Alan S. Reid, Senior Lecturer in Law, Sheffield Hallam University. The author welcomes comments on the blog at email@example.com
The tumultuous result of the recent EU referendum has seismic implications for the United Kingdom, its constituent parts and of course the European Union itself.
The nature of the future relationship between the UK and the EU, the question of Scottish independence and membership of the EU, increasing calls for unifying Ireland, the risk of Eurosceptic contagion affecting the rest of the EU and the nature, scope and focus of the new 27 member bloc EU are all huge existential questions, the implications of which will reverberate for years to come.
The more immediate legal question to address, and one that has been largely side-lined by the bigger picture problems, is that of the actual process of extricating the UK from the EU legal system.
The process for withdrawal is not without uncertainty. The new process for withdrawal is set out in article 50 of the Treaty on European Union and has only been in force since 2009, when the Treaty of Lisbon came into force. Thus, the process is nascent, without legal precedent and ambiguous.
At this juncture, it is important to set out the historical development of the withdrawal clause.
In the negotiations to create a Constitution for Europe, it was clear that the drafters of the constitution wanted a clear voluntary withdrawal clause, as set out in Article I-60. This was in stark contrast to the previous European Community orthodoxy, namely that withdrawal was politically, legally and practically impossible and as such, the previous treaties did not include a withdrawal clause. Indeed, the main impetus for refusing to acknowledge the possibility of withdrawal, was to effectively ignore any criticism of the drive towards 'an ever closer union' of the Peoples of Europe: see Athanassiou, Edward and Douglas-Scott. The thinking was that to even contemplate the unilateral secession of a member State was to risk this existential danger coming to fruition: the irony is that such thinking may now be forthright in the minds of prominent Bremainers.
Intervening realpolitik crises, such as the Irish rejection of the Treaty of Nice, led to increasing recognition, albeit reluctantly, by the European Community of the growing discontent across European member states with European Union integration. Such acceptance of the emerging reality necessitated the insertion of an exit clause into the proposed Constitution. After the rejection of the Constitution, the withdrawal clause, and indeed most of the major terms of the Constitution itself, were retained in the draft text of the Treaty of European Union proposed at the Inter-Governmental Conference, convened in Lisbon, in 2007.
With the coming into force of the Lisbon Treaty in 2009, the withdrawal clause of Article 50 TEU is now the de facto and de jure process for any member State wishing to exit the new European Union supranational organisation.
However, this has not prevented many hard-line Brexiters claiming that Article 50 is not the only mechanism for extrication. The Vote Leave Roadmap considers that there are three main options for withdrawal. The first method suggested is use of the Article 48 TEU process for changing the treaties of the EU. The second suggestion is the Article 50 TEU process and the final suggestion was to rely on general public international law, specifically article 54 of the Vienna Convention of the Law of Treaties 1969. A fourth possibility also tentatively mooted, is for the UK to simply repeal the European Communities Act 1972 and replace it with new UK law.
The Options - Article 48 TEU
In terms of recourse to the article 48 TEU process, this looks highly improbable (see Armstrong’s analysis). This process is relied upon by Vote Leave as an historical precedent, in relation to Greenland's extrication from the European Economic Community. There are a number of objections to the appropriateness of this mechanism. First, the situation of Greenland in the early 1980s is not analogous to the current situation. Greenland was not a member State of the EEC, it was a constituent country within the Danish Realm, that is it was a semi-autonomous part of the Kingdom of Denmark. After increased self-rule under after the 1979 referendum gave Greenland more autonomy akin to home rule, the Greenland government sought to remove itself from the EEC. Denmark, as the member State of the EEC and desiring to give effect to Greenland's democratic wishes, commenced the process of seeking change to the EEC Treaty in 1982. After a few years of negotiations, EEC law ceased to apply to Greenland by virtue of EEC law: an amendment to the Treaties Thus, the withdrawal of Greenland from the EEC and its laws did not relate to a member State, it only related to the geographical scope of EEC law and the question of access to the EEC single market for Greenland's fish and fish products. Further, after the decision was taken, because Greenland still retained strong legal, political and economic connections with the EEC member State Denmark, Greenland was able to forge itself an EEC identity itself: that of an Associated Overseas Country or Territory.
