The U.S. Senate voted largely along party lines to confirm Robert F. Kennedy Jr. to run the Department of Health and Human Services (HHS), installing an anti-vaccine activist and conspiracy theorist to head a $1.8 trillion agency that oversees the nation’s largest health programs. Kennedy will also be able to shape federal abortion policy and has expressed openness to national restrictions.

Only one Republican, Mitch McConnell of Kentucky, voted against Kennedy, joining all 45 Democrats and two independents who caucus with that party. McConnell, who had polio as a child, expressed concern about Kennedy’s views on the polio vaccine. Sen. Bill Cassidy, a Louisiana Republican and physician, voted for Kennedy after publicly saying he wasn’t sure if he could back his nomination because of his views on vaccines. 

Kennedy, who has no medical or science degree, has voiced skepticism about major vaccines for years, falsely linking them to autism. He has also endorsed fringe conspiracy theories, including that wireless internet causes cancer. He backed those views again in his confirmation hearings last month.

“What will you tell the American mother?” Cassidy asked Kennedy during a key health committee hearing that focused heavily on vaccines — spotlighting the power of parents and caregivers in the debate over who will oversee HHS. “Will you tell her to vaccinate her child or to not? … Your past of undermining confidence in vaccines with unfounded or misleading arguments concerns me. Can I trust that that is now in the past? Can data and information change your opinion, or will you only look for data supporting a predetermined conclusion? This is imperative.”

Kennedy said during those hearings that he is not anti-vaccine, but then made contradictory statements to lawmakers when pressed about the settled science of their safety. At times, he declined to acknowledge the available and conclusive data that vaccines do not cause autism.

Asked by a senator if he was a conspiracy theorist, Kennedy replied that it was “pejorative … mainly to keep me from asking difficult questions of powerful interests.”

Kennedy also continued to back other fringe conspiracy theories and would not retract statements calling the human papillomavirus vaccine “dangerous and defective.” The vaccine, which is safe and effective, has led to a dramatic reduction in cervical cancer. 

He was questioned about endorsing the idea that Black people should receive vaccines at different times than White people, prompting Sen. Angela Alsobrooks, a Democrat from Maryland and one of two Black women in the Senate, to ask him, “What different vaccine schedule should I have received?” 

Kennedy will not have unilateral power to revoke vaccine mandates, but he will have authority to enact a series of changes at HHS that would ultimately affect their availability, affordability and effectiveness, according to medical experts. His confirmation may shift public perception after recent years of falling vaccination rates. 

Kennedy enters his post after a failed bid for the presidency in 2024. But his slogan, “Make America Healthy Again” — a catch-all phrase framed around addressing perceived corruption in how food and medicine are regulated — caught on with supporters. Those include wellness influencers, some of whom are mothers, who have advocated loudly for his confirmation.

At HHS, Kennedy will have major influence over abortion policy as well. After drawing opposition from some anti-abortion groups and lawmakers — some of whom pointed to his past support of access to the procedure — he indicated openness to enacting national restrictions. Kennedy said President Donald Trump wants him to look at “the safety of mifepristone,” one of two drugs used in medication abortions, which comprehensive research shows is safe and effective. 

Abortion opponents have falsely argued that the drug is dangerous, citing studies that were retracted for flawed methodology, to argue that mifepristone should be taken off the market or severely restricted. That could effectively halt access to a major method of abortion nationwide, a contradiction to Trump’s promise to leave abortion “up to the states.”

Kennedy also said he would implement Trump’s policies, including a goal to “end late-term abortion” — a term that has no medical meaning, but that some abortion opponents have sought to define as terminations after 15 weeks. (Many pregnancy-related complications, including ones that are potentially fatal for the pregnant person and fetus, are not discovered until the 15-week mark or later.)

Those remarks won him cautious plaudits from abortion opponents. 

“We are encouraged by Robert F. Kennedy Jr.’s confirmation hearings,” Marjorie Dannenfelser, head of the anti-abortion group SBA Pro-Life America, said in a statement, adding that his remarks constituted “clear answers and commitments” on anti-abortion policy goals.

Kristi Hamrick, vice president for Students for Life, called Kennedy’s remarks on mifepristone “encouraging.”

“There is a lot to discuss with the Trump administration,” she said after the first of Kennedy’s two confirmation hearings. 

Kennedy’s oversight will extend into Medicaid, the massive state-federal health care program that covers insurance for millions of low-income people, children and people with disabilities. During his hearings, Kennedy appeared to not know how parts of Medicaid work, inaccurately claiming it is fully paid for by the federal government. He also claimed the program had high premiums and deductibles, even though most recipients do not pay out-of-pocket costs. Kennedy also appeared confused about aspects of coverage for people in Medicare, the health care program available to Americans over 65 and other people with certain medical conditions.

Kennedy has also indicated that he will work to eliminate gender-affirming care, indicating he would rescind nondiscriminatory guidance from the Biden administration on gender identity, calling it “anti-science.”

“People who have gender differences should be respected. They should be loved,” he said. “Sometimes love means saying no to people.”