UK Court rules Parliament must approve Brexit notification

November 4, 2016

On Thursday, the UK’s High Court of Justice issued a momentous decision – one that constitutes a dramatic rebuke of the government of Prime Minister Theresa May and, if upheld by the Supreme Court, will greatly complicate its pathway to Brexit. The government had decided it could notify the European Union of the UK’s intension to withdraw without a parliamentary vote, relying instead on its “prerogative powers.” The court ruled in favor of claimants who argued that, because an exit would deprive British citizens of certain rights under European Union law and because the government’s “prerogative powers” can’t be used to change domestic law, the notification requires parliamentary approval.    

Until 2009, the EU had no provision for a member state to withdraw from the Union. But the 2007 Treaty of Lisbon, which took effect in 2009, provided for the first time an exit option. Article 50 of the treaty states that a member state may decide to withdraw “in accordance with its own constitutional requirements.” It goes on to say that a state that decides to withdraw shall notify the European Council, which consists of the heads of state or government of the member states, of its intention, after which the EU, in light of guidelines provided by the council, shall negotiate and conclude an agreement with the state that sets out the arrangements for its withdrawal, taking account of the framework for its future relationship with the EU. It further stipulates that the EU treaties shall cease to apply to the state from the date of entry into force of the withdrawal agreement or, failing that, two years after the notification unless the council unanimously agrees to extend the period.

Although 52 per cent of those voting in the June 23rd UK referendum voted to leave the European Union, a large majority of the House of Commons and a clear majority of the Conservative members supported the Remain option. Indeed, more than 475 of the 650 M.P.s and 185 of the 330 Conservative M.P.s were on record prior to June 23 as supporting the Remain option, along with virtually all of the Labour, Liberal, and Scottish National Party M.P.s. 

Although she supported the Remain option, Theresa May believes her government should abide by the vote in the referendum; as she famously said in July, “Brexit means Brexit.” The problem for the government, of course, was that it was far from certain that, with a working majority of only 15 in the House of Commons, it could carry the day if it put a motion to notify the European Council of the UK’s intention to withdraw to a vote. Such a vote would undoubtedly aggravate the already-considerable division over Europe among the Conservative M.P.s and perhaps even result in a defeat for the government.

The government’s lawyers found an apparent solution to the problem: The government could, they said, dispense with a parliamentary vote and simply use its “prerogative powers” to notify the EU of its intention to withdraw since use of those powers is generally accepted when dealing with international matters. At a marathon meeting in late August, the Cabinet, acting on that advice, decided there was no need for a parliamentary vote prior to notifying the EU of its intention to withdraw. At the annual conference of the Conservative Party in early October, the prime minister announced that it was up to the government and the government alone – not the parliament – to invoke Article 50 and that it would notify the EU of its intention to withdraw no later than by the end of March 2017.

As soon as the outcome of the referendum became known, it was apparent to many that, given the extent of support for the Remain option among Conservative M.P.s and the entire House of Commons and the government’s narrow majority, it would try to sidestep a parliamentary vote.  A number of individuals – Gina Miller, an investment fund manager, Deir Tozetti Dos Santos, a hair stylist, and others – filed claims before the High Court in July arguing that the principle of parliamentary sovereignty and the loss of some rights under European law if the UK leaves the EU required that notification of the intention to withdraw be approved by a vote in parliament. The court heard the arguments in October and agreed with the claimants in its decision Thursday.

The claimants were right for several reasons. For one thing, Article 50 stipulates that a state’s decision to withdraw be made “in accordance with its own constitutional requirements.” A decision supported by 37 per cent of the electorate – 52 per cent of the voters in the referendum supported the Leave alternative and 72 per cent of the electorate participated in it – in a referendum could hardly be regarded, in a state in which parliamentary sovereignty is the bedrock principle of its unwritten constitution, as being “in accordance with its own constitutional requirements.”

For another, Article 50 makes it clear that once the UK notifies the EU of its intention to withdraw, the two-year clock starts ticking. It is quite possible, given the complexity of the many issues that will be involved in the negotiation of the withdrawal agreement, that the UK and the EU may not conclude an agreement within two years. Certainly, all signs indicate it will be a protracted and very difficult negotiation – especially since the ticking clock will give the EU enormous leverage in the negotiation. It is also quite possible that if there is no withdrawal agreement after two years, at least one member of the European Council would object to extending the negotiation. In short, the notification will trigger a process that could result in an exit at the end of the two-year period, even if there is no agreement on the arrangements for the UK’s departure or a framework for its future relationship and the UK achieves none of the objectives it hoped to achieve in the negotiation.   

For many observers, and evidently for the High Court as well, the government’s claim that it could embark on a process that could lead to an exit from the EU on unfavorable terms or no terms at all without the prior approval of parliament, and that doing so was “in accordance with its own constitutional requirements,” defied credulity. It was not at all surprising that the High Court ruled as it did. The only surprise was that the government thought it could finesse the inconvenient problem of obtaining parliamentary support for its decision to notify the EU of its intention to withdraw by resorting to its “prerogative powers.”

Immediately after the High Court decision was announced, the government announced it would appeal to the UK Supreme Court. That court will hear the appeal next month. For the prime minister and her government, Brexit still means Brexit. But the odds are good that, before the government notifies the EU of its intention to withdraw, it will have to obtain the approval of parliament. And that, in a body in which more than 70 per cent of the entire membership and a majority of the governing party supported the Remain option, may be hard to do.


David R. Cameron is a professor of Political Science and the director of the Program in European Union Studies.