Police are carrying out a criminal investigation into a row over the founding of Your Party, which split the leftwing party as it was established last year.
A spokesperson for London’s Metropolitan police said they had launched an investigation after they received a report in September 2025 “relating to the alleged unauthorised access of a political party’s database”, the Politico website reported.
Your Party was founded in summer 2025 by the former Labour leader Jeremy Corbyn and the former Labour MP Zarah Sultana, both of whom now sit as Your Party MPs in the House of Commons.
But relations between the different factions in the party have been strained since its creation in July last year. That September Sultana revealed a new membership portal on X, and encouraged members to become paying members for £55.
Corbyn described the site as a “false membership system” and told supporters to ignore an email requesting funds. Sultana said her only aim had been to “safeguard the grassroots involvement that is essential to building this party”, and later accused the party of being run by a “sexist boys’ club”.
Officers had now arrested a man on suspicion of an offence under the 1990 Computer Misuse Act, a police spokesperson told Politico. The man was released pending further inquiries and has not been charged.
Officers also previously interviewed a woman in her 30s under caution in connection with the same investigation. The spokesperson added: “The investigation continues.” The police spokesperson did not name any political party in their statement, and the spokesperson did not confirm which political party their investigation was related to.
Sources told the Guardian that the investigation was linked to the long-running dispute connected to the establishment of Your Party. Neither the man arrested nor the woman interviewed by police are MPs and neither have been charged with an offence. Neither Corbyn nor Sultana were accused of wrongdoing, Politico reported.
In January, it emerged that the Information Commissioner’s Office (ICO) advised the party that while it was taking no further action over the Your Party membership portal launch, it may have involved “serious criminal activity” and should be referred to the police.
A Your Party spokesperson said: “It would not be appropriate to comment any further about ongoing police investigations.”
They also said: “We can reassure our members and supporters that our systems are secure and that this was an isolated incident.”
Your Party has struggled to make a widespread national impact since it was founded, while the Green party of England and Wales, rebranded as an eco-socialist party, has seen its membership quadruple.
In February, Corbyn won a comprehensive victory to become the de facto leader of the leftwing startup party. He said Your Party would work with the Green party and others to push for a “coordinated left-flank offensive” against Reform and Labour. Sultana was also voted on to the party’s leadership committee under its collective leadership model.
Corbyn-backed candidates took 14 of the 24 available places on the party’s central executive committee (CEC). Sultana-backed candidates took seven of the seats and three went to independents.
