A crowd funder to pay for a legal challenge to the Conservative government’s deal with the DUP has been launched today with the backing of the Scottish Greens.

A former candidate for the Green Party in Northern Ireland has instructed the London law firm which challenged the Brexit vote to begin a High Court bid to overturn the DUP’s agreement to back the UK government on a range of votes.

Ciaran McClean must raise thousands of pounds to pay Edwin Coe LLP, which represented one of the successful lead claimants in the article 50 judicial review case at the Supreme Court.

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McClean’s lawyer David Greene sent a legal letter to the government claiming the DUP deal is in breach of the 1998 Good Friday agreement, under which the UK government undertook to exercise its power in Northern Ireland “with rigorous impartiality on behalf of all the people in the diversity of their identities and traditions”.

McClean said the government’s reply arrived on Friday and although he refused to disclose details of the response on the advice of his legal team, it prompted him to set up a crowd funder which he hopes will raise £20,000.

The 53-year-old mental health worker, who stood for the Greens in the Westminster seat of West Tyrone in 2015 and 2017, said: “It’s a lot of money when you don’t have any but as a citizen of the UK I must do what I can to protect the integrity of our democracy.

“The definitive wording in the Good Friday agreement is that the government have to act with rigorous impartiality and I don’t believe the Tories can do that when they are in league with the DUP.”

McClean from Sixmilecross, near Omagh, was in the town on August 15 1998 when the Real IRA detonated a car bomb, killing 29 people and injuring 220 others.

“I lost friends and neighbours,” he said. “When you’ve lived as I have through some of the most brutal things in the Troubles here in Northern Ireland, where we didn’t really have democracy because it was usurped all the time by violence, which was the norm, it’s part of our civic responsibility to protect the Good Friday agreement.

“We’re already seeing the destabilising effect of the DUP deal. We don’t have an assembly here now and Sinn Fein is using that as a reason not to re-enter a power sharing agreement.”

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A spokesman for the Scottish Greens encouraged Scots to donate to the crowd funder, when it goes live.

He said: “The deal between Theresa May's desperate Tories and the anti-equality DUP is pure pork-barrel politics, and undermines how the nations of these islands are funded. It also undermines the UK Government's role as an impartial broker in talks over Northern Ireland's future.

“Ciaran's legal challenge gives voice to the anger and frustration many people feel and we wish him the best of luck.”

MacLean welcomed the support from the Scottish Greens and urged anyone in Scotland who is opposed to the deal to donate.

He added: “This is a matter for anyone who’s concerned about openness and transparency and holding government to account. That crosses the political spectrum. I would welcome support from anywhere.”

You can visit the case page, Challenge to UK Government/DUP deal for breaking Good Friday Agreement​, by clicking HERE