Controversial Health and Human Services nominee Robert F. Kennedy Jr. was back on Capitol Hill Thursday morning to answer more questions from various senators as he attempts to secure the secretary position.

Robert F. Kennedy Jr. spent two days this week insisting to senators that he’s not anti-vaccine. He said that he instead supports vaccinations and will follow the science in overseeing the $1.7 trillion Department of Health and Human Services, which, among other duties, oversees vaccine research, approval and recommendations.

For the first time in modern American history, a skeptic of medical research could be responsible for safeguarding public health.

Robert F. Kennedy Jr. faced aggressive questions about his skepticism of vaccines and other issues during the first of two scheduled Senate confirmation hearings.

If approved, Kennedy will control a $1.7 trillion agency that oversees food and hospital inspections, hundreds of health clinics, vaccine recommendations and health insurance for roughly half the country.

The hearings were packed to capacity with protesters and fans, while the spillover crowd hung out in hallways and overflow rooms.