Health Secretary Robert F. Kennedy Jr., his son, and Senator Rand Paul have all written books criticizing Dr. Anthony S. Fauci. All were published by a company led by a close Kennedy adviser.

A few hours after Dr. Anthony S. Fauci invoked his Fifth Amendment right in refusing to answer questions from Senate Republicans last week, Health Secretary Robert F. Kennedy Jr. took to social media to plug a book he published about Dr. Fauci in 2021, declaring it “the #1 non-fiction hardcover best-seller.”

Later that day, Mr. Kennedy went on television to say much the same thing. “I wrote a book about Anthony Fauci in 2021,” he told the Fox News host Sean Hannity. “It was the biggest selling book of 2021. It sold 1.4 million copies.”

Mr. Kennedy’s mini book tour came as Republicans accused Dr. Fauci of enriching himself by enlisting staff and colleagues to enter contests with cash awards, including a $1 million prize that government ethics officials allowed him to keep. But Mr. Kennedy; Senator Rand Paul, the Kentucky Republican who chaired the hearing; and even Mr. Kennedy’s son Robert F. Kennedy III have all published critical books about Dr. Fauci whose sales may have gotten a boost from the negative public attention the men have helped generate against him.

Mr. Kennedy’s office did not respond to a request for comment on behalf of the secretary or of his son. Mr. Paul’s office also did not respond to a request for comment.

All three books are published by Skyhorse Publishing, whose founder Tony Lyons is a close adviser to Mr. Kennedy and runs a political action committee and other groups supporting the secretary’s agenda. Mr. Paul’s book was published in 2023 by Regnery Publishing, which was acquired by Skyhorse in December of that year. (Skyhorse also recently published a memoir by the actress Cheryl Hines, Mr. Kennedy’s wife.)

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