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Ex-President Joe Biden's former chief of staff ignored reporters on his way out of an interview with congressional investigators on Thursday after a marathon grilling behind closed doors.
Ronald Klain served as White House chief of staff for the first half of Biden's term. He also reportedly played a key role in helping the former leader prepare for what proved to be a disastrous first and only 2024 election debate against current President Donald Trump.
Klain sat with staff and some lawmakers on the House Oversight Committee for hours for a voluntary transcribed interview.
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Former White House Chief of Staff Ron Klain appeared before House investigators on Thursday. (Andrew Harrer/Bloomberg via Getty Images)
Committee Chair James Comer, R-Ky., is investigating whether Biden's top White House aides concealed signs of mental decline in the then-president, and if that meant executive actions were signed via autopen without his knowledge.
Lawmakers who briefly attended the interview, however, called him "credible."
"I think he is telling what he knows accurately," Rep. Andy Biggs, R-Ariz., told Fox News Digital.
On the other side of the aisle, Rep. Ro Khanna, D-Calif., told reporters, "He answered every single question. He was fully cooperative."
House Oversight and Accountability Committee Chair James Comer is leading the probe. (Anna Moneymaker/Getty Images)
Klain is the sixth former Biden administration aide to appear for Comer's probe and the third to appear voluntarily.
Former White House physician Kevin O'Connor, as well as senior advisors Annie Tomasini and Anthony Bernal, all appeared under subpoena.
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L-R: Ian Sams, former special assistant to the president and senior advisor in the White House Counsel’s Office; Andrew Bates, former deputy assistant to the president and senior deputy press secretary; former White House press secretary Karine Jean-Pierre; and, Jeff Zients, former White House chief of staff, are expected to sit down with House Oversight Committee investigators behind closed doors. (Fox News)
Each also pleaded the Fifth Amendment to avoid answering questions.
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Longtime Biden aide Ashley Williams and former staff secretary Neera Tanden both appeared voluntarily.
Like the previous five before him, the longtime Democratic operative did not answer questions from reporters either before or after his interview.
Elizabeth Elkind is a politics reporter for Fox News Digital leading coverage of the House of Representatives. Previous digital bylines seen at Daily Mail and CBS News.
Follow on Twitter at @liz_elkind and send tips to elizabeth.elkind@fox.com