman and Jeff King, Adam Tucker and finally Alison Young are not entirely convincing.

Firstly, Barber, Hickman and King point out that the process of Article 50 leads irrevocably to the nullification of existing EU law rights of UK citizens either as a result of a renegotiated deal or through the lapse of the two year time-frame without an agreement. They argue (on the basis of Case of Proclamations and R v. Secretary of State for the Home Department (ex parte Fire Brigades Union and others)) that the prerogative powers of Government cannot instigate a process that leads to the nullification of statutory rights. According to them, the opposite proposition would render the ECA and other Acts of Parliament (for example the European Parliamentary Elections Act 2002) nugatory.

I believe that this position, interesting as it may be, can be questioned on two points. To begin with, even if we assume that the invocation of Article 50 TEU alone through the exercise of prerogative powers has as a direct consequence the alteration or nullification of statutory rights (which is still a moot point), I believe that it would not go against the common law authorities used by the authors because in this case the exercise of the prerogative powers simply acts upon a clear mandate of the electorate contained in the referendum.

It is at this point that I believe the constitutional significance of the referendum becomes evident. In the Case of Proclamations and Fire Brigades Union, the common law has drawn the line between the arbitrary use of executive power by the government on the one hand, and the expressed will of Parliament on the other. The rationale of these cases is clear: to give preference to the will of the body which is closest to the ultimate political legitimising factor of the UK constitutional arrangement, the democratic principle. The difference in our case is that the exercise of the prerogative powers of government is not arbitrary but in line with the democratic principle; in fact, it acts upon a clear mandate from the demos.

Furthermore, I do not think that involving the Parliament in the way suggested by the three authors would have any meaningful effect (apart from perhaps a symbolic endorsement of the referendum result by Parliament). Unless parliamentary involvement means repealing the ECA before the invocation of Article 50 –and the authors do not argue for this- I do not see how a formal parliamentary authorisation to trigger this provision would avoid a situation where the ECA 1972 or the European Parliamentary Elections Act 2002 are rendered nugatory if the two year period lapses without agreement (this is one of the arguments they put forward in order to explain why prior Parliamentary authorisation is necessary). I think it self-evident that the repeal of the ECA 1972 before the triggering of Article 50 TEU or before an agreement with the EU would constitute a unilateral act that would taint, if not completely torpedo, the negotiation process.

Let me now turn to the view put forward by Adam Tucker. Tucker argues that  Article 50 can be invoked by the Government only on the basis of section 2 (2) ECA 1972 because this provision supersedes the overlapping prerogative powers (as per Attorney-General Appellant v De Keyser’s Royal Hotel). He argues that this interpretation is preferable because it is legally sound and allows for Parliamentary scrutiny when the actual decision for triggering Article 50 is made. Although I agree that some involvement of Parliament in the early stages –i.e. before the actual invocation of Article 50- is legally possible and perhaps politically desirable, I am not entirely convinced that it provides the only lawful course of action (i.e. excluding completely the possibility of using prerogative powers).

According to Tucker section 2(2) ECA enables Ministers to:

make provision (a) for the purpose of […] enabling rights enjoyed or to be enjoyed by the United Kingdom under or by virtue of the Treaties to be exercised

Tucker argues that based on Article 50 TEU the United Kingdom has two new rights namely, the right to pursue on orderly withdrawal and the right to withdraw unilaterally. The decision to use these rights can be made on the basis of section 2(2). If this is the case, then the statutory base supersedes the overlapping prerogative power in this area of foreign affairs. What’s more, the decision must follow the requirements and formalities that govern the relevant statutory power.

Tucker puts forward an elegant proposition however I believe that it requires closer scrutiny.

If one examines section 2(2) and its position within the ECA architecture it becomes clear that its purpose is to enable the Government to adopt secondary legislation in order to implement EU rules that are not directly applicable, for example the rules contained in Directives (a view also echoed by Mark Elliott). This of course does not prevent the use of this provision in the way suggested by Tucker –namely to function as a vehicle to introduce a level of parliamentary scrutiny of the decision of the Government to trigger Article 50. However in my mind this possibility does not mean that section 2(2) has superseded or set aside the prerogative of government in this area of foreign affairs.

