Dr. Anthony Fauci and Sen. Rand Paul sparred Tuesday over claims that the Chinese lab where the COVID-19 virus is suspected to have emerged was doing “gain-of-function” research with funds provided by the National Institutes of Health.

Beginning his questioning by reminding Fauci that lying to Congress is a felony, Paul quizzed the White House’s top medical adviser about his testimony from a May hearing in which Fauci denied the NIH-funded gain-of-function research at the Wuhan Institute of Virology.