Every day or so there is a development that seems to raise the hopes of many remainers that Brexit will not happen in March next year.

One source of encouraging news is the Cambridge Analytica story, where serious allegations indicate issues relating to the referendum campaign that are genuinely concerning and need to be fully investigated.

Another is the regular disclosure of government chaos and lack of preparation, and the assumption that this will somehow mean Brexit will not go ahead. And there are hopes that a “final say” parliamentary vote will mean a last gasp exit from Brexit.

Brexit will collapse, some think, because of its own contradictions and complications.

All this is wishful thinking. None of these developments will stop Britain’s exit from the EU happening in a year’s time. The country will leave the EU by automatic operation of law on 29 March 2019 unless one of three things happen. And unless there is a “pathway” to one of these three things, the adverse developments are just noise and distraction.

The first way Brexit will not happen on time is if the EU and UK agree to extend the two-year Article 50 period to carry on negotiating the terms of the UK’s withdrawal. This is a possibility, but the settled view of the EU is that it should only happen in an emergency,and any extension should be short.

The second way is if the EU and UK say in the withdrawal agreement itself that the departure date will be after 29 March 2019. This would be a rather sensible move, and if 31 December 2020 were fixed on, there would be no need for elaborate “transition” arrangements. But Brexit, at least from the UK’s side, is not about doing sensible things.

These approaches simply change the date of Brexit, rather than stop it. But the committed leavers in the government will not accept either of them. Many of those in favour of Brexit just want to get the UK “over the line” next year and out of the EU, and all else is detail.

The third possibility is if it is cancelled altogether. There is no serious doubt that this is possible in theory, even though Article 50 is silent on revocation. If the UK sincerely sought to end the process, rather than cynically to re-set the clock to improve its negotiation position, then the EU would be minded to accept the revocation.

But there seems no serious possibility of such a dramatic reversal. The “mandate” of the referendum will remain, and those who still dispute that there is a mandate are akin to the generals who keep fighting the battles of a previous war.

Parliament approved the right of the prime minister to make the Article 50 notification at a time of her choosing. Both the government and the opposition front benches support Brexit. And there is probably now not enough time for the primary legislation needed for a fresh referendum.

Significantly, there is no pressure from the EU for Britain to cancel the process. The EU has skilfully protected its own position with the withdrawal agreement and December’s joint progress report. Even the Irish border issue has an accepted “backstop” where the UK has unilaterally committed to keeping Northern Ireland in the customs union and single market, unless there is agreement otherwise. The EU does not want Brexit, but is braced for it.

As Wolfgang Manchau has shown from a non-legalistic perspective, the time for revocation has passed. This post complements that analysis by showing that each of the three possible legal ways in which the date could be delayed, or Brexit cancelled altogether, seem blocked. There is no path to walk or glide down.

The periodic excitement that Brexit could be stopped by the uncovering of irregularities in the referendum is akin to when some on the political left believed “Tory election fraud” would mean the 2015 general election being nullified and the Conservatives losing their overall majority. As it happened, it took Theresa May’s folly to remove the party’s majority in the 2017 election, not proof of electoral malpractice.

But little is inevitable in policy and law: if the political will changes, the legal dots will be joined. A combination of bad news and political upheaval could still mean that the politics of Brexit could change and the process delayed or cancelled. But it seems ever more unlikely.

A better course for those who want the UK to remain close to the EU, and to rejoin as quickly as possible, is to accept there is a mandate to leave, but to aver that that mandate will be discharged on, and so have no further effect after, 29 March 2019.

The slate will be clean. There will be a path to rejoining under Article 49, and there will be a path to an association agreement that keeps the UK in the single market and the customs union, even if not as a full EU member. Those paths are open and, once the mandate is discharged, clear from any obstacle.

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