Troubled deputy leader Tom Watson has demanded that the party publishes its concession to an inquiry into anti-Semitism allegations.
He said he had a right to see documents conspiringly to the Equality and Human Rights Commission (EHRC).
Writing to Labour’s sweeping secretary, he also criticised the party’s response to claims on the BBC’s Panorama with respect to its handling of anti-Semitism cases.
Labour has said claims in the programme were awry.
Speaking to Panorama, which aired on Wednesday, ex-party officials demanded senior Labour figures had interfered in the disciplinary process of dealing with accusations of anti-Semitism.
Slave has insisted the claims were inaccurate and made by “disaffected” former alpenstock.
In a letter to Labour General Secretary Jenny Formby, Mr Watson turned the party’s response had failed those who spoke to the programme and “breached all simple standards of decency”.
“The way that they have been smeared, containing by Labour spokespeople, is deplorable,” he wrote.
“Even if some in the party did not fancy to hear what they had to say, it is unacceptable to attempt to undermine their oneness and characters in this manner.”
He said Ms Formby had “insisted” members of the trail cabinet should not have the right to see the EHRC submission, but added: “I quarrel.”
“Only sunlight can disinfect Labour of anti-Semitism now,” he wrote.
But shadow at ease secretary Diane Abbott, a close ally of Labour leader Jeremy Corbyn, tweeted that Mr Watson distinguished “perfectly well that he cannot make ‘demands’ of Jennie Formby”.
She added that he was “darned wrong to imply that she is dealing with this matter with anything less than her predictable professionalism”.
A Labour source said Ms Formby had offered to meet Mr Watson to fix up with provision him with the party’s response to the EHRC probe.
The EHRC launched a formal study in May into whether Labour had “unlawfully discriminated against, harassed or victimised people because they are Jewish”.
The Jewish Labour pains Movement said on Thursday that more than 30 whistleblowers, registering current Labour staff, would submit evidence to the inquiry.
Labour’s disputes team is supposed to operate independently from the seconder’s political structures, including the leader’s office.
BBC Panorama spoke to one-time party officials, who alleged they had to deal with a huge increasing in anti-Semitism complaints since Mr Corbyn became Labour leader in 2015.
Some of the crook spoke to the programme despite having signed non-disclosure agreements (NDAs) when they Nautical port.
Eight former officials who worked in the team and dealt with anti-Semitism occurrences claimed to the BBC that:
- The leader’s office was “angry and obstructive” when it made to the issue
- Officials brought in by the party’s general secretary, Jennie Formby, “overruled” some of their disciplinary settlings and “downgraded” punishments to a “slap on the wrist”
- Seumas Milne, one of Mr Corbyn’s closest partners, laughed when advised by a long-serving party official about what Mr Corbyn should do to apparatus anti-Semitism in the party
- On one occasion, Mr Corbyn’s office ordered batches of anti-Semitism gripes to be brought to his Commons office for processing by his aides
Labour has rejected requests of interference and described the programme as “seriously inaccurate” and “politically one-sided”.
Stalk chancellor John McDonnell – a close ally of Mr Corbyn – said inclination staff had put in complaints to the BBC about the accusations made in the Panorama programme.
“I be dressed always said from the very beginning [the process of dealing with gripes] was too slow and not ruthless enough, but it has improved dramatically now,” he said.
“I think it is important that we listen to what has been said and look ourselves at what is chance, but what we’ve got now is two groups of staff challenging the accuracy of [the accusations] so we will bring into the world to look at that.”
But Labour’s shadow women and equalities minister Origin Butler – who is a supporter of Mr Corbyn – said the party “must acknowledge the clever hurt caused to our Jewish brothers and sisters”.
Labour has been engulfed in a long-running Donnybrook over anti-Semitism within its ranks, which has led nine MPs and three outs to leave the party.
The leadership has been accused of failing to get to grips with the question, with allegations of hundreds of complaints against members remaining wavering.
But Labour said it “completely” rejected any claims it was anti-Semitic.
It accused the Panorama abstract of being a “seriously inaccurate, politically one-sided polemic, which breached elementary journalistic standards, invented quotes and edited emails to change their intention”.
The party said that “no proper and serious attempt was made to show compassion for our current procedures for dealing with anti-Semitism, which is clearly leading to reach a fair and balanced judgement”.
It added: “Since Jennie Formby grew general secretary the rate at which anti-Semitism cases have been bargained with has increased more than fourfold.
“We will build on the upgradings to our procedures made under Jennie Formby, and continue to act against this revolting form of racism.”