Labour’s ruling national executive committee (NEC) has appointed a four-person panel to investigate the leaked internal report describing a “hyper-factional” environment among party staff hostile to Jeremy Corbyn. The unredacted report, which was leaked last month, reignited the row in the party over Labour’s handling of antisemitism cases, and led to calls for party members named in it to be suspended. A party spokesperson said on Friday that Martin Forde QC would chair the investigation, which will cover both the contents of the report, and the circumstances of its release. A spokesperson said Forde would be supported by three experts in “the law and the Labour party’s structures”, and would examine “the circumstances, contents and release of an internal report”. “The NEC has agreed that the investigation should endeavour to deliver its report by the middle of July,” the spokesperson said. The report included hundreds of private WhatsApp messages from named staff members, many of them expressing hostility towards Corbyn or his close allies and bemoaning Labour’s better-than-expected performance at the 2017 general election. The officials discussed funnelling election campaign funds to favoured candidates, including the former deputy leader Tom Watson. The dossier also named complainants in antisemitism cases. It was prepared as a background document, intended to be submitted alongside Labour’s response to the Equality and Human Rights Commission’s investigation into the party. When Labour’s lawyers decided the document should not be submitted, it was leaked. Starmer said at the time he was “shocked” by its contents, and by the fact that it had been published. His handling of the sensitive issue is regarded by both sides of the party as an early test of his leadership. In addition to Forde, the panellists will be three Labour peers: Debbie Wilcox, a former leader of Newport city council; Larry Whitty, a former Labour party general secretary, and Ruth Lister, an emeritus professor of social policy at Loughborough University. Some leftwing NEC members objected to the makeup of the panel. They argued for the veteran campaigner Lord Dubs, who is Jewish, to be included – but were defeated 18-16 in a vote. A Labour source said:, “Keir and Angela [Rayner] hold Alf Dubs in the highest regard, as we all do, but it is crucial that the panel is not just independent but perceived as independent. Keir did not think it would be appropriate for someone who was a high profile supporter in his leadership campaign to be involved.” A spokesperson for Momentum said: “It is critical that the inquiry focus on the very serious allegations of racism, sexism, senior staff members trying to sabotage Labour’s 2017 general election campaign and a failure to pursue antisemitism cases. “In any other organisation, members accused of racism, sexism and misuse of funds would be suspended pending investigation. Labour should be no different, and we call on Labour to suspend those named in the report while the investigation is ongoing.”