Melanie Stansbury, a Democrat Representative for New Mexico who sits on the committee, revealed that anyone who contributed to the book may be summoned.
The declaration means that Lord Mandelson’s behaviour, activities and connections to Epstein could be part of the investigation.
This will bring further embarrassment for Starmer, who still faces questions about why it took so long for him to sack the ambassador.
Stansbury told Fox TV that the committee would investigate whether any of Epstein’s powerful friends may have been complicit in his wrongdoing, financial crimes and other secret business.
“Sometimes the cover-up is as important as the crime,” she said.
She said the committee had requested many unseen documents because “who knows what evidence was not prosecuted and how it implicates not only Epstein, but all of the people around him”.
In his message for Epstein’s 50th birthday in 2003, Mandelson described the financier as an “intelligent, sharp-witted man” who “parachuted” into his life.
The committee has already lined up Maxwell as a witness, and Stansbury said they were “currently working on a list of additional documents, witnesses and others associated with these crimes that the committee intends to move a vote for subpoenaing”.
“This is the entire oversight committee conducting this investigation,” she said.
Stansbury said: “We have asked for documents from the Treasury involving potentially illicit financial transfers that are involved in the sex trafficking scheme.
“And we’ve subpoenaed documents from the estate, which is where the birthday book came from.
“We are currently working on a list of additional documents, witnesses, and others associated with these crimes that the committee intends to move a vote for subpoenaing. Absolutely, we will be following up.”
Specifically referring to the birthday book, she added: “There’s a lot in this book, if you take time to look through the pages of what’s included in this book. It’s filled with all manner of disgusting allusions to Epstein’s predilection, not only for womanising, but for abusing young women.
“In fact, there’s notes even in the section of this book – because it was divided up by family and friends – even among the section among his family.
“People knew, people talked about it, people joked about it.”
The committee only has the power to subpoena US citizens, but they could still publicly issue a request for Mandelson to appear through a “formal letter of invitation”.
It is possible that the Duke of York, whose name has also been linked to Epstein, could face a similar request.
Stansbury said she wanted to uncover why Epstein was neither arrested nor properly investigated for his crimes in the 2000s by US attorney Alexander Acosta.
“We will be doing an interview in the oversight committee with Acosta, who was the attorney who was in charge of prosecuting this crime, the set of crimes that were involved,” she said.
“And there will be a lot of questions about the non-prosecution agreement that was signed. That is actually one of the documents that was produced by the estate.
“It is already public, but yeah let me just say this: sometimes the cover-up is as important as the crime, and what we know is that the crime in this case is not just sex trafficking and child rape and physical assault of women and children, but it also involves a massive network of financial institutions, hundreds of millions of dollars in funds that were money laundering.
“It involves organisations that were involved in trafficking, potentially young women from Eastern Europe. It involves potentially foreign governments.
“The survivors have told us there are FBI and CIA files that have not yet surfaced and financial documents. Because they have already been involved in criminal and civil lawsuits that have had those documents sealed.
“That’s why we need the White House to comply with the subpoena we’ve already issued to produce those documents to the committee because they are sitting on who knows what evidence was not prosecuted and how it implicates not only Epstein, but all of the people around him.”
The Democrat expressed her hope that Donald Trump could appear in front of the committee if members voted to make that move. However, Republicans are unwilling to do this.
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