The European Court of Justice (ECJ) has ruled that the UK could unilaterally revoke the notice that it gave in 2017 to withdraw from membership of the EU. However, withdrawal would require an Act of Parliament, both to authorise the UK government to revoke the Article 50 notice and to repeal elements of the European Union (Withdrawal) Act 2018 and other legislation that has made a "no deal" Brexit the default outcome of the current Parliamentary process.

If Parliament were to direct the UK government to avoid a "no deal" Brexit, then timing and attention to the detail of existing legislation would be crucial. Failure to achieve the correct sequence of events, and to deal with pro-Brexit provisions built into recent legislation, would mean that the UK would cease to be a member of the EU on expiry of the existing Article 50 notice on 29 March 2019.

The "meaningful vote" on the draft Withdrawal Agreement and Political Declaration scheduled for 11 December is only part of the process required by the European Union (Withdrawal) Act 2018. Even if the government were to secure a vote in favour of the agreement, that resolution would merely pave the way for the Act of Parliament required to implement the deal.

If the draft Withdrawal Agreement and Political Declaration were to be rejected, or if the vote were to be delayed, then the current Article 50 notice would remain inexorably in place until the "exit date" enshrined in the 2018 Act. Rejection or deferral would also leave in place other statutory provisions designed to ensure a 29 March 2019 Brexit, such as section 31 of the Taxation (Cross-Border Trade) Act 2018, which prevents the UK government from entering into any form of customs union with the EU without a full Act of Parliament.

A new Referendum?

The ECJ ruling would allow the UK to withdraw its Article 50 notice, perhaps paving the way for a new referendum to include a "remain" option. However, while there seems to be a growing body of opinion in favour of a new referendum, it does not follow that there would be a clear or cogent Parliamentary majority for any particular form of referendum. For example, pro-Brexit groups might seek to insist that to overturn the 2016 result a new referendum would have to meet minimum turnout criteria, or produce a "remain" vote that exceeds a prescribed threshold, such as a two-thirds majority of votes cast. Pro-remain groups might, by contrast, insist that a simple majority of votes cast ought to determine the result. Given that scope for dispute, it is not clear that a new referendum Bill would have an easy passage through Parliament.It is also not certain that a referendum could be scheduled to take place before 29 March 2019.

Given those issues, revocation of the current Article 50 notice would seem to be the obvious way to buy more time for a fully considered referendum campaign, and also to allow a vote to be scheduled for a time less likely to be subject to winter weather disruption. However, pro-Brexit groups would undoubtedly balk at revocation, arguing that a new "leave" majority would then have to wait for renewed Parliamentary authorisation to serve a fresh Article 50 notice, and a further two years for that notice to expire.

While those arguments play out, the existing statutory provisions tick inexorably towards a "no deal" Brexit.

A general election?

The Fixed Term Parliaments Act 2011 prevents the government from calling an early general election unless there has been:

  • a two-thirds majority vote in the House of Commons
  • or a vote of no confidence, with no alternative government being formed within 14 days.

It is entirely possible that a general election might be precipitated, either by rejection of the draft Withdrawal Deal, or following a conservative party coup based on letters of no confidence sent to the 1922 Committee, or through a more general failure of government (based, for example, on its continuing inability to pass other legislation, including the Finance Bill). In any event, should a general election be called there would be a significant risk of moving towards a "no deal" Brexit. Much would depend on the timing and orderliness (or otherwise) of the election process. 

Once an election is called, Parliament would have very limited time for legislative business before being prorogued and, subsequently, dissolved. Parliament is dissolved 25 working days before a general election. Section 3(5) of the Fixed Term Parliaments Act 2011 defines "working days" as:

any day other than—

  1. a Saturday or Sunday
  2. a Christmas Eve, Christmas Day or Good Friday
  3. a day which is a bank holiday under the Banking and Financial Dealings Act 1971 in any part of the United Kingdom
  4. a day appointed for public thanksgiving or mourning.

In practice, that leaves very little time for an election to be scheduled before 29 March 2019 – the deadline for any UK revocation of the current Article 50 notice. Before dissolution, the fractious nature of the current Parliament would make it difficult to secure passage of the primary legislation that would be required to authorise revocation.

A political agreement would not suffice. For example, the ECJ ruling notes that the EU might agree to extend the Article 50 deadline. However, unless that political agreement were to be reflected in new UK legislation, it would be open to those in favour of a "no deal" Brexit to argue from 29 March 2019 that the terms of the European Union (Withdrawal) Act 2018 prevail, and that the UK's only route to continued EU membership would be a fresh application under Article 49 of the Lisbon Treaty.

Devils and details

The political temperature of the UK means that if the government's draft Withdrawal Agreement and Political Declaration is either expressly rejected, or if the "meaningful vote" is delayed, then pressure is likely to build for either a new referendum or a general election. In either case, avoiding the default position of a "no deal" Brexit would require clear and timely primary legislation. Without that attention to legislative detail, business would have to continue to bear the risk of a "no deal" outcome.