Former US health official Anthony Fauci invoked his Fifth Amendment right during a contentious US Senate hearing on the origins of Covid-19, declining to answer questions from lawmakers over concerns that his testimony could be used against him in a future perjury case.
Fauci, the former director of the National Institute of Allergy and Infectious Diseases, said the decision was made on the advice of his legal team, arguing that repeated calls by Republican lawmakers for his prosecution created the risk that any statement could be used against him.
The hearing, led by Senator Rand Paul, focused on the origins of the pandemic and the US government's response, but Fauci's refusal to testify resulted in a prolonged partisan confrontation rather than new factual findings.
In his opening statement, Fauci said Senator Paul had an "obvious obsession" with prosecuting him and argued that the hearing was intended to pressure him into making statements that could later be used in criminal proceedings.
Throughout the hearing, Fauci repeatedly responded that, on the advice of counsel, he was invoking his constitutional right to remain silent.
Republican senators criticised Fauci's pandemic-era guidance, including shifting public health recommendations, and questioned his previous statements regarding Covid-19's origins.
Paul said the committee would vote next week on a resolution to hold Fauci in contempt of Congress following his refusal to answer questions.
During the proceedings, Fauci's lawyer, David Schertler, attempted to address the committee but was removed from the hearing room after repeated interruptions.
Democratic senators defended Fauci, arguing the hearing was structured to expose him to potential perjury charges rather than obtain new information.
They warned that targeting public health officials in this manner could discourage scientific experts from serving in government during future crises.
President Donald Trump also commented during the hearing, criticising Fauci's handling of the pandemic and reiterating his longstanding view that Covid-19 originated from a laboratory in Wuhan, China.
The origins of the virus remained a central point of dispute during the hearing, with Republican lawmakers continuing to promote the lab-leak theory while Fauci's previously released diary entries showed he initially considered both natural and laboratory-origin possibilities before later expressing greater confidence in a natural origin.
Following the hearing, Florida's attorney general announced an investigation into Fauci, while Republican lawmakers signalled further efforts to compel his testimony.