Capitol Hill Republicans are wielding all tools available to them to uncover any potential misconduct by former President Joe Biden’s top White House aides.

House Oversight and Government Reform Committee Chairman James Comer announced Thursday that he was issuing a formal subpoena to Biden’s former White House Physician, Dr. Kevin O’Connor.

The move is the latest escalation as the top Republican-led committee is ramping up its investigation into the ‘cover-up’ of former President Joe Biden’s mental decline.

Chairman Comer ordered O’Connor to appear for a deposition on June 27 before his committee. 

Comer’s subpoena comes on the heels of President Donald Trump’s Wednesday announcement via ordering a federal investigation into former President Biden’s staff.

‘This conspiracy marks one of the most dangerous and concerning scandals in American history.’

‘The American public was purposefully shielded from discovering who wielded the executive power, all while Biden’s signature was deployed across thousands of documents to effect radical policy shifts,’ Trump said in the order.

Former President Joe Biden appears for his sound check before the start of the 2024 Democratic National Convention at the United Center in Chicago, Illinois on Monday, August 19, 2024

Five additional former top Biden White House aides were summoned by Comer to appear for transcribed interviews on Wednesday, after five other top staffers – including Dr. O’Connor – were called by the committee in May. 

If they did not voluntarily comply with the committee request, Comer threatened to issue subpoenas this week to compel their appearances.

Comer’s investigation is doing a deep-dive into the alleged cover-up of Biden’s mental decline as well as allegations of potential unauthorized usage of an autopen during the former president’s White House tenure.

He called the cover up by Biden’s former staffers ‘one of the greatest scandals in our nation’s history’ in a statement to the Daily Mail.

‘The American people deserve full transparency and the House Oversight Committee is conducting a thorough investigation to provide answers and accountability. The cover-up of President Biden’s mental decline is one of the greatest scandals in our nation’s history,’ Comer noted on Wednesday. 

‘These five former senior advisors were eyewitnesses to President Biden’s condition and operations within the Biden White House. They must appear before the House Oversight Committee and provide truthful answers about President Biden’s cognitive state and who was calling the shots, ‘ said Chairman Comer.

The latest round of Biden staffers summoned by Comer to appear for transcribed interviews are as follows:

Former Biden White House Chief of Staff Ron Klain

• Michael Donilon, former Senior Advisor to the President

• Anita Dunn, former Senior Advisor to the President for Communications

• Ronald Klain, former Chief of Staff

• Bruce Reed, former Deputy Chief of Staff for Policy

• Steve Ricchetti, former Counselor to the President

Biden’s Former Senior Advisor to the President for Communications Anita Dunn

Biden’s longtime White House physician is also at the center of scrutiny, and was included in Comer’s first round of testimony requests.

MAGA loyalists led by Fox News host Jesse Watters set their sights on Dr. Kevin O’Connor, demanding he be subpoenaed and forced to answer questions on the record about Biden’s health.

‘He needs to be brought in, he needs to be subpoenaed, and he needs to answer some of these questions,’ Watters said last month.

He’s at the top of the list according to Comer, who said he’s calling on physician and former White House advisors to ‘participate in transcribed interviews so we can begin to uncover the truth.’

Rep. James Comer (R-Ky.) speaks to a reporter as he arrives for a House Republican conference meeting at the U.S. Capitol on May 6, 2025 in Washington, DC

‘In the last Congress, the Biden White House blocked these individuals from providing testimony to the Oversight Committee as part of the effort to cover-up Biden’s declining health,’ Comer noted in May.

The top former Biden White House staff called to testify by the committee in the first round of interview requests included the following: 

Kevin C. O’Connor, former President Joe Biden’s White House doctor

• Dr. Kevin O’Connor, President Biden’s Physician

• Neera Tanden, Former Director of the Domestic Policy Council

• Anthony Bernal, Former Assistant to the President and Senior Advisor to the First Lady

• Annie Tomasini, Former Assistant to the President and Deputy Chief of Staff

• Ashley Williams, Former Special Assistant to the President and Deputy Director of Oval Office Operations

Neera Tanden on Capitol Hill in Washington, U.S., February 10, 2021

Three of the individuals – Tomasini, Bernal, and Williams – had been subpoenaed by the Oversight Committee during the previous Congress. 

At the time, the Biden administration blocked the subpoena and did not make the president’s aides available for depositions or interviews. 

Biden’s former Attorney General Merrick Garland also blocked a request from Chairman Comer for audio records from the investigation into President Biden’s mishandling of classified documents by Special Counsel Robert Hur.

‘Any continued obstruction will be met with swift and decisive action. The American people demand transparency and accountability now,’ said Chairman Comer in May.

The vast nature of the ‘cover-up’ of former President Biden’s mental state is the subject of a new book Original Sin in which an individual alleged to have had an inside view of the internal dynamic at the Biden White House is quoted as saying ‘five people were running the country, and Joe Biden was at best a senior member of the board.’