Labour is facing a legal bill of £5.5 million — and possibly far higher — as a result of the toxic legacy of antisemitism under previous leader Jeremy Corbyn, the JC can reveal.

On Wednesday the party formally apologised to seven BBC Panorama whistle-blowers and the journalist John Ware for ”untrue and defamatory” comments made against them after the programme was aired last July.

While the total bill for settling this claim is understood to have cost the party around £500,000, its lawyers have warned the party that it faces a bill in excess of £4 million alone over cases brought against it in relation to the apparently deliberate leaking of a Corbynite report into the handling of antisemitism.

In addition, potential data protection offences committed by the party over the leaking of those named in the report may result in a hefty fine from the Information Commissioner’s Office.

More than 50 individuals — many of whom were Jewish Labour members who had made complaints about instances of antisemitism in the party — are now also pursuing costly legal claims against the party after their names were circulated over social media, including a far-right website in America.

Meanwhile, the publication of the forthcoming Equalities and Human Rights Commission’s investigation into Labour’s handling of antisemitism under Mr Corbyn could leave the party open to a raft of discrimination claims from Jewish members if the watchdog’s report confirms that they have suffered from discrimination under the hard-left leadership .

Mark Lewis, the lawyer who handled the Panorama libel case against the party, confirmed that Wednesday’s settlement was “the first battle of many battles.” He added that the leaked Labour report had seriously harmed a “whole list of people” and would now “have to be challenged in the courts.”

Another Labour source told the JC the party had been given a “worst case scenario” of legal costs relating to the failure to stamp out anti-Jewish racism that was in excess of £8 million in total.

Labour leader Sir Keir Starmer has instructed Shadow Attorney General Lord Falconer to manage the party’s response to the legacy of Mr Corbyn’s failure on antisemitism.

Sir Keir is convinced Labour will remain unelectable unless he shows that he has fully rid the party of the “stain” of antisemitism and that it is “under new management” in the post-Corbyn era.

In the first of the party’s legal settlements over antisemitism on Wednesday, the party said it was “profoundly sorry” for ”untrue and defamatory” comments made against seven antisemitism whistle-blowers and the BBC journalist John Ware following the broadcast of an episode of Panorama last July.

Lawyers for Labour said the party now accepted that allegations made in a press release that Mr Ware had “invented quotes, flouted journalistic ethics” and had “knowingly promoted falsehoods, including by misrepresentations of fact and, by fabricating facts” were defamatory of the experienced journalist.

“All these allegations are false and the Labour Party unreservedly withdraws these allegations and is profoundly sorry for the distress caused by their publication and republication,” said the statement

In the Statement in Open Court the party agreed to pay “substantial damages” — thought to be around £200,000 in total — to the seven whistle-blowers — Katherine Buckingham, Michael Creighton , Sam Matthews, Daniel Hogan,  Louise Withers Green, Benjamin Westerman and Martha Robinson, who were all former employees of the party. They also paid substantial damages to Mr Ware.

Outside the High Court, five of the Panorama whistleblowers told how the group decided they “could not stay silent when we saw antisemitism permeate all levels of the Labour Party.”

On behalf of all seven, Martha Robinson said it would “take time to repair the damage” to their reputations as a result of the attacks mounted on them by the party.

Ms Robinson added: “As staff, we tried our best to tackle this issue but, in the end, we had no choice but to blow the whistle in public and make sworn statements to the EHRC.”

But senior figures from the party’s former leadership have reacted angrily to the settlement. On Tuesday night, the JC revealed that Unite had instructed lawyers from Carter Ruck on behalf of Jeremy Corbyn, Jennie Formby and Seumas Milne to force Labour to give them advance sight of the party’s apology. 

After the apology, Mr Corbyn issued a statement attacking the settlement, saying it was a “political” rather than “legal” decision. He then claimed that “evidence in the leaked Labour report” — which is the subject of an independent investigation by the QC Martin Forde — “strengthened concerns about the role played by some of those who took part in the (Panorama) programme” with regards to “inaccurate allegations about action taken to tackle antisemitism” in Labour.

The former leader was joined by ougoing Unite General Secretary Len McCluskey who also sang the praises of the leaked report.

Mr Ware and some of the whistleblowers have now instructed Mark Lewis to pursue a defamation case against Mr Corbyn and Mr McCluskey over their statements.

The JC also understands that legal advice given to Labour suggests that the contents of the leaked report are “a nightmare” in terms of potential legal costs for the party.

Another senior Labour source said: “Parts of the report appear to have been compiled by people with no understanding of the laws of defamation.” Numerous claims covering the Data Protection Act, invasion of privacy and libel have already been submitted to the party relating to the leaking of the report.

Ex-Shadow Chancellor John McDonnell has confirmed the report was commissioned by former General Secretary Jennie Formby with a view to submitting it as evidence to the EHRC. But Labour’s own lawyers blocked the move after saying submitting it would not be helpful to the party.

Lawyer Mark Lewis claimed the leaked report was “a bit like the soldiers leaving a barracks that they have to desert and setting it on fire. For four years, people in Labour have said there is no antisemitism in the party, it’s just a smear. Now they say that of course there was antisemitism, ‘but it just wasn’t us.’” 

The JC has learned that Lord McNicol, the former Labour general secretary, is considering legal action against leading left-wingers over claims he has been defamed in the report and by subsequent comments about him.

In September, Labour also faces another potential legal nightmare with the publication of the EHRC report into antisemitism. 

The closely guarded report (which has been submitted in draft format to Sir Keir, new General Secretary David Evans and only a few others) is likely to confirm systematic discrimination against Jewish members.

It is understood that any of those named in the EHRC report would be entitled to bring discrimination cases against the party around allegations of personal injury.

The upper limit for personal injury claims is believed to £47,000.  Although another senior lawyer said discrimination claims could in principal reach thousands of pounds.

 The JC can reveal that the Jewish Labour Movement is considering bringing a class action against Labour on behalf of its members if the EHRC report confirms they have been discriminated against.

But not all JLM members would be willing to fight the party for money. Many are supportive of the actions being taken to rid the party of antisemitism under Sir Keir.

Some would tell the JLM leadership to settle for a donation to a chosen charity as a settlement for claims over the EHRC findings.

Others, however — including former MPs and party members who quit the party as a result of antisemitism —- are likely to be less forgiving.