Could a 'Leave' vote in the UK referendum on EU membership be used to extract further concessions from the EU or would the government be bound by the result of the referendum? According to Kieran Laird, principal associate in the public law and regulation team at Gowling WLG, there is no legal bar to a second referendum, and whether the government chooses to follow the precedents will be purely a matter of politics.

Is there any statutory requirement for a second referendum following a vote to leave the EU?

The idea of a second referendum has been floated several times, most recently by Boris Johnson and Michael Howard. Although this time round his enthusiasm has been short lived, Johnson had previously signalled his support for a second referendum when it was put by Dominic Cummings, director of Vote Leave, in June 2015. In fact, Cummings suggested two alternative scenarios in which a second referendum could take place.

The first is grounded in the legal mechanics of the UK's withdrawal from the EU. Under Article 50 of the Treaty on European Union (TEU) the withdrawal process is triggered by the government giving notice of a decision to leave to the European Commission. Following that notice the UK and the EU would attempt to negotiate an agreement regarding the terms of the UK's withdrawal and its future relationship with the EU. Cummings suggested that the government could consider it necessary to put the final form of any such withdrawal agreement to the people in a referendum.

Any decision to hold a referendum on the withdrawal agreement would be a purely political decision-there is no requirement to do so either under the TEU or in domestic law. The European Union Act 2011 (EUA 2011) provides that a referendum must be held before the UK could agree to an amendment of the TEU, the Treaty on the Functioning of the European Union (TFEU) or before the UK could agree to certain decisions to transfer power or competence from the UK to the EU. However, EUA 2011 does not require a referendum on an agreement negotiated under Article 50 TEU.

The second form that a second referendum could take arises where, following a vote to leave, the government does not trigger the Article 50 exit procedure but instead attempts to use that result as leverage to negotiate further concessions from the EU which would then be put to the people in another referendum on whether to leave or remain. Cummings raised this possibility as a way of addressing the problem that a vote to leave may be an unpalatable leap in the dark for many voters, and it is this alternative which Boris Johnson claimed to find attractive.

Again, the decision to hold such a second referendum would be a political one as there is no legal requirement to do so. The European Union Referendum Act 2015 (EURA 2015) deals solely with the single referendum and, were a second referendum to be held, a further Act of Parliament making provision for it would need to be passed by Parliament. This would give eurosceptic MPs on both sides the chance to block a second referendum on the basis that a vote to leave on 23 June 2016 should be determinative.

One of the consequences of the essentially political nature of the debate is that positions are constantly shifting. For example, in The Times on 27 February 2016, Boris Johnson seemed to have abandoned the second referendum idea-at least for the moment.

Could the courts hold that a second referendum must be held?

The courts will not be willing to require a second referendum in circumstances in which the source of that requirement was not found in legislation. In particular, just because a referendum had been held following the government's first deal with the EU, the courts would be unwilling to hold that this gave rise to an expectation-enforceable as a matter of public law-that a referendum would need to be held on a second.

In R (on the application of Wheeler) v Office of the Prime Minister [2008] EWHC 1409 (Admin), [2008] All ER (D) 333 (Jun) a claimant attempted to argue that promises by the Prime Minister to hold a referendum on the first version of what later became the Lisbon Treaty created a legitimate expectation in public law that a referendum would be held on the second version. The High Court rejected that proposition, placing strong emphasis on the fact that under the Political Parties, Elections and Referendums Act 2000 the decision on whether to hold a referendum on a particular issue lies with Parliament. The fact that the claim would involve an interference by the court with the proceedings of Parliament was a 'decisive reason' why it should fail.

The same constitutional reasoning was deployed against (the same) Mr Wheeler-a former UKIP treasurer-when he attempted to argue for a legitimate expectation to hold a referendum on the UK's decision to participate in the Council Framework Decision on the European Arrest Warrant (see Wheeler v Prime Minister [2014] EWHC 3815 (Admin), [2014] All ER (D) 171 (Nov)).

It is therefore clear that, absent an existing statutory requirement to hold a referendum, the essentially political nature of the decision to hold one is such that no court is likely to interfere.

Does the government have a mandate for a second referendum and could it realistically use the June referendum as a springboard to further negotiations?

In its 2015 election manifesto, the Conservative Party stated that it would negotiate new rules with the EU, the result of which would then be put to the British people in a 'straight in-out referendum on our membership of the European Union by the end of 2017'.

Although it sought a mandate for the referendum on 23 June 2016, it did not seek one for a second referendum in any form. But that does not mean that such a referendum could not be held.

The idea of using a referendum result as a basis for renegotiation does of course have precedent in other EU Member States. For example, in 1992 the Danes rejected TEU through which the European Community evolved into the EU, and then later accepted it following some renegotiation by the Danish government.

When, in referendums held in 2005, France and the Netherlands voted against the ratification of the Constitution for Europe, the European Council agreed a mandate for a new Treaty. Subsequent negotiations led to the Lisbon Treaty in December 2007-although neither France nor the Netherlands held a second referendum on the renegotiated deal before ratifying it.