Taking this contextual analysis of section 2(2) further I believe that one needs to identify other possible provisions that might help with the ‘triangulation’ of the interpretation of section 2(2). The other provision that is relevant is section 2(1). Whereas the purpose of section 2(2) is the facilitation of the adoption of secondary legislation for the implementation of not directly applicable rights in the national legal order, the purpose of section 2(1) is to govern the way in which directly applicable provisions like those of the Treaties become part of the domestic legal order.

Section 2.1 reads:

All such rights, powers, liabilities, obligations and restrictions from time to time created or arising by or under the Treaties […] as in accordance with the Treaties are without further enactment to be given legal effect or used in the United Kingdom […]

This provision particularly the part that refers to “[…] restrictions from time to time created or arising by or under the Treaties” which are to be given legal effect without any further enactment could be interpreted as acknowledging the existence of an appropriate and adequate space which facilitates the use of prerogative powers to trigger Article 50 even if this essentially starts a process that leads to restrictions –in this case the possibility of ending of the application of the Treaties on the UK-that arise by the Treaty (in this case Article 50 (2) and (3)).

I believe that such a contextual interpretation of section 2(1) complies with the purpose of this provision within the ECA architecture:  to function as the legal vehicle that connects the two legal orders by introducing a degree of “automaticity” for some (directly applicable rights, obligations and restrictions) but not all elements.

Furthermore even if one accepts Tucker’s view that section 2(2) supersedes the overlapping prerogative one point remains unresolved. What is the extent of the overlap? Does it include instances where the decisions need to be taken in an expeditious fashion because of the fast changing political and economic environment? I think that the answer can only be negative. In other words, I believe that even if Tucker’s position is correct namely, that the Government has to use the statutory basis of section 2(2) in order to trigger Article 50, this duty reaches its limit in instances where the government can argue that there is a need for expeditious response to changing political, economic or financial circumstances in which case the possibility to resort to the prerogative remains intact. This is particularly relevant in the case of the renegotiation of UK’s relation with the EU where the whole process affects and is affected by the economic, financial and political environment.

This last observation is linked with another issue: Could it be argued that the prerogative powers of Government in this area have been curtailed not by statute (as Tucker argues) but by constitutional convention?

It has been suggested by Sionaidh Douglas-Scot that a growing constitutional convention requires that prerogative powers be subject to parliamentary approval as evidenced by the Commons vote against military action in Syria in 2013. Although I share the view (see Gavin Phillipson) that a constitutional convention for Parliamentary approval exists in the case of the deployment of troops abroad or the use of force, I do not believe that such convention covers all aspects of international affairs such as the Treaty making/concluding power of the Government. In fact, even within the specific topic of the use of military action, the existence of such convention is debated (see the statement by the Secretary of State for Defence)  and in any case it is not clear how wide this convention is, namely what instances of military activity it covers (special forces operations; training of foreign troops; full-fledged military engagement etc) and what type of Parliamentary involvement it entails (debate in Parliament; Parliamentary vote for approving military action; before or after troop deployment etc).

Despite the above, Alisson Young proposes to use the aforementioned convention by analogy. Young’s argument is that both the use of force and the initiation of the process that would change the relationship between the UK with the EU involve decisions with significant political (and/or constitutional) repercussions, they both relate to sovereignty and both concern issues in which the public is emotionally involved. Young argues that because of these reasons, a convention emerges by analogy requiring the Parliament to be given “the opportunity to debate” the matter.

Although I believe that a parliamentary debate prior to the invocation of Article 50 would be useful particularly since, as Young rightly points out, despite the referendum result there is no consensus regarding the content of the negotiating position of the UK, this does not mean that such deliberation is constitutionally necessary for triggering Article 50.

Firstly, I find it difficult to see how a convention can be created or recognised by analogy as a matter of principle. As already mentioned, I see good reasons why Parliament should be involved but that does not mean that a convention that limits the prerogative Powers of Government exists in this case.

