Pete Hegseth speaking at the Pentagon last week Credit NATHAN HOWARD/Getty Images Benedict Smith Washington Correspondent Show biography Benedict is based in Washington DC, where he has covered the Trump administration, the Russia-Ukraine war and the Epstein files. In 2025, he won the Press 30 Under 30 Award 11:00am BST Current and former Pentagon officials are set to “spill their guts” to Congress about Pete Hegseth, sources have said.

Democrats are preparing to investigate the US defence secretary if they regain control of the House after November’s midterms, and have already made contact with potential whistleblowers, The Telegraph can reveal.

They plan to subpoena Mr Hegseth’s inner circle and rake over controversies from his tenure, such as“Signalgate” when he accidentally leaked US military plans to a journalist.

With the help of informants, they hope to force embarrassing disclosures from his time at the Pentagon, which would either build an impeachment case against him or provoke Donald Trump into dismissing him.

Pete Hegseth meets with Britain’s Defence Secretary Wes Streeting at the Pentagon Manuel Balce Ceneta/AP Sources said the defence secretary is vulnerable because he has committed a string of costly blunders in office while isolating himself from potential allies.

“There’s going to be a lot of people that are going to very quietly go to the chair of the armed [services] committee and are going to spill their guts, provide them with everything they can and leak everything they can,” said a well-connected source. “It’ll be horrendous. It’ll be consistent embarrassment.”

“Hegseth has two huge problems,” said a former senior administration official.“Through his arrogance, he’s made many former allies willing to work with Democrats to hold his feet to the fire for all the damage he’s done to our military.”Mr Hegseth has forced out dozens of senior military officers, including Randy George, the former army chief of staff, and CQ Brown, the former chairman of the joint chiefs of staff.

Several members of the top brass have anonymously criticised the defence secretary, who last year summoned them to Quantico to criticise “fat generals” and lecture them on grooming standards.

Randy George, the former army chief of staff, was forced out by Mr Hegseth Win McNamee/Getty Images He has pushed out the department’s most senior civilian officials, purged aides and, according to a Pentagon source, provoked widespread disillusionment.

Some figures believe Mr Hegseth is a genuine “threat to national security”, while others simply “don’t like him”, another source said.

Three members of Congress, including a Republican, have already introduced articles of impeachment against him in the House. Republican senators have been dismayed by Pentagon turmoil and its lack of cooperation with them.

A Pentagon source said they would work with Congress to “provide insight” on how the department had been plunged into “chaos” under Mr Hegseth.

Hegseth and circle likely to face subpoenas Democrats will be armed with new legal powers if, as is widely expected, they regain control of the House in November’s midterms.

They are understood to be planning to issue subpoenas for Mr Hegseth and his closest advisers, including his wife, Jen Hegseth, and top aide, Ricky Buria.

“I hope he and his inner circle have some very strong legal insurance given what they’re facing once Democrats get the gavels,” said the former official.

Senior Pentagon officials who were forced out following infighting with Mr Hegseth, including Dan Driscoll the former army secretary, and John Phelan, the former navy secretary, are also likely to be called to give evidence.

A Democratic member of Congress, who asked to remain anonymous, said the eventual plan was to impeach Mr Hegseth, but not until “we have done a thorough investigation and have all the facts to hand”.

He said he had already been in touch with sources in the department but that potential investigations had been stymied by Republican control of Congress.

Mr Hegseth and his wife Jennifer Rauchet attending a prayer breakfast Alex Wong/Getty Images Democrats on the House oversight committee previously sought transcribed interviews with some of Mr Hegseth’s advisers who departed following a purge in April last year, but had no enforcement power to make them comply.

An investigation would likely involve the House oversight committee, the chamber’s main investigative body, the judiciary committee, which would draft articles of impeachment, and the armed services committee.

Impeachment remains a high bar even if Democrats are able to present a compelling case against Mr Hegseth, because it requires two-thirds of senators to vote to convict. No cabinet secretary has ever been convicted on impeachment charges.

Senate Democrats have suggested Mr Hegseth’s ousting is the price they will demand from Republicans for cooperation on defence issues, The Hill reported on Monday. Might Trump dump Hegseth?

Some believe a more likely prospect is that Mr Trump will drop his defence secretary to stem the flow of embarrassing stories from his administration they hope to unearth.

Although the president has been reluctant to hand the media scalps in his second term, he has dismissed several senior officials.

Mike Waltz was moved from national security adviser to UN ambassador for his role in the Signalgate scandal in May last year. Kristi Noem, the former homeland security secretary, was sacked after authorising a $220m (£164m) self-promotional advertising campaign, while Pam Bondi lost her job as attorney general following frustration at her handling of the Epstein Files.

On Friday, Mr Trump sacked Katie Zacharia the White House press secretary, after an unconvincing display at a briefing four days earlier.

Donald Trump may have Mr Hegseth next on his list of senior officials to go Jim Watson/AFP One focus of an investigation, Democrats say, will be the Signalgate scandal from March 2025, which saw Mr Hegseth accidentally leak military plans to the editor-in-chief of The Atlantic, Jeffrey Goldberg.

An internal Pentagon report from December criticised Mr Hegseth for violating security protocols and risking the safety of American pilots. It found he had discretion to decide what constitutes classified material as defence secretary, and therefore did not commit a criminal offence.

One source who has made contact with Democrats said Mr Hegseth would have had to declassify the material in writing and urged investigators to search for a paper trail.

“If he claims he somehow declassified a SECRET/NOFORN [not releasable to foreign nationals] communication from [US Central Command] minutes between receiving it and sending it to his wife and others, he will need to show the written memorandum ordering the declassification before texting the information,” they said. “Clearly that is risible on its face.”

Lingering threat of prosecution A former administration official noted that John Bolton, the former national security adviser and David Petraeus, Barack Obama’s CIA chief, were prosecuted for divulging classified information. “This is serious stuff,” they said.

Gen Petraeus was sentenced to two years of probation and ordered to pay a $100,000 (£75,000) fine. Bolton, who pleaded guilty and agreed to pay a $2.25m (£1.7m) fine, faces up to 60 months in prison.

However, while Congress can make criminal referrals, it cannot compel the department of justice (DoJ) to bring charges. Mr Hegseth has previously claimed the Pentagon investigation was a “total exoneration”.

Other probable focuses for a congressional investigation include the Iran War particularly the US’s shortage of missile interceptors, the strikes on alleged drug boats in the Caribbean and Eastern Pacific, and potential corruption.

The Democratic congressman suggested he would dig into Pentagon contracts to establish whether Mr Hegseth had benefited from any “sweetheart deals”. There is no suggestion this has taken place.