It will be difficult to argue that the option of gaining Associated Territory is available for either the United Kingdom, since it is a sovereign country that has decided to leave the European Union, or for Scotland, Northern Ireland, London and Gibraltar, as areas of the UK (or as a British Overseas Territory) desirous to remain. Nevertheless, some have suggested that Scotland should consider the option of gaining associated status for the devolved regions of the UK that voted to stay in the EU: the reverse Greenland option. In this latter scenario, the rest of the UK would leave the EU, and the devolved regions of the UK which voted to stay would retain favourable access to the EU internal market as Associated Territories. Such a position would be without precedent, since all Associated Overseas Countries and Territories under EU law retain significant links to a member State of the EU and are all geographically distant from the EU. Nevertheless, the mere fact that this option is being discussed highlights the unique constitutional challenges facing the UK and the EU post-Brexit.
Brexit relates to a member State of the EU voluntarily leaving: something which has no legal or political precedent. From a political perspective, the article 48 TEU process is unappealing to the Brexiters. The process requires the unanimous consent of the governments of the member States and for that decision to be ratified by those member States according to their constitutional arrangements. Thus, there is a danger of the use of a veto by any one of the 27 member States to stymie the process at the EU level and thereafter a risk of a domestic constitutional ratification process of any of the 27 member States delaying or frustrating the process of UK withdrawal. Thus, an ordered, seamless and swift transition of the UK from EU member State to non-EU member State would not be the product of Article 48 TEU. Further, article 48 TEU is now not the only process for dealing with the geographical scope and reach of EU law. Indeed, there is a more specific and more appropriate process under EU law: the Article 50 withdrawal system.
The Article 50 TEU process is more appropriate for a number of reasons. It is the lex specialis for withdrawal of a member State from the EU, whilst Article 48 TEU is the lex generalis for significant changes to any aspect of EU law, including withdrawal of an EU member State. On that legal ground alone, Article 50 should be the most appropriate mechanism. Further, this process only requires a qualified majority decision by the 27 member States, not unanimity and does not require to be ratified by the member States according to their constitutional requirements. Thus, the withdrawal process should be simpler and more streamlined than that of Article 48 TEU. The implications of this process will be set out in a later section.
The Options - Article 54 of the Vienna Convention
It has also been argued that article 54 of the Vienna Convention on the Law of Treaties 1969 applies to the process of UK withdrawal from the EU. Article 54 of the Vienna Convention simply provides that the withdrawal of a party from an international treaty can take place according to two conditions, namely either in conformity with the terms of the Treaty or at any time by consent of all the parties after consulting the rest of the State parties.
Again, like the Greenland situation outlined above, the appropriateness of this mechanism has been severely diminished by the passage of time. The EU now has an explicit withdrawal mechanism (article 50 TEU) and a consultative mechanism for changing the EU Treaties (article 48 TEU). Thus, reliance on the general terms of public international law set out in the 1969 convention would appear incongruous in light of the existence of an explicit process for withdrawal. And indeed, recourse to the article 50 TEU procedure itself would be entirely consistent with the underlying principle behind article 54 of the Vienna Convention, that is withdrawal from a Treaty should take place in conformity with the Treaty and in consultation with the States Parties to the Treaty. Further, a reliance on general principles of international law would fly in the face of the of the well-established legal orthodoxy that confirms the autonomous sui generis nature of EU law. The EU is a new legal order, and as such, amendments to its constitutional foundations must be undertaken according to EU law itself (Defrenne).
The Options - Simple Repeal of the 1972 Act
The other extreme scenario envisaged would be to force through the UK parliament emergency legislation repealing and replacing the European Communities Act 1972. Of course, the UK Parliament is supreme and can enact and repeal any law it so wishes, including those of a constitutional status such as the 1972 Act (see pars 207 of the HS2 judgment), but the legal and political implications of such a premature move would be profoundly destabilising. Without any rules and laws setting out the UK's trading relationship with the EU, premature express repeal of the 1972 Act would create a dangerous legal vacuum, which would also be hugely destabilising politically and economically, particularly as regards the ability of the UK to trade bother within and outwith the European Economic Area.
