Fresh legal challenges aimed at preventing a hard Brexit will be launched this month as MPs craft parliamentary amendments in the hope of securing a second vote on any final deal with the European Union.

Ireland’s courts will host an ambitious crowdfunded attempt to refer an appeal to the EU’s highest tribunal about whether the process of Brexit is reversible. A letter before action is being sent to the Irish government on Friday, and it is intended that the application will go before judges in Dublin in the spring.

Meanwhile, the high court in London will hear a claim brought by two sets of claimants arguing that the UK should remain in the European Economic Area after Brexit. The challenge is likely to be heard during the week after next.

No date has yet been confirmed for the supreme court’s verdict on the article 50 challenge, which the government is widely expected to lose. The 11 justices will rule on whether ministers can use their powers under the royal prerogative to inform Brussels officially that the UK intends to leave the EU, or whether parliamentary sovereignty means that an act is required.



Ministers are understood to be preparing legislation so that parliament can approve triggering Brexit. It is expected to pass despite Europhile opposition in both houses.



The main claimant before the Dublin courts will be Jolyon Maugham QC, a London tax specialist who is coordinating efforts to argue that article 50 of the Lisbon treaty, which formally begins a country’s exit from the EU, can be reversed if a country changes its mind and decides not to leave.

Maugham, who has rights of audience in Dublin, said: “The UK must retain sovereignty over the shape of its future relationship with the EU. If we change our minds, we must be able to withdraw the notice without needing the consent of the other 27 member states. I want to establish clarity for British voters and deliver sovereignty to the British parliament over the question of its future relationship with its biggest trading partner.”



He said elected politicians may join him in the case as plaintiffs. In the space of a few days his crowdfunding campaign raised £70,000, largely in donations of £50 or less.

British judges and claimants have so far been reluctant to refer questions about Brexit to EU judges in Luxembourg. Maugham’s challenge, nominally against the Irish government, will try to persuade Irish judges to refer the question of article 50’s revocability to the European Court of Justice (ECJ).

If the ECJ were to rule that article 50 is revocable, it would enable the UK to reject the outcome of Brexit negotiations should they not prove acceptable to parliament or voters, and remain in the EU.

The high court case in London about staying in the European Economic Area was initiated by Peter Wilding and Adrian Yalland. Wilding runs the pro-single market organisation British Influence. A group of four anonymous claimants – a mix of overseas, EU, EEA and UK nationals – have joined the judicial review challenge, claiming that separate parliamentary approval is needed to quit the EEA.

Article 127 of the EEA agreement requires contracting parties, which include the UK, to give at least 12 months’ notice before leaving, the claimants point out. They say that implies a separate departure process from the one set out in article 50 of the EU treaty that has been disputed in the supreme court.

Opponents of hard Brexit hope to use defeat for the government in the supreme court as an opportunity to build momentum, even if most accept that the invocation of article 50 is inevitable.

In the House of Commons, the Labour party is confident of tabling a procedural amendment that might attach conditions, such as an agreement for parliament to review whatever exit deal is achieved towards the end of the two-year process. The Liberal Democrats and Scottish Nationalist party are expected to attempt more radical amendments.

A Labour source said its aim was to find something that would garner Tory support and pass rather than making what it viewed as more symbolic gestures.

Similar discussions are under way in the House of Lords, where cross-benchers and pro-European Tories have held meetings in recent weeks to discuss whether they would seek amendments of their own. These are complicated, however, by a concern among many peers that any unilateral action in the upper chamber would be branded anti-democratic.

Instead, the hope is that pressure for another vote among MPs before March 2019 will be irresistible, particularly if the court has already ruled that they have a right to be consulted at the outset of the process.

“Given that the European parliament has demanded that it have a chance to review the deal in good time, it would be very hard for the British government to argue that MPs should have less say – especially since this is all meant to be about returning sovereignty to Westminster,” said Hugo Young, a campaigner for greater transparency in the Brexit process.