WASHINGTON — It’s a tone not typically taken in the august chambers of the U.S. Senate — except when Anthony Fauci and Sen. Rand Paul square off.

The two men — the country’s top infectious-disease doctor and the Republican senator from Kentucky — have a history of heated exchanges and escalating accusations, with Paul often using the congressional hearings to inveigh against Fauci over his handling of the coronavirus pandemic and Fauci responding with an increasingly vigorous defense.

On Tuesday, they traded their most barbed public remarks yet, accusing one another of lying during a fierce debate over U.S. funding for a lab in Wuhan, China.

“Senator Paul, you do not know what you’re talking about, quite frankly, and I want to say that officially.” Fauci, director of the National Institute of Allergy and Infectious Diseases, said at one point. “You do not know what you are talking about.”

The argument, which echoed an earlier dust-up, centered on Paul’s claim that the the National Institutes of Health awarded a grant that partially funded a project that relied on “gain-of-function” research, a controversial practice that involves enhancing a virus in a lab to try to anticipate future pandemics. This type of experimentation has come under growing scrutiny as U.S. intelligence agencies investigate the origins of the virus and the theory that it could have accidentally leaked from a lab.

Officials have repeatedly denied Paul’s allegations, and in a May hearing, Fauci told the senator that the NIH “has not ever and does not now fund gain-of-function research” at the Chinese lab, the Wuhan Institute of Virology.

On Tuesday, Paul suggested Fauci had lied: “Dr. Fauci, knowing that it is a crime to lie to Congress, do you wish to retract your statement of May 11 where you claimed that the NIH never funded gain-of-function research in Wuhan?” Paul asked.

“Senator Paul, I have never lied before the Congress, and I do not retract that statement,” Fauci replied, adding that the research had been “judged by qualified staff up and down the chain as not being gain-of-function.”

Paul then accused Fauci of “dancing around this because you are trying to obscure responsibility for four million people dying around the world from a pandemic.”

“I totally resent the lie that you are now propagating, senator,” Fauci shot back.

The Washington Post’s Fact Checker examined Paul’s previous claim that Fauci had overseen NIH funding of gain-of-function research in Wuhan and found it to be exaggerated and misleading, awarding it “Two Pinocchios.”

On Tuesday, Fauci went further.

“You are implying that what we did was responsible for the deaths of individuals,” he said. “I totally resent that. And if anybody’s lying here, senator, it is you.”

Fauci has been the target of right-wing opprobrium since the earliest days of the pandemic, with conservatives calling for his ouster and for a criminal investigation into his conduct. Earlier this month, Florida Gov. Ron DeSantis’s campaign printed shirts and koozies reading “Don’t Fauci My Florida.” But for more than a year, Paul has fashioned himself as the Senate’s chief Fauci skeptic, and his attacks have grown more and more personal.

In a March hearing, Paul pressed Fauci on recommendations that people who have been vaccinated or have contracted the virus should wear masks.

“You’ve had the vaccine, and you’re wearing two masks,” Paul said. “Is that just theater?”

“Here we go again,” Fauci responded.

Only subscribers are eligible to post comments. Please subscribe or to participate in the conversation. Here’s why.

Use the form below to reset your password. When you've submitted your account email, we will send an email with a reset code.

Daily Headlines

  • Sign up and get the top stories to begin the day delivered to your inbox at 6 a.m.