The last forty three years have seen the UK's laws increasingly adopt a pro-EU stance, using EU law terminology and cross-referencing EU law and EU institutions throughout, in order to give effect to EU law. Further, EU Regulations all have the directly applicable force of law in the UK as well. There are widely divergent views on how much UK law is directly (and indirectly) influenced by EU law, ranging from 15% to 50%, but regardless of the divergence of views on this point, it is an indisputable fact that EU law principles, rules and doctrines have become intertwined and intermeshed with that of the law of the United Kingdom, and its constituent parts of England, Wales, Northern Ireland and Scotland such that, to simply attempt to wind the clock back to 1972 would be highly reckless, difficult and an act of extreme folly. Such action would seriously undermine the reputation of the UK as a modern, outward looking nation state which implements, follows and gives effect to its international law obligations in a spirit of mutual cooperation and respect.
To refuse to use the Article 50 TEU process and to unilaterally refuse to comply with EU law from the date of the express repeal of the 1972 Act, would cause major ramifications at the EU law and international law level. Domestically, since Parliament is sovereign, there is nothing legally to stop the UK Parliament simply repealing the 1972 Act. However, At the EU law and international law levels, diplomatic, political and legal cooperation between the UK, the rest of the EU and indeed international organisations would become fractious, if not impossible, although legal action undertaken by the European Commission or other European Union institutions would be rendered otiose by the UK's lack of engagement with the organisation itself.
The EU could suspend the UK's rights under EU law under Article 7 TEU, but of course if the UK had already unilaterally removed itself from the EU by way of the repeal of the 1972 Act, then a declaration that the UK has been in violation of EU law and thereafter had its rights under EU law suspended by the EU, would be of declaratory value only, from the point of view of domestic law. Similarly, any action by the Commission or any other EU institution at the European Court of Justice would be nugatory, from the view of UK law, given the non-applicability of EU law within the UK legal system, post-Brexit. However, at the EU level, non-compliance would have serious legal implications, including state liability and at the international level, would have important political and diplomatic ramifications.
At the UK level, express repeal of the 1972 Act could only be done through the full legislative procedure of the UK Parliament. This would require Parliamentary consent. Therein lies the rub. The majority of parliamentarians in the present UK Parliament are still in favour of UK membership of the EU, notwithstanding the non-binding result of the recent plebiscite, although the parliamentarians are quick to state their political commitment to respect the wishes of the electorate. However, any attempt to repeal the 1972 Act without invoking Article 50 TEU or without an arrangement in place settling the relationship between the UK and the rest of the EU, would threaten the political commitment to respect the referendum outcome.
The domestic impediments coalesce around the process for replacing the 1972 Act with an act that clarifies the relationship between the UK and the rest of the EU and the domestic law that is potentially in play.
The European Union Act 2011 was enacted by the UK Coalition Government and was designed, in part, to 'make provision about Treaties relating to the European Union.' Primarily, the Act was enacted in order to prevent Euro-creep, that is the perceived increasing land-grab by the European Union, into more and more areas of member State competence. Inadvertently, and according to the law of unintended consequences, this Act may introduce significant complexity into the post-Brexit world.
Section 2 of the European Union Act 2011 provides that any Treaty that amends or replaces the Treaty on European Union or the Treaty on the Functioning of the European Union, can only be ratified if a number of conditions are met. Those requirements are that Parliament must receive a statement on the Treaty amendments, Parliament must approve the Treaty by way of an Act if Parliament and there is a determination that either there needs to be a referendum on the proposed Treaty or that the Treaty changes are not such as to trigger the referendum requirement. These requirements were clearly designed to only operate in the event that new competences, new member States or significantly new institutional structures were to be introduced into the European Union framework and that the UK remained a member State of the EU. If any of these changes were proposed at the EU level, then a referendum would have to take place.
However, it is at least arguable that the terms of the 2011 Act could extend to the new EU treaties that will have to be produced in order to expunge all references to the United Kingdom and all legal effects thereto. The 2011 Act as it currently stands requires direct UK Parliamentary input into proposed changes in EU law. This specific UK law is also bolstered by the general terms of the Constitutional Reform and Governance Act 2010, which requires that international treaties can only be ratified by the UK after being put before the parliamentary approval process, as set out under section 18.
