Comer requested last month that O’Connor voluntarily participate in a transcribed interview, but the physician declined. During the previous Congress, Comer made a similar request for O’Connor to speak about his medical evaluations and potential ties to the Biden family’s alleged influence-peddling operation. However, the White House prevented him from testifying.

O’Connor is the most recent former Biden associate to come under scrutiny by the Oversight Committee. This week, Comer also called for transcribed interviews with several of the president’s senior advisers including former White House chief of staff Ron Klain, former senior adviser to the president Michael Donilon, former senior adviser to the president for communications Anita Dunn, former deputy chief of staff for policy Bruce Reed, and former counselor to the president Steve Ricchetti.

Amid the book release of Original Sin and emerging reports of memory lapses during Biden’s tenure, alongside claims that his aides attempted to hide these health problems, Republicans have ramped up their investigation into the administration.

“Given your connections with the Biden family, the Committee sought to understand if you contributed to an effort to hide former President Biden’s fitness to serve from the American people,” Comer wrote in the subpoena. “You refused the Committee’s request. However, to advance the Committee’s oversight and legislative responsibilities and interests, your testimony is critical.”

Biden’s aggressive prostate cancer diagnosis has intensified Republican scrutiny of his overall health and cognitive abilities while in office. President Donald Trump has also launched an unprecedented investigation into the Biden administration, citing concerns that Biden’s aides concealed signs of his decline and used an autopen to sign his name to executive actions.

“In recent months, it has become increasingly apparent that former President Biden’s aides abused the power of Presidential signatures through the use of an autopen to conceal Biden’s cognitive decline and assert Article II authority,” Trump wrote in a presidential memorandum signed on Wednesday. “This conspiracy marks one of the most dangerous and concerning scandals in American history.”

Biden responded with a statement Wednesday night, saying, “Let me be clear: I made the decisions during my presidency. I made the decisions about the pardons, executive orders, legislation, and proclamations. Any suggestion that I didn’t is ridiculous and false.”

CORNYN SOUGHT TESTIMONY ON BIDEN’S MENTAL HEALTH FROM BOMBSHELL BOOK AUTHORS

Meanwhile, in the Senate, Sen. John Cornyn (R-TX) revealed on Thursday he sought congressional testimony from CNN’s Jake Tapper and Axios’s Alex Thompson for a hearing later this month on Biden’s mental acuity while in office. The pair authored the Original Sin book.

Cornyn said the witness list for the hearing, which he is holding on June 18 through the Senate Judiciary Committee with fellow panel member Sen. Eric Schmitt (R-MO), is a “work in progress.”