Robert F. Kennedy Jr. has said vaccines are not safe. His support for abortion access has made conservatives uncomfortable.

When the leaders of Meta, Google, Amazon and Apple were spotted together at church on the morning of Donald Trump’s inauguration, it was no accident.

The recent Senate confirmation hearings for Robert F. Kennedy Jr. presented a striking scene that would confuse a time traveler from 10 years ago. Democratic lawmakers took turns excoriating a man who once embodied their ideals. Sen. Bernie Sanders, seemingly grasping for gotchas, was reduced to questioning Kennedy about baby clothing merchandise.

Robert F. Kennedy Jr.’s nomination to be the nation’s top health official is uncertain after a key Republican joined Democrats to raise persistent concerns over the nominee’s deep skepticism of routine childhood vaccinations that prevent deadly diseases.

The issue isn’t only his troubling views but whether a complex federal agency can function effectively under his leadership.

In a contentious confirmation hearing to become the nation’s top health official, Robert F. Kennedy Jr. struggled Wednesday to answer questions about Medicare and Medicaid, programs that affect tens of millions of Americans,

Alexandra Sifferlin, a health and science editor for Times Opinion, hosted an online conversation on Wednesday with the Opinion columnist Zeynep Tufekci and the Opinion writers David Wallace-Wells and Jessica Grose about Robert F. Kennedy Jr.’s first of two confirmation hearings for secretary of health and human services.

As Robert F. Kennedy Jr. faced skeptical senators Thursday in the second day of his confirmation hearing to lead the department of Health and Human Services, Sen. Bill Cassidy confronted Kennedy about vaccines.

Robert F. Kennedy Jr. said he wasn’t antivaccine as senators pressed on his past remarks, in the first of two days of hearings over his nomination for health secretary.

Tulsi Gabbard, Kash Patel and Robert F. Kennedy Jr. are among Trump's more controversial nominees, and faced tough questions from senators Thursday.

Robert F. Kennedy Jr., the nominee to lead the Department of Health and Human Services, made disputed claims before the Senate Committee on Health, Education, Labor and Pensions.

Kennedy’s bid to serve as America’s top health official may be decided by a handful of Republicans, including several senators who questioned him Thursday.