The significance of the 2010 and 2011 acts also extends to the general argument that is gaining traction in the immediate aftermath of Brexit, that is the need for express Parliamentary approval of any changes to the UK-EU relationship. It is indeed true that foreign affairs, that is the power of the UK to ratify international treaties and indeed the power to enter into (and extricate itself from) international relations generally is widely undertaken to be an exercise of the royal prerogative. However, the royal prerogative is a diminishing executive power, subject to ever more control and supervision by the legislative wing of the state. The status quo pertaining to the exercise of the royal prerogative is under attack on two fronts: replacement of the amorphous executive power with a statutorily defined, controlled and exercised power and judicial and democratic supervision of the remaining executive powers of prerogative. The modern interpretation of the exercise of the royal prerogative is that Parliament must be involved in conducting oversight of use of this archaic power.
It has been argued that at the very least, Parliament must be in a position to acquiesce in the exercise of the royal prerogative by the Prime Minister (or other Minister): see for example, Human rights treaties in the English legal system, Bharat Malkani, Public Law 2011 (page 554). Indeed, Lord Oliver, in the International Tin Council case, stated that (at 499F-500C):
“as a matter of the constitutional law of the United Kingdom, the Royal Prerogative, whilst it embraces the making of treaties does not extend to altering the law or conferring rights upon individuals or depriving individuals of rights which they enjoy in domestic law without the intervention of Parliament...”
Clearly this judicial pronouncement refers to the traditional dualist view that international law obligations cannot become a part of the law of the UK unless and until these rights are incorporated into UK law by way of an Act of Parliament. However, the position of the UK post-Brexit reveals the reverse problem: how to 'unincorporate' those international rights guaranteed by EU law, to UK citizens within the UK and the rest of the EU and EU citizens living and working within the UK?
It is submitted that the reverse also holds true: altering the applicable EU law, 'de-conferring' individual EU law rights and depriving EU citizens in the UK of their domestic law rights under UK law must similarly be subject to the intervention of Parliament in order to be legitimate and fully in accordance with the rule of law. Thus, any change to the substantive terms of the 1972 Act, could only be done with the explicit approval of the UK Parliament and could only be done after the terms of UK exit have been agreed with the remainder of the EU.
The Article 50 TEU process
Following the discussion above, if it is accepted that the Article 50 TEU process is indeed the most appropriate mechanism for extricating the UK from the EU, the question of how to do so under this system is no less complex legally than the other processes described above.
Article 50 TEU only extends to just over 250 words. It is rather brief and ambiguous. It states that:
'Any Member State may decide to withdraw from the Union in accordance with its own constitutional requirements.'
It then further provides in 15 words that:
'A Member State which decides to withdraw shall notify the European Council of its intention.'
The first paragraph of Article 50 confirms that the running order of events mirrors the structure of Article 50 TEU itself: There must be an explicit, constitutionally sound decision of the UK to leave the UK before a notification to the European Council can have legal effect (see Mark Elliot’s analysis).
As stated earlier, an unequivocal, explicit intention to leave may well require democratic reflection and input in some form of Parliamentary acquiescence, as the repository of the sovereign will of the people. Further, as has been explicitly stated by numerous commentators, a referendum is not legally binding under the UK's constitutional arrangements. Thus, it is highly likely that such a decision to withdraw will not be forthcoming in the next days and weeks.
This second paragraph of Article 50 is similarly significant because upon receipt of the notification to withdraw, the two year countdown to exit begins to run. It is clear since the weekend that neither David Cameron nor Vote Leave politicians are in no rush to trigger the two year countdown since there is a recognition that once the two year timeframe begins to reduce, the UK's negotiating position on securing a good economic deal between the UK and the rest of the EU becomes seriously weaker. The basis for such a view is that after the two year time limit expires, the UK will exit the EU, with or without a deal on its future relationship with the rest of EU: Article 50 only requires a deal on the terms of withdrawal. Indeed, Article 50 further states that the withdrawal agreement only need take into account the framework for its (the Member State's) future relationship with the Union. This wording implies that if there is no corresponding future relationship agreement already in place, the Member State concerned simply leaves the Union after the two year period, absent such an agreement.