Even if we were to accept that such convention existed by analogy, the latter would not cover circumstances of emergency (See the Cabinet Manual Chapter 5, para. 5.38) or instances where expeditious action is required. For example, I think it would be difficult to argue that such a convention limits the power of government to act swiftly in response to market volatility –due to prolonged uncertainty- that could harm the economy. Obviously in the case of the invocation of Article 50 TEU the need to ensure the ability of the Government to respond quickly is of a different kind compared with the case of military action where the element of surprise is important in providing a tactical advantage. By contrast, in the case of the invocation of Article 50 TEU it is important for the government to be able to act fast in a changing political, economic and financial environment with the aim to limit uncertainty. This uncertainty might be fuelled by prolonged debates in Parliament about the “when”, the “how” and the “what” of the invocation of Article 50 TFEU. An opportunity for Parliament to debate the negotiating position of the government would be welcome but not necessary from a constitutional point of view.

If we were to recognise an emerging convention, that would be the expectation by the Government (and possibly all other constitutional actors including the Parliament itself) to respect the result of a referendum that was carried out in accordance with the UK Constitution (in this case on the basis of the European Union Referendum Act 2015 adopted by an overwhelming majority in Parliament). It is precisely because of the direct involvement of the demos that the triggering of Article 50 by means of prerogative powers is not arbitrary and legitimised in a way that the military action in Syria was not. Here too we see a manifestation of the constitutional significance of the referendum.

Concluding Thoughts

I believe that the UK Constitution -which has not ceased to be flexible and political overnight- allows for various constitutional courses of action regarding the process for the invocation of Article 50 TEU. One of them is certainly the use of prerogative powers of Government. Secondly, the constitutional significance of the referendum vote consists in the fact that the decision of the Government to trigger Article 50 TEU is not arbitrary but in effect, it acts upon and implements the expressed will of the demos.

This does not mean that the involvement of Parliament at an early stage in the process is not desirable, quite the contrary. In other words, a debate in Parliament would be appropriate but it would not be necessary from a constitutional point of view.

The preceding analysis discusses the existing constitutional margin for manoeuvring but it is very clear that the next steps for determining the UK’s relationship with the EU would be governed by political considerations. The parties have incentives for reaching some compromise but this does not mean that the negotiation process will be problem free.

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Martin Holterman says

July 8, 2016

I've been thinking that Part 2 of the Constitutional Reform and Governance Act 2010 - which deals with ratification of treaties - should be applied by analogy to withdrawal from (multilateral) treaties. In that case, the rule would be that the art. 50 notification letter has to be laid before Parliament for 21 sitting days before it can be sent.

Aris Georgopoulos says

July 9, 2016

Very interesting observation indeed. The UK follows by and large the dualist tradition regarding the relationship between domestic and international Law. This means that international law obligations that the UK Government has undertaken (which exist within the sphere of international law) have to be ‘internalised’, ‘transposed’ within the domestic legal order by Parliament.
Section 20 et seq. of the Constitutional Reform and Government Act 2010 refer to the process of ‘internalisation’, of the international commitments in the domestic legal order. They do not affect the prerogative powers of Government to engage in treaty making at the international law level.
In addition in the case of the invocation of Article 50 there is no new Treaty involved. In fact the European Union Act 2011 reiterates (section 18): ‘Directly applicable or directly effective EU law (that is, the rights, powers, liabilities, obligations, restrictions, remedies and procedures referred to in section 2(1) of the European Communities Act 1972) falls to be recognised and available in law in the United Kingdom only by virtue of that Act or where it is required to be recognised and available in law by virtue of any other Act.
Article 50 TEU is such a provision.
Furthermore our discussion does not take place in the context of a capricious, arbitrary decision of the Government to leave the EU. In such a case the arguments for the necessity for the involvement of Parliament would have been stronger. Instead here the Government essentially implements the result of the referendum (in other words its decision to trigger Article 50 is not arbitrary and it has democratic legitimisation).

Of course the government may decide to discuss its intention to trigger Article 50 TEU (including the timing of such action). I believe that unless there are reasons to act fast (responding to economic, political circumstances) such would be the preferable course of action. However from a legal point of view it is one of the various options and not the only option.