Ireland, however, did hold a referendum on the Lisbon Treaty in June 2008 and the Irish people rejected it. The Irish Government then used that vote to renegotiate the terms of the treaty, securing specific exclusions from certain elements of it which were then presented in a second referendum in October 2009.

There is no legal bar to a second referendum, and whether the government chooses to follow these precedents will be purely a matter of politics. The government has repeatedly stated that there will be no second referendum and, in his statement in the House of Commons on 22 February 2016, the Prime Minister again sought to torpedo the referendum-renegotiation-second referendum idea in response to Boris Johnson's initial public support for it. It may be that the Prime Minister cannot credibly reverse out of that position and, as he has stated that a vote to leave will not trigger his resignation, it is not the case that a successor could follow a different path.

Even were the government willing to return to the negotiating table, the other 27 EU Member States would need to be willing to join them there. There will be a range of factors which make that more or less likely. On the one hand there have been statements from several influential quarters-such as the leader of the largest group in the European Parliament (the centre right EPP group)-that there will be no further negotiation.

However, on the other hand, the recent Greek experience illustrates that the EU is willing to try hard to keep the club together and in a choice between negotiation of a withdrawal agreement under Article 50 and negotiation of a new deal with the UK the latter may prove less unpalatable.

Does EURA 2015 require the government to respect the outcome of the referendum?

There is no provision in EURA 2015 which requires the government to respect the outcome of the vote on 23 June 2016.

This is in contrast to referendums held under EUA 2011, the results of which must be respected. For example, under EUA 2011, s 2, a treaty which amends or replaces TEU and TFEU cannot be ratified unless a majority of those voting in the referendum have been in favour.

Parliament therefore had a clear precedent which it could have used to hold the government to the outcome of the EU referendum but it choose not to do so.

Does this mean that if the UK votes to leave, the government could ignore the result and not give notice to the EU to trigger the withdrawal process under Article 50 of the TEU?

In its 2015 election manifesto, the Conservative Party stated:

[W]e will honour the result of the referendum, whatever the outcome.

That commitment has been reiterated several times, both in and out of Parliament.

However, as the Wheeler case shows, the courts treat such statements made by politicians as existing only in the political sphere and having no legal status. The most recent example of this approach is the decision of the Investigatory Powers Tribunal in Caroline Lucas MP v Security Service [2015] UKIPTrib 14_79-CH, [2015] All ER (D) 104 (Oct). In that case, a promise made in 1966 by then Prime Minister Harold Wilson that the security services would not tap MPs' phone communications was held to be a 'political statement' made in a political context which was never intended to be the ground of legal rights and on which there could be no reliance in law.

Wheeler and Lucas stand in a long line of authority which underlines the fact that the Administrative Court will not pass judgement on decisions which fall squarely within the political realm. The greater the macro-political nature of a decision, the more deference will be given to the decision-maker and the more disinclined the court will be to interfere.

It is hard to think of a more obviously 'political' decision than to take the UK out of the EU. There is therefore no realistic possibility of a court entertaining a challenge to a failure to initiate the withdrawal process under Article 50.

As a matter of politics, however, whether the Prime Minister would maintain any credibility in ignoring a vote to leave is entirely another matter.

Speaking of a second referendum, could the outcome of the UK referendum on EU membership trigger a second referendum on Scottish independence?

There have been various rumblings from the SNP that a vote to leave the EU could trigger a second referendum on Scottish Independence. The SNP leader in Westminster-Angus Robinson-responded to the Prime Minister's statement in the Commons on 22 February 2016 by pointing out that every single Scottish MP, every member of the Scottish Parliament and all but one Scottish MEP support remaining in the EU. Several polls have also shown that a majority of Scottish voters wish to remain in the EU.

Against this background there is a certain attractiveness to the proposition that should the UK vote to leave the EU, Scotland should be given the opportunity to leave the UK. However, it needs to be made clear that, should Scotland leave the UK, it would not automatically be a member of the EU upon independence and would need to apply to join.

Against this background, Nicola Sturgeon has refused to commit to a second referendum on Scottish independence following a vote to leave the EU, but has said that such a result would increase demand for independence. As with many of the issues outlined here, there is no legal requirement requiring or precluding a second referendum on Scottish independence. The decision to call for one will be a political decision for the SNP.

It is worth noting that, from a legal perspective, a second referendum would require the consent of Westminster. Under paragraph 1 of Schedule 5 to the Scotland Act 1998 (SA 1998), the union of the Kingdoms of Scotland and England is a matter reserved to the Westminster Parliament. Prior to the Scottish independence referendum in 2014, an exemption was inserted into SA 1998 which stated that SA 1998, Sch 5, para 1 did not reserve a referendum on Scottish independence where certain requirements were met. One of those requirements was that any such referendum had to be held no later than 31 December 2014. For a second referendum to take place, the Parliament in Westminster would have to approve, by affirmative resolution, an order making a similar exemption to allow for another referendum.

Whether Parliament would feel able to refuse a call for a second referendum in Scotland in circumstances where the UK as a whole voted to leave the EU, but a majority in Scotland voted to remain is therefore a whole other (and wholly political) question.

This article was first published on Lexis®PSL Public Law analysis on 1 March 2016. Click for a free trial of Lexis®PSL.

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