The Supreme Court on Friday upheld a provision of the Affordable Care Act that requires insurance companies to offer some kinds of preventive care for free.

In a 6-3 decision, written by Justice Brett Kavanaugh, the majority ruled that a federal task force that determines which preventive health measures insurance companies must cover at no cost to the insured was constitutional.

The decision appears to safeguard coverage for tens of millions of Americans who receive some free health care services, including cancer and diabetes screenings, medications to reduce heart disease and strokes, and eye ointment for newborns to prevent infections causing blindness.

Chief Justice John Roberts and Justice Amy Coney Barrett, as well as the liberal wing — Justices Sonia Sotomayor, Elena Kagan and Ketanji Brown Jackson — joined the majority opinion.

The remaining conservative justices, Clarence Thomas, Samuel Alito and Neil Gorsuch, dissented.

Mitchell Warren, the executive director of an HIV prevention organization, AVAC, praised the decision, calling its outcome a relief.

“Preventive services across health care are cost-saving and lifesaving, and I am grateful that the Supreme Court found on the side of evidence, logic, public health and human rights,” he said.

The case is the latest lawsuit targeting the Affordable Care Act, President Barack Obama’s central legislative achievement. The heath care law survived three previous major challenges at the Supreme Court, in 2012, 2015 and 2021. Roberts cast the decisive vote to save the law in 2012, a crucial milestone in which the justices upheld the law’s core mandate that most employers provide health insurance for their workers.

The dispute decided on Friday centered on the U.S. Preventive Services Task Force, a panel of experts in the Department of Health and Human Services that recommends preventive medical services, including screenings and medications to prevent serious diseases.

The task force was devised to determine preventive health services that insurance companies are required to offer for free under the Affordable Care Act.

The challenge to the task force focused on the process for selecting its members. The task force is composed of 16 volunteers, all nationally recognized experts in prevention and primary care, including family medicine, geriatrics and obstetrics.

Members are appointed by the secretary of Health and Human Services to serve four-year terms.

At issue was whether these members are legally considered “inferior” or “principal” officers. Under the Constitution, “principal officers” must be appointed by the president and confirmed by the Senate. The Affordable Care Act said the task force members and their recommendations “shall be independent and, to the extent practicable, not subject to political pressure.” The challengers argued that this made them “principal officers.”

But in the majority opinion, Kavanaugh wrote that the structure of the board makes clear that its members are subject to political control and so count as inferior officers. The secretary of health and human services can review the board’s recommendations and block them from going into effect, and can also remove the members before their terms are up.

“Task force members are supervised and directed by the secretary, who in turn answers to the president, preserving the chain of command in Article II” of the Constitution, he wrote, adding, “As a result, appointment of task force members by the secretary of HHS is consistent with the appointments clause.”

In dissent, Thomas noted that at the time the case was filed, the task force was appointed by a subordinate official in the department, a system that was since changed to elevate that power to the secretary. He added that the government had established a new statutory theory for why the current system is permissible on appeal.