The European Union has clearly been shaken to its core by the seismic Brexit decision. At its heart, the EU is torn between two competing push and pull factors: the desire to act decisively and in a spirt of unity and the requirement to ensure future relations with the UK remain as close as possible. Thus, political statements from the continent have vacillated from the cordial to the hostile, stemming from a desire to show the EU as a unified political bloc that will do everything it can to preserve its position and continued existence (and in so doing punish the UK in order to prevent the collapse of the EU through further defection) and a desire to maintain close diplomatic, political, legal and economic ties with a large European national state (which is significantly in the interest of the European Union).
The European Court of Justice is the arbiter of EU law and has the final word on the interpretation and application of EU law (see Article 19 TEU). As such, only the ECJ can definitively pronounce on the meaning and application of Article 50 TEU.
This can be done through various mechanisms applicable to the ECJ's jurisdiction. For example, if the European Council pressed ahead with a withdrawal arrangement concerning the UK, and the UK considered that a statement by the Prime Minister was not an express statement triggering the Article 50 TEU process, then the legality of these European Council measures could potentially be challenged under Article 263 TFEU.
On the opposite side of the spectrum, were the European Council or the Commission to fail to act in furtherance of the UK's intention to withdraw from the EU, perhaps on the basis that, for a considerable time, the EU institutions were only engaged in informal negotiations with the UK during the pre invocation stage of Article 50, then other Member States and EU institutions could theoretically submit an action for failure to act under Article 265 TFEU. Similarly, post invocation of Article 50, the Commission and the European Council will be in unchartered territory and will be engaged in detailed, complex negotiations with the UK and the other member States of the EU. It is not inconceivable that the negotiations may stall or reach an impasse, and that fact may well encourage other EU institutions or member States to invoke Article 265 TFEU. The basic fact of slow progress in reaching agreement could trigger such an action for failure to act, however a more cynical view would be that the Commission or Council may have been minded to procrastinate during negotiations, clear in the knowledge that the two year deadline is imminent and that the UK will have a weaker hand the closer the negotiations stretch out to the end of the two year deadline.
There is also a possibility that because of the significant divergences in opinion on the legal situation pertaining to the UK's withdrawal, member States in dispute with one another concerning the terms of the UK's withdrawal from the EU, may agree to invoke the dispute mechanism system set out in Article 273 TFEU. However, this procedure is rarely used.
There is also the suggestion that the UK itself, by failing to trigger the Article 50 process in a timely fashion, could be in breach of its good faith obligations under Article 4(3) of the Treaty on European Union, which ultimately could lead to Article 258 proceedings in the ECJ.
More significantly, as the process of disentangling the UK from the EU progresses through the UK parliamentary process, legal issues on the validity, application and the interpretation of EU law may be raised in the domestic courts of the UK. In such circumstances, domestic proceedings may be suspended and the EU law questions referred to the ECJ for adjudication, as per the Article 267 TFEU preliminary ruling procedure. It is also not inconceivable that domestic law issues may arise in the other member States as a result of Brexit, for example Germany might be asked to contribute more to the EU budget. In this situation, Brexit-related Article 267 TEFU references may be submitted to the ECJ from other Member States.
It is supremely ironic that the Leave campaigners' wish to extricate the UK from the European Union may in part depend on clarifications, pronouncements and adjudications emanating from their nemesis, the meddling European Court of Justice.
As regards the domestic situation, there are already legal actions being submitted to the courts of the UK. It has been reported that an application has been made to the Queen's Bench Division of the High Court, concerning the legality of triggering Article 50 TEU without Parliamentary input.
Both of these reported legal developments rest on the use of the royal prerogative to trigger Article 50 TEU. In essence, the argument turns on the triggering process of Article 50 TEU: does this need Parliamentary input or is it sufficient to have the Prime Minister exercise her royal prerogative?
Government lawyers argue that the operation of Article 50 is clearly within the parameters of the royal prerogative. Although factually and politically correct, it is not necessarily legally correct. The argument that the royal prerogative does not fully encompass withdrawal of the UK from the EU, rests on a number of issues surrounding Brexit.
The classic strands of debate on the royal prerogative are based on the works of AV Dicey and Blackstone (See United Kingdom: The Royal Prerogative, T. Poole, Int J Constitutional Law (2010) 8(1): 146-155.doi: 10.1093/icon/mop038 and Activism or Democracy? Judicial Review of Prerogative Powers and Executive Action, Banfield and Flynn, Parliam Aff (2015) 68 (1): 135-153. See further, R (On The Application of Bancoult) v Secretary of State For Foreign and Commonwealth Affairs,  UKHL 61.) At its simplest, the conduct of foreign affairs, as an exercise in diplomacy and international politics, is highly dependent on policy, not law and as such is particularly suited to determination by royal prerogative, notwithstanding current controversies over its use (ie the Chilcot Inquiry).
