Police have warned that the release of a key document relating to the vetting of Peter Mandelson could compromise the Metropolitan Police’s ongoing criminal investigation and jeopardise any future prosecution, prompting the Cabinet Office to confirm it will not be made public.
Police warning over prosecution risk
Scotland Yard launched an investigation into allegations of misconduct in public office in February 2026 after claims that Lord Mandelson shared sensitive government information with the disgraced financier Jeffrey Epstein while serving as Business Secretary in 2009. The former Labour minister was arrested on 23 February and released on bail. He has denied any wrongdoing.
A Metropolitan Police spokesperson said: “An investigation into alleged misconduct in public office is underway and it is vital due process is followed so that our criminal investigation and any potential prosecution is not compromised. We are working with the Cabinet Office to review relevant documents provided to us by them. While complying with the Humble Address is a matter for government and parliament, we have asked the Cabinet Office not to make some documents public as they would have a detrimental impact on our investigation or any subsequent prosecution.”
Any failure by Lord Mandelson to declare a possible conflict of interest during the vetting process could itself constitute misconduct in public office, the police have indicated.
Withheld document and vetting concerns
The document in question is a nine-page summary compiled by the UK Security Vetting Agency (UKSV) before Lord Mandelson’s appointment as ambassador to the United States. The Cabinet Office had previously insisted the summary had been shared with Parliament’s Intelligence and Security Committee (ISC) and that redactions had been mutually agreed. Now, however, it will not form part of a second tranche of documents expected to be published in June.
UKSV’s assessment flagged a series of concerns that led to a recommendation that Lord Mandelson be denied developed vetting clearance. The agency noted his links to senior figures in China (Finance Minister Lan Fo’an), Russia (sanctioned oligarch Oleg Deripaska) and Israel (former military intelligence general Tamir Hayman). A £1 million loan he received for an investment in an Israeli start-up was also highlighted, along with a potentially compromising relationship with an unnamed British individual. UKSV concluded that Lord Mandelson appeared naive about the risk of his historical associations being exploited.
Despite the agency’s assessment that he posed a “high” overall concern, the then Foreign Office permanent secretary, Olly Robbins, granted security clearance on 29 January 2025. Prime Minister Sir Keir Starmer has stated he was unaware of the failed vetting until April 2026 and insisted he would not have appointed Lord Mandelson had he known.
ISC criticism and document release
MPs had demanded the release of documents relating to Lord Mandelson’s appointment using a parliamentary motion known as a humble address, which allows Parliament to petition the monarch for government papers. It was agreed that sensitive material, including information that could compromise international relations or national security, would be passed to the ISC for review.
However, the ISC has since accused the government of applying redactions “far too broadly”. The committee’s chairman, Lord Beamish, said ministers should seek Parliament’s permission to exclude information on non‑security grounds. A significant omission from the documents released so far is any written record of measures taken to mitigate the serious security concerns identified by UKSV, casting doubt on assurances given to MPs that such mitigations were in place.
A government spokesperson said: “We are committed to complying with the Humble Address in full. The second tranche of documents will be among the largest publications ever laid in Parliament. That reflects the transparent and thorough process we have followed, in line with established precedent for Humble Addresses.”
Ongoing criminal and other investigations
The Metropolitan Police investigation centres on allegations that Lord Mandelson passed sensitive, confidential government information to Jeffrey Epstein while serving as Business Secretary. Leaked emails reportedly show him forwarding internal government communications, including details about an EU bailout package during the 2008 financial crisis. There are also suggestions that Epstein provided financial benefits to Lord Mandelson and his partner, including funding for an osteopathy course.
Lord Mandelson was sacked as ambassador in September 2025 after his continued friendship with Epstein – who was convicted of child sexual offences – came to light. The case has prompted calls for a review of the misconduct in public office offence as part of the Hillsborough Bill to ensure greater political integrity.
Separately, the European Union has ordered its anti‑fraud office, OLAF, to investigate Peter Mandelson over his ties to Jeffrey Epstein while serving as the EU’s trade representative. The Epstein files have also led to investigations involving other high‑profile figures, including Prince Andrew, who was arrested on suspicion of misconduct in public office.
