Anthony Fauci, the former leading US infectious disease authority, declined to respond to queries during a Senate session on Wednesday. He cited his constitutional protection against self-incrimination and described Republican Senator Rand Paul’s efforts as an unhinged drive to see him jailed.

Fauci, who is 85 and stepped down in 2022, received a subpoena from Paul of Kentucky, who leads the Senate Homeland Security and Governmental Affairs Committee and has long opposed him. The retired official blamed Paul for an unhinged campaign aimed at his imprisonment and declined to address more than 100 questions.

Paul stated that Fauci could not invoke the Fifth Amendment to avoid senators’ questions, that a pardon from former President Joe Biden offered no shield, and that refusal to answer would bring consequences. He added that the committee planned a vote next week to hold Fauci in contempt.

Fauci directed the National Institute of Allergy and Infectious Diseases for 38 years under both Republican and Democratic presidents and served as the public face of the US pandemic response. He has drawn sharp criticism from President Donald Trump and many conservatives. Trump posted on social media before the hearing that Fauci’s ideas were crazy.

More than 1.1 million Americans died from COVID-19, sparking a sustained conservative effort to assign blame for measures taken to curb the crisis. Fauci became the main target, facing attacks over lockdown rules, mask and distancing guidance, and vaccine promotion, even though the shots proved safe and effective.

He and other public health leaders worldwide backed those steps on the basis of evidence available then to slow a new deadly virus until vaccines arrived.

Biden issued a preemptive pardon for Fauci on January 19, 2025, to prevent unjustified and politically driven prosecutions tied to COVID or the response. The pardon excludes later actions.

Republicans Fault Fauci for Silence

Federal law criminalizes knowingly false statements to Congress, which could expose Fauci to prison if prosecutors found he lied after the pardon.

Republicans faulted Fauci for his refusal and pointed to federal law plus a 19th-century Supreme Court ruling that they said required his testimony.

The 1896 decision permits Congress to compel testimony by granting immunity from prosecution for statements made, without breaching Fifth Amendment protections.

Fauci even pleaded the Fifth when Senator Josh Hawley asked the date and the colors of his tie and the carpet. Ohio Senator Bernie Moreno pressed repeatedly for an apology to groups he blamed Fauci for harming through pandemic policies.

Paul ordered the removal of Fauci’s lawyer David Schertler after the attorney tried to speak.

Schertler later called Paul’s pursuit an obsessive vendetta and said the claims were false and disgraceful, adding that all options would be examined to hold him accountable.

Paul has long sought Fauci’s indictment and accused him of lying to Congress about National Institutes of Health funding for virus research in Wuhan, China, and of covering up the origins of COVID.

Fauci Rejects Paul’s Slanderous Remarks

Fauci denies both accusations and notes he has testified truthfully before Congress on these topics, often with Paul as his main critic.

Fauci said Paul’s obsession with prosecution, his slanderous comments, and the release of his unredacted personal diary showed the hearing aimed only to force statements that would support Paul’s pledges to imprison him.

Michigan Senator Gary Peters, the committee’s senior Democrat, called the hearing biased and one-sided, describing it as an attempt to justify a conclusion reached years earlier.

Claims about gain-of-function research in China have fueled many accusations about COVID origins. The term generally refers to altering a pathogen to increase transmissibility or danger.

Paul has long claimed the National Institutes of Health funded such work in Wuhan and that Fauci lied in denying it, while Fauci maintains the research did not meet the government’s formal definition.

COVID Origins Still Unclear

COVID origins remain unsettled. The FBI stated in 2023 that a leak from a Wuhan lab likely started the pandemic, a claim China dismissed as lacking credibility. The CIA said in January 2025 a lab leak was probable but with low confidence, while four other US intelligence agencies and the National Intelligence Council assess the virus most likely arose through natural animal transmission.

Paul this week released a 1,141-page collection of Fauci’s pandemic-era diary entries from December 2019 through December 2022, claiming they undermine the official narrative.

A review supplied by a Fauci representative found the entries aligned with his public statements at the time. Fauci has said since 2021 that he kept an open mind about a possible lab leak and spoke early in 2020 about asymptomatic spread and China’s lack of transparency, the same points Paul says the diary exposes.

The entries mainly record Fauci’s media appearances and growing public profile.

The Trump administration issued a policy on Tuesday barring federal funding for dangerous gain-of-function research.