Morgan McSweeney, the most powerful aide in Downing Street, resigned on Sunday as Prime Minister Keir Starmer's chief of staff — falling on his sword over the decision to appoint Lord Peter Mandelson as Britain's ambassador to the United States despite known ties to convicted pedophile Jeffrey Epstein.
Breitbart reported that McSweeney's departure marks the highest-profile casualty yet in a scandal that has consumed the Labour government since the U.S. Department of Justice released millions of Epstein-related files on January 30. In his resignation statement, McSweeney was blunt:
"The decision to appoint Peter Mandelson was wrong. He has damaged our party, our country and trust in politics itself."
He added:
"When asked, I advised the Prime Minister to make that appointment and I take full responsibility for that advice."
One aide gone. The man who actually made the appointment — Keir Starmer — remains in place.
This is not a story about a staffer gone rogue. Starmer himself admitted during Prime Minister's Questions that security vetting had flagged Mandelson's continued relationship with Epstein. He appointed him anyway.
Mandelson — widely known in political circles as the "Prince of Darkness" for his Machiavellian approach to power — took up the ambassadorial post in February 2025. He was sacked in September.
Documents released by the DOJ appeared to show that Mandelson had allegedly leaked confidential UK government information to Epstein when he was a British minister, including during the 2008 financial crisis.
On February 3, the Metropolitan Police announced a formal criminal investigation into Mandelson and searched two properties linked to him. He has since resigned from the Labour Party and stepped down from the House of Lords.
McSweeney, to his credit, acknowledged the people at the center of this:
"We must remember the women and girls whose lives were ruined by Jeffrey Epstein and whose voices went unheard for far too long."
He also conceded that, while he did not oversee the vetting process directly, "that process must now be fundamentally overhauled." Which raises the obvious question: if the vetting process flagged the Epstein connection and the Prime Minister appointed Mandelson regardless, what exactly is there to overhaul? The process worked. The people in charge ignored it.
Conservative Party leader Kemi Badenoch wasted no time identifying the real issue:
"It's about time. But once again with this PM it's somebody else's fault: 'Mandelson lied to me' or 'Morgan advised me'. Keir Starmer has to take responsibility for his own terrible decisions."
She's right. McSweeney's resignation provides Starmer a human shield, not an answer. The Prime Minister received the intelligence. The Prime Minister made the call. The Prime Minister's chief of staff is now the one packing his desk.
Reform UK leader Nigel Farage was characteristically direct, writing on X:
"As predicted McSweeney has gone. Labour are just continuing the chaos we saw under the Tories. My money says Starmer won't be far behind after Labour's disaster in the elections this coming May."
But the real trouble for Starmer isn't coming from the opposition benches — it's coming from his own side. Labour MP Brian Leishman said the Prime Minister must look at his own position and question whether he should follow McSweeney's lead one last time and resign "for the good of the country and the Labour Party."
Green Party leader Zack Polanski called for Starmer's resignation, saying the appointment demonstrated a "catastrophic level of misjudgment" and that Starmer "knew that Peter Mandelson was still friends with a notorious paedophile."
Meanwhile, former deputy Angela Rayner and David Lammy — reportedly Starmer's current deputy — have both been briefing the press against their boss, with allies of Lammy indicating he opposed the Mandelson appointment. The rats aren't leaving the ship. They're rewriting the passenger manifest.
McSweeney was no ordinary chief of staff. He served as the architect of Labour's internal purge against the hard left, helping to rout the left-wing acolytes of former leader Jeremy Corbyn and repositioning the party toward the political center.
He became director of the think tank Labour Together in 2017, a group whose stated aim was to oppose Corbynism. Corbyn was eventually kicked out of the party altogether.
McSweeney's orbit extended beyond domestic party politics. He was listed as a director at the Centre for Countering Digital Hate before resigning in April 2020, according to Companies House records.
The CCDH is now led by Imran Ahmed, a longtime McSweeney ally who was among five individuals sanctioned by the Trump administration in December 2025 with visa bans. The State Department cited "organized efforts to coerce American platforms to censor, demonetize, and suppress American viewpoints they oppose."
That a chief of staff with ties to an international censorship apparatus was also the man advising a Prime Minister to install an Epstein associate as ambassador to Washington tells you something about how this Labour government evaluated risk — not in terms of what was right, but in terms of what they thought they could get away with.
Starmer has appointed Jill Cuthbertson and Vidhya Alakeson as joint acting chiefs of staff. The new team inherits a government in freefall — a Prime Minister whose judgment is under fire from his own MPs, a police investigation into his former ambassador, and local elections in May that Farage is already circling.
Epstein was convicted in 2008 on state charges in Florida after pleading guilty to soliciting and procuring a minor for prostitution. He was sentenced to 18 months. Mandelson continued his close relationship with Epstein even after that conviction.
And Starmer — the former Director of Public Prosecutions, the man who built his career on the rule of law — looked at the vetting file, read the warnings, and handed Mandelson the Washington embassy anyway.
McSweeney said the appointment was wrong. On that much, everyone agrees. The question now is whether the man who actually made it will ever be held to the same standard as the aide who merely recommended it.
Don't hold your breath.
