'Original Sin' co-author exposes 'frantic efforts' to hide Biden's cognitive decline

Members of former President Joe Biden's inner circle "weren't telling the truth" when describing him as "sharp," "focused" and "detail-oriented," Axios national political correspondent Alex Thompson said Sunday - adding that the media fell short in challenging the narrative.

The co-author of the new book "Original Sin," which details what many view as a calculated, years-long effort to conceal the former president's decline in the run-up to the 2024 election, joined "Fox News Sunday" to shed light on the inner workings of the Biden White House. 

"They weren't telling the truth, and I think the book really conclusively shows what was going on behind the scenes," he said, weighing in on a series of statements from top Biden officials - including then-Homeland Security Sec. Alejandro Mayorkas, former press secretary Karine Jean-Pierre and former Chief of Staff Ron Klain - who, at various times, portrayed Biden as intellectually sharp and fully in control. 

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Jean-Pierre even dismissed "right-wing critics" by blaming "cheap fake" videos and selectively edited media.

But, according to Thompson, the reality behind closed doors told a different story.

"Throughout 2023 and 2024, there were steps taken to increasingly shield Joe Biden - not just from the public, but from members of his own cabinet, members of his own senior staff," he said.

"One White House official who left in 2024 told us that they left in part because they were not comfortable with how they were trying to shield the extent of the decline."

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Thompson said Biden's condition became harder to conceal as time went on, and the now infamous debate performance against then-candidate Donald Trump in June 2024 shattered any remaining illusions.

"The Joe Biden that people saw on that debate stage… I think the book really shows it was not the first time that Joe Biden had acted like that. You can also listen to the tapes from the Robert Hur investigation. I think you can sort of hear 'debate Biden,' and there were increasingly frantic efforts to make sure that the public did not see 'debate Biden' while the public did see that he was aging," he continued.

Thompson said Biden's debate performance was likely a "shock" to millions of Americans who finally saw the "extent" of the slippage.

Fox News Digital has written extensively dating back to the 2020 presidential campaign about former President Joe Biden's cognitive decline and his inner circle's role in covering it up.