As stated above, the direction of travel for the UK as a modern 21st Century democratic nation is for the royal prerogative to be steadily reduced over time, via the creation of new statutorily defined and controlled executive powers and for extant royal prerogative powers to be subject to increasing democratic and judicial control. It is this notion that goes to the heart of the legal actions currently being contemplated.
Despite the ambiguity over the exercise of the royal prerogative, it is clear that the royal prerogative cannot be used to change UK statutes (R (On The Application of Bancoult) v Secretary of State For Foreign and Commonwealth Affairs,  UKHL 61, at para 44). Thus, the royal preogative cannot be used to change the European Communities Act 1972: only a new Act of Parliament can repeal and replace the 1972 Act. The controversy concerns how this is to be done.
The view of Government lawyers would, in all likelihood, be that the process would be as follows: the Prime Minister triggers Article 50 TEU and Whitehall begins the negotiations with the EU and its Member States. Both of these events are an exercise of the royal prerogative. After this process has ended, Parliament is involved: draft Acts of Parliament are created, setting out the mechanism for repeal of the 1972 Act, addressing the UK's relationship with the EU and creating powers for the UK to conduct trade with the rest of the world. This view assumes an orderly, timely and neat process and from that context, it is highly unrealistic. In particular, the two year time limit for Article 50 negotiations is extremely short and it is likely that the UK would desire to extend this timeframe, particularly in the event that there had been scant pre-Article 50 informal negotiations with the EU.
For the argument that the royal prerogative is not appropriate for triggering Article 50 TEU, there are a number of points that can be raised in support of this proposition.
First, the royal prerogative, in its classic exposition, is mainly concerned with the making of treaties. The unmaking of treaties is never really addressed in the textbooks and in the journal articles. This omission is important for a number of practical reasons.
First, the emphasis on making treaties is entirely warranted and it is easy from this perspective to see why and to understand how the prerogative works. When desiring to enter a treaty regime under international law, it would be unwieldy and cumbersome for the relevant Minister and civil servants to have to request Parliamentary approval every time they wished to engage in international negotiations. Once negotiations at the international plane have concluded, Parliament is involved through the passing of legislation taking the UK into the treaty regime. Indeed, this is exactly what happened in 1972: The UK negotiated the terms of its entry into the EEC and the Treaty of Accession was signed on the 22nd of January 1972; Parliament was given the opportunity to discuss the terms of the Treaty of Accession under the Ponsonby rule and also debated the terms of the European Communities Bill, which became the 1972 Act and the UK joined the EEC on the 1st of January 1973. It is established UK practice that the United Kingdom Parliament will enact domestic law giving effect to the terms of the international treaty in readiness of ratification of the treaty.
During the course of the past month, three main ways to trigger Article 50 TEU have been mooted. The first method suggested is the classical method outlined above, namely the simple exercise of the royal prerogative, exercised by the Prime Minister. The second suggestion is that propounded by Nick Barber, Tom Hickman and Jeff King. They suggest that the significance of the decision to trigger Article 50 TEU, which will ultimately repeal the 1972 Act, requires an equal level of Parliamentary input and as such this can only be provided through an act of Parliament authorising the Prime Minister to trigger Article 50 TEU.
Adam Tucker has suggested that there is a third way, namely the making of an Order in Council under section 2(2) of the 1972 Act.
Each of these possibilities throws up immense constitutional challenges. The third option, use of the Order in Council mechanism under the 1972 Act, is controversial because the system envisaged under section 2(2) was designed to allow the UK to pass secondary legislation, in order to give effect to EU obligations and exercise EU Treaty rights. Although it is true that the use of Article 50 TEU would come under an expansive view of exercising EU law rights, it is more realistic to adopt a narrower view of section 2(2) of the 1972 Act such that it can only relate to positive EU law obligations, rights and duties and not the negative right to extricate the UK from the entire EU edifice.
