Stopping Brexit is possible, but it’s complicated. I’m not arguing here that no Brexit is going to happen, only that it is legally and practically possible, and recent events render it slightly more likely.
The only way Brexit can be stopped is if the Article 50 notification, triggered in March 2017 to begin the UK’s departure from the EU, is revoked. Under EU law, once Article 50 is triggered, the departing state automatically leaves the EU after two years, unless Article 50 is extended.
Unfortunately, the short text of Article 50 doesn’t say whether the departing state can unilaterally revoke its notification to leave, or whether the consent of the remaining EU member states is required.
The European Court of Justice (CJEU) was asked to rule on this very question. On December 10, it found that a country could unilaterally revoke Article 50, and that it would be able to remain in the EU on its current membership terms. The ruling emphasised that if a country chose to revoke the notification, this would reflect its “sovereign decision” to do so. This means the UK would be able to revoke Article 50 unilaterally, without the agreement of the rest of the EU.
Changes needed to UK law
A revocation of Article 50 would have to be initiated by the UK. It’s anticipated that parliamentary approval, via an act of parliament, would also be required to revoke Article 50, although some constitutional lawyers disagree. Even if parliamentary approval was not legally required, it’s difficult to imagine the government revoking Article 50 without parliament’s backing.
The June 2016 referendum imposed no legal obligation on the government to implement the result. However, the European Union (Withdrawal) Act 2018 sets the date of Brexit as March 29, 2019 in law. Crucially, it also repeals the European Communities Act 1972, which is the legislation that brought the UK into the EU. This means that a change in UK law is also required to stop Brexit.
So, to stop Brexit, Article 50 would need to be revoked, and, after that, the European Union (Withdrawal) Act 2018 must be repealed. Even if parliamentary approval is not required for the former, it is for the latter.
A new mandate from the public
In the UK’s democracy, parliament is sovereign and it would be entitled to try and stop Brexit if it wanted. Still, it’s implausible to imagine this parliament, or any future parliament, trying to stop Brexit without some form of electoral mandate.
A general election or second referendum could provide one. The Fixed-term Parliaments Act 2011 means that a general election is unlikely, as it would require two-thirds of MPs to vote in favour of one. Alternatively, a majority of MPs would need to vote in favour of a no-confidence motion against the government. If no new government can then be formed within 14 days, a general election would be triggered.
A second referendum is perhaps more likely. It would require primary legislation, and therefore the support of a majority of MPs. A referendum could come about via an amendment to the “meaningful vote” on the withdrawal agreement on December 11 which makes approval of it, or approval of the subsequent implementing legislation, conditional on a referendum.
A referendum could also emerge if MPs reject Theresa May’s deal. To avoid the UK leaving the EU without a deal – and if no better deal can be negotiated and win the support of parliament – MPs might then seek to force a second referendum to break the impasse.
Dominic Grieve’s amendment, passed on December 4 in a significant defeat for the government, makes such a move easier. By law, the government is required to produce a written statement to MPs outlining its plan, within 21 days of the deal being rejected.
MPs then vote on a motion on the basis of that statement. Grieve’s amendment now enables MPs to table amendments to this motion, thereby giving them much more political control over what happens next if the deal is voted down. If, at this stage, a majority of MPs support a second referendum, they could amend the motion to require one, and it could be politically impossible for the government to ignore their will.
A second referendum would require a minimum of 22 weeks to organise and hold. This means that Article 50 would need to be extended because there wouldn’t be enough time before the end of March 2019. It’s reasonable to assume that the EU would unanimously agree to an extension if it was for the purpose of a second referendum. The date of Brexit in UK law would also need to be amended, but this should not be a problem, if a majority of MPs have voted for a second referendum.
High levels of uncertainty
The path to stopping Brexit is fraught with legal uncertainty and political controversy. Although it’s possible – and more likely now than a few days ago – it remains a highly uncertain prospect. May’s deal could pass, perhaps in a second vote if the first ends in defeat. No deal still remains the default outcome, and so cannot be ruled out. Crucially, the UK will automatically leave the EU on March 29, 2019, with or without a deal, unless Article 50 is extended or revoked.
Amid the uncertainty, what’s clear is that stopping Brexit requires a majority in parliament to change the law, force a second referendum or general election, and revoke Article 50. It also requires a cooperative and patient EU, to allow for an extension of Article 50. Finally, it requires a willing public, which is probably the biggest obstacle on the tumultuous path to stopping Brexit.