James Nolan says

July 18, 2016

The phrase "unless there are reasons to act fast..." prompts me to share the Discussion Paper below. Precipitate action following upon the Brexit referendum may already be having unintended consequences.

UK separation from the EU should not imply loss of the world’s most useful language.
By James Nolan, JD, AIIC, ACI
Deputy Director, Interpretation, Meetings & Publishing Division, United Nations (ret)
Head of Linguistic Services, International Tribunal for the Law of the Sea (ret)


As a member of AIIC and an Auxiliary Conference Interpreter with the EU, I have received an invitation to the General Assembly of EP Permanent and Temporary Staff Interpreters on 6 July 2016 but I will be unable to attend because I am not in Brussels. However, wishing to offer some input into the discussion of the recent UK vote on separation from the EU, I submit this discussion paper.
The EU is reportedly urging the UK to complete withdrawal procedures expeditiously in order to minimize disruption. Meanwhile, there is speculation that English will cease to be an official EU language. That would be a misfortune for both the EU and the world.
Britain has no monopoly on the English language, which is part of the world’s cultural heritage, spoken as a first or second language by some 850 million people. I cannot help recalling that on the occasions when I have been privileged to work for the EU, training interpreters in the EU Rule of Law Mission in Kosovo organized by the Civilian Office, European Union Special Representative (September, 2009) and interpreting at the 67th EU/US Inter-parliamentary Meeting in Washington D.C. & New York (December, 2009), the language I used was Standard English and knowledge of the dialect or accent of the British Isles was irrelevant.
Regardless of whether England remains a member country, the EU needs English in order to remain what it is today: “one of the greatest economic and political achievements of modern times” in the words of President Obama, an intergovernmental organization of global stature representing the values and ideals of European culture, an economic power comparable to the US, and a cornerstone of world order second only to the UN.
With the one member less, the EU will remain all of these things but the burdens on the remaining members will be heavier and it would be unrealistic and unfair to ask Ireland or Malta to shoulder the responsibility for the continued use of English when that position could place them at odds with the survival of their own national languages.
That is how the question appears from a political point of view and it will no doubt be resolved by negotiation.
However, the question from a technical-linguistic point of view is somewhat different. English needs to be maintained among the EU languages not out of deference to any particular sovereign state but because for historical reasons it happens to be today’s global lingua franca, the nearest thing the world now has to a universal language, and hence an invaluable tool of communication, and an indispensable pivot language in simultaneous interpretation into other languages. That being so, it is pointless to expect English-speaking EU linguists to belong to a particular nationality, especially in view of the fact that nationality is per se a suspect classification in most legal contexts because it lends itself to misuse. More importantly, it would be counterproductive from the standpoint of interpretation quality.
Interpreting is a form of public speaking, and interpreting for international fora, with participants coming from many different nations and cultures and the output being recorded and eventually broadcast online worldwide, is a form of acting on the world stage. Above all else, what is expected of interpreters by an international audience, and by the other interpreters who may be taking relay into other languages, especially if one’s target language is a lingua franca like English, is clarity. This means cultivating a relatively neutral style of speech unencumbered by strong accents or regionalisms. In this regard, there is no better advice than that offered by a great actress and acting teacher, Uta Hagen:
“Hamlet’s advice to the players, ‘Speak the speech, I pray you, as I pronounced it to you, trippingly on the tongue,’ does not make much sense when delivered with New Yorkese distortions. We have heard the comic overtones, the disservice done to the poetry of Christopher Fry and T. S. Eliot, to the tirades of Shaw by drawls and twangs and slurs. Nor is British speech the answer. It places Chekhov, Ibsen, Strindberg or Molière in the heart of England. British speech belongs to our colleagues abroad. If it is demanded by a specific character or the milieu of the play, it can be learned with the relative ease with which other dialects or accents are learned for particular roles.” [Hagen, Uta. A Challenge for the Actor. Scribner, New York, 1991. P. 39.]

With or without England, Europe needs English.