Of course the use of Article 50 TEU relates to EU law, but it is the definitive step in releasing the UK from the EU and thus the terminology used in section 2(2) was highly unlikely to have been contemplated by the drafters of the Act in 1972 as encompassing acts taken to withdraw from the EU, especially since the right to withdraw from the EU has only existed for seven years. Nevertheless, it is an intriguing argument that, on one level, actually accords more fully with the EU's own view of the EU legal system, as a sui generis legal system. Thus, having to use the 1972 Act to withdraw from the EU, rather than resorting to general principles of UK constitutional law, appears more consonant with the view that the EU is a unique legal system, requiring special measures of withdrawal. It would also be neater in a sense, in that it would be internally consistent: the processes under the 1972 Act would be used to commence unravelling the 1972 Act.
The second option, that of requiring the Prime Minister to seek Parliamentary approval for triggering Article 50 is similarly attractive, but problematic. It is attractive to require an Act of Parliament to authorise use of Article 50 TEU because it ensures a high level of democratic control and scrutiny will be undertaken before the UK starts the process of withdrawing from the EU. This is fundamentally important because the referendum result was so divisive for the country and did not show an overwhelming desire to leave. Rather, just slightly over half of the population voting chose to leave the EU. The referendum result is not legally binding since there is no mention of the legal effects of the referendum in the authorising legislation of 2015. Further, it became acutely clear after the referendum, that the preparations for a Leave win, were virtually non-existent and that certain statements by the Leave campaign, and indeed Remain, were, at the very least, economical with the truth. The bigger question surrounds the post-EU environment for the United Kingdom and this question was never put to the electorate - what kind of relationship with the EU should the UK have?
It has been argued that there are seven different options available to the UK for a life outside the EU, all with vastly different outcomes. These options range from close cooperation with the EU as an associate member, membership of the EEA or EFTA, bilateral cooperation with the EU, a customs union with the EU, a free trade arrangement with the EU or simple WTO membership. Clearly, this complexity in post-EU relations was inadequately addressed during the referendum campaign and the answer to this question was not given when 52% of those voting answered 'leave the EU' in the referendum. Thus, there is no definitive UK-wide answer to this question, such that the Prime Minister cannot simply state that the express will of the people is clear.
In such circumstances, an expanded role for the UK parliament becomes very attractive: once the settled will of the people has been 'discovered' regarding the preferred post-Brexit choice, the Prime Minister can trigger Article 50 TEU and then deploy negotiators to spend the next two years securing a deal to achieve this settled will.
However desirable a new Act of Parliament authorising the Article 50 trigger would be, this approach fatally undermines the established process of the exercise of royal prerogative and confuses the beginning and the end of the withdrawal process. The Article 50 TEU process only commences the process for exiting the EU, and the UK Parliament will get its say when the Bill authorising the repeal of the 1972 Act is introduced to the House of Commons.
Thus, it appears that the most likely outcome is for the royal prerogative to be used by the Prime Minister to trigger the Article 50 TEU process. Nevertheless, this process is hardly satisfactory. The primary concern is that the two year limit is incredibly short and if there are seven options on the table for the status of the UK post-EU, most of this time may be taken up with attempting to secure the 'wrong' type of withdrawal agreement, if no clear exit strategy is in place.
An issue related to this is the status of the currently constituted rights of UK and EU citizens post-Brexit. This question also highlights the unprecedented nature of the task facing the UK.
Unmaking a treaty has been only sporadically undertaken in the history of the UK. It has to be stressed that withdrawal or denunciation of a Treaty is often a last resort and is usually a result of other party non-compliance or because of a material change of circumstances. Indeed, the UK does not enter international treaties lightly and accedes to treaties in good faith, observing the international law principle of pacta sunt servanda. Generally, stable, democratic and internationally respected sovereign states only rarely denounce international treaties.
