Former Biden chief of staff Jeff Zients testifies in probe of Biden mental decline

Former White House chief of staff Jeff Zients testified behind closed doors at length about former President Joe Biden’s aging throughout the course of his term, including how he pushed Biden’s doctor to conduct a full medical workup, according to a person familiar with the transcribed interview.

Zients told House Oversight Committee investigators on Thursday that Biden’s decision-making slowed during the course of the administration and that the former president’s difficulty remembering dates and names worsened over time, the person told CNN.

The interview was part of the Republican-led panel’s ongoing investigation into Biden’s mental decline, where investigators have spoken to a number of Biden’s closest former aides.

After Biden’s disastrous debate performance last year, Zients shared that he recommended Biden’s doctor, Dr. Kevin O’Connor, give a full medical workup, including a cognitive exam, and O’Connor said he would take the suggestion under advisement, the individual shared.

Zients declined to comment to CNN on the testimony.

O’Connor declined to answer questions during his deposition in front of the committee in July.

Ahead of the debate, Zients, according to the person familiar with his testimony, said Biden had a cold but had never observed him act the way he did on stage, including “mental freezes.”

Following the debate, Zients testified he and other Biden advisors believed that Biden should exit the race, according to the person familiar.

Former first lady Jill Biden spoke with Zients about ensuring the then president got more rest and was not overscheduled, the person said of Zients’ testimony.

Zients also shared that he discussed Biden’s age issues with other former aides whom the House Oversight Committee has interviewed, including Annie Tomasini and Anthony Bernal, who both pled the 5th Amendment in their separate interviews, the person shared.

A separate source told CNN that Zients made clear in his testimony that he saw his job as ensuring that Biden met with a range of advisers to thoroughly consider issues so that he could make the best decisions, but ultimately Biden made the final decisions alone.

The second source told CNN that Zients also articulated that he had full confidence in Biden’s ability to serve as president.

CNN’s Jake Tapper contributed to this report.