OPEN warfare in the Labour Party reached new heights yesterday as Jeremy Corbyn hit out at ruling officials over a successful bid to ban members from voting.

The party’s National Executive Committee (NEC) scored a major victory when the Court of Appeal ruled that it has the power to prevent 130,000 new members from taking part in the leadership vote.

A freeze date was set to block those with less than six months consecutive membership by July 12 from casting ballots, stating that this was to prevent “entryists” manipulating the outcome of the contest.

But a ruling expected to benefit Corbyn’s campaign was ruled unlawful by a High Court judge earlier this week after five affected members successfully argued that the party had promised them the right to vote on the leadership.

However, they were last night facing legal costs of up to £80,000 after a panel of judges said that verdict was wrong and the NEC has the power to set eligibility criteria as it sees fit.

Hitting out at officials, shadow chancellor John McDonnell said: “I just find it shaming for a democratic party like ours with a tradition of over a century of campaigning for democracy throughout our society.

“We are now undermining the democracy of our own party. They used a grubby little device.” Meanwhile, Corbyn’s campaign team said the decision was wrong “both legally and democratically”.

A statement issued on his behalf said: “The court’s ruling disenfranchises nearly 130,000 Labour members who joined the party since January and were explicitly told that they would have a vote in any leadership election.

“Crucial to the outcome today was the introduction of a new argument by the Labour Party HQ’s lawyers.

“They invoked an obscure clause in the Labour Party rules... which could be read as giving the NEC the right to ignore all of the rules laid out for leadership elections.

“In other words, this is a ‘make it up as you go along’ rule. We do not think that making it up as you go along is a reasonable way to conduct democracy in our party.

“Serious questions must be raised, however, over why and how the NEC procedures committee brought this appeal.”

Barrister Clive Sheldon QC, acting for Labour general secretary Iain McNicol, had told the court the NEC can override the rulebook, stating: “It is in effect the guardian of the party’s constitution and the ultimate arbiter as to the meaning of the rules.

“What we have done is consistent with the rules framework. But even if it were not, the NEC still has the power to go against the rules framework.”

In a written determination, judge Lord Justice Beatson agreed, stating: “A member’s entitlement to vote in a leadership election is not a product of him or her simply being a member, but is the result of him or her being a member who satisfies the precise eligibility criteria defined by the NEC and any freeze date provisions set by the NEC in the timetable for the election.”

NEC chairman Paddy Lillis insisted the party had been right to appeal, saying: “It is crucial to the Labour Party that our governing body has the authority to debate, decide and implement the procedures, timetable and voting eligibility for our internal elections and selections.

“The original court decision had wide-ranging implications for the party and the authority of our governing body.”

The verdict is expected to improve the chances of leadership contender Owen Smith. Reacting to the result, he said: “I don’t think it changes anything for me. I’m just going to carry on getting around the country talking to members – old and new members – and trying to persuade them that the crisis that I see in the country and the crisis that I see in the Labour Party, we’ve got to solve them both.

“That requires healing the party, uniting our party once more and getting us ready to take back power.”

However, the case may not yet be over – although appeal judges refused the five members permission to appeal to the Supreme Court, they can still ask the Supreme Court justices directly to consider their case.

Solicitor Kate Harrison said a decision would not be made until after the appeal court judgment had been fully analysed.

Meanwhile, David Goldstone QC, who represented the five, indicated in court that steps which could lead to a hearing next Tuesday had already been taken.

One of the group, the Rev Edward Leir, said: “It’s easy to forget that, in all the political turmoil, we’re just five ordinary members of the Labour Party who wanted to stand up for tens of thousands of others.”

The crowdfunder for the group topped £54,800 by 7pm last night after a rush of donations.