Withdrawing from or denouncing a 'traditional' treaty is a relatively simple process, utilising the royal prerogative. International treaties commonly provide that withdrawal or denunciation can be activated by simple notification of this intention by the member state to the depositary state or international organisation. The treaty would then not apply to the state concerned after a set period of time had elapsed, for example six months or a year. Some treaties may also impose certain conditions, such as the expiry of a certain period before withdrawal can be activated and treaties may provide for the legal effects of the treaty subsisting for a period beyond the withdrawal (see Article 58 ECHR). The nature of the international agreement is also a factor pointing to the ease of withdrawal. In the case of bilateral treaties, invariably they only encompass agreement on a narrow field of state action, such as trade, joint construction or projects (such as the Concorde) or financial cooperation. In the case of multilateral treaties, they predominantly tend to be restricted to dealing with a narrow range of legal fields. Again, removal from such a treaty only involves a narrow number of legal issues in the domestic plane and the issues would be more directed at the international law field.
In all of these instances, the process is solely in the hands of the departing state. Once triggered by royal prerogative, the domestic legal process is simply for an Act of Parliament to be passed (assuming of course that the international treaty had been given legal effect in the UK) extricating the UK from the treaty regime concerned. The Act of Parliament will provide for removal from the regime. Said removal from the treaty regime is normally straightforward, since the international rules applicable will primarily relate to the rules between nations and will relate to the financial costs of withdrawal, the loss of rights within the international organisation and the removal of jurisdiction to oversee compliance with the international regime. In these circumstances, exercise of the royal prerogative simpliciter is absolutely appropriate: the statement to withdraw is made under the royal prerogative, is transmitted to the depositary state/international organisation, that organisation/state informs the other parties of that fact and after the requisite time period has elapsed, the state is deemed to have left, whilst Parliament, after the exercise of the royal prerogative, gives royal assent to the domestic bill negating the legal effects (if any) within the domestic legal plane. These examples all share one common theme: the international organisation or depositary state plays an entirely passive role in the withdrawal process.
The extraction of the UK from the EU is of an altogether greater magnitude, requiring constitutional changes in the UK, institutional changes for the EU, changes to the running costs, operation and composition of the EU and the impact of directly effective EU law within the UK.
This process for exiting the EU, by contrast to traditional international law processes, is driven by the EU itself, and must be conducted according to EU law, not general public international law. The suprantional sui generis nature of the EU requires that the EU be actively involved in the process for withdrawal of a Member State. Further, from a more practical standpoint, the close cooperation, integration and enforcement mechanisms that inhere under a supranational governance system, necessitates that the EU institutions must play a large part in the withdrawal process, for the decision to withdraw does not result in a simple binary result: the member State becomes a non-member State with no legal connections. Rather, the EU actively seeks a continuing relationship with the exiting Member State. Again, in a traditional multilateral treaty system, the fact that a Contracting State exits has minimal impact upon the international intergovernmental supervisory organisation system itself: the Contracting State, by leaving, loses voting and participation rights and the intergovernmental supervisory organisation simply carries on without the State concerned. Further, the decision to leave a multilateral treaty does result in a binary position: from the day after exit, the Contracting State has no legal connection to the treaty regime (except for the possibility for continuing liability for prior acts).
Article 50 TEU requires a withdrawal arrangement to be agreed within two years. The sheer scale of the changes required will require massive cross cutting legislative changes within the UK, such that it is submitted, simple triggering of Article 50 TEU is inappropriate.
Thus, if the two alternative processes outlined above are ill-suited to UK removal, as a matter of UK law, then can it be that the unique characteristics of the Brexit case require modifications to the royal prerogative system itself? Could some sort of 'enhanced' royal prerogative/royal prerogative be required? Young has suggested that a new constitutional convention can crystallise, requiring that in areas of extreme high policy, it has to be shown that future planning and a clear exit strategy has been completed and agreed by the sovereign Parliament before the royal prerogative can be exercised. Further, it also appears reasonable that the royal prerogative, when being used to initiate a bilateral process of negotiation, should only be activated when the terms of reference are clearly delimited.
Regardless of the merits and demerits of the three options above, it is clear that the United Kingdom is in novel constitutional waters. Whatever process is ultimately adopted to begin the formal process of exit, for political and legal certainty, there needs to be a road map setting out the future direction of the UK's relationship towards its nearest neighbours on the continent of Europe. After the path to exit is made clear, the Article 50 process should progress. To fail to do this, risks an internecine war between the UK and EU which is no-one's long term interests.
The tumultuous events in the UK in the last month have plunged the UK and the EU into turmoil. In these times of immense uncertainty, only one thing is certain; the end of the UK's membership of the European Union is only just beginning.
Photo credit: Metro.co.uk