The Supreme Court on Friday turned down a request from a group of Maine health-care workers to block a state coronavirus vaccination mandate that does not contain an exception for religious objectors.

Three conservative justices dissented from the decision. While the majority did not give a reason for denying the request, Justice Neil M. Gorsuch wrote that the workers deserved an exemption.

“No one questions that these individuals have served patients on the front line of the COVID-19 pandemic with bravery and grace for 18 months now,” wrote Gorsuch, who was joined by Justices Clarence Thomas and Samuel A. Alito Jr.

“Yet, with Maine’s new rule coming into effect, one of the applicants has already lost her job for refusing to betray her faith; another risks the imminent loss of his medical practice.”

The court twice before has refused to step in regarding vaccination requirements — Justice Amy Coney Barrett rejected a request from Indiana University students and Justice Sonia Sotomayor declined to halt a New York City mandate for public school teachers. Neither justice provided a reasoning.

But both the university and the school system provided a religious exemption.

Nine pseudonymous health-care workers asked the court to block a requirement that they be vaccinated by Friday to keep their jobs. Represented by the religious legal organization Liberty Counsel, the workers said Maine was an “extreme outlier” in allowing only a medical exception for refusing the vaccine, and not an additional one based on religious objection, as they said 47 other states have done.

“Almost every other state has found a way to protect against the same virus without trampling religious liberty — including states that have smaller populations and much greater territory than Maine,” they said in their request to the Supreme Court.

“If Vermont, New Hampshire, Alaska, the Dakotas, Montana, Wyoming, California, and the District of Columbia can all find ways to both protect against COVID-19 and respect individual liberty, Maine can too.”

The other states without religious exemptions, it said are Rhode Island and New York, although New York’s has been blocked for now.

The Supreme Court’s liberal justices, along with Chief Justice John G. Roberts Jr., have generally been content with allowing local officials to set rules for vaccinations and other emergency requirements related to the pandemic.

Barrett has joined the conservatives when religious issues have been at stake.

But she wrote separately in the Maine case to say she was not sure relief was warranted, and the court should not make such a decision “on a short fuse without benefit of full briefing and oral argument.”

Joined by Justice Brett M. Kavanaugh, she said that was not what the court’s emergency docket should be used for.

“In my view, this discretionary consideration counsels against a grant of extraordinary relief in this case, which is the first to address the questions presented,” she wrote.

The court lately has come under intense criticism in Congress and elsewhere for making important decisions in the “shadow docket.

A federal district court and a panel of the U.S. Court of Appeals for the 1st Circuit said Maine’s requirements were allowable because they were not aimed at religious exercise.

The appeals court said the state had three good reasons for the health-care worker requirement: ensuring workers remain able to provide needed care in an overburdened health-care system, protecting the health of those most vulnerable to the virus, including those who could not take it for medical reasons, and “protecting the health and safety of all Mainers, patients and health-care workers alike.”

“In confronting the various risks to its own population and its own health-care delivery system, Maine’s rule does not violate the Constitution,” the panel said.

Maine has required vaccination of certain workers against some diseases since 1989, the state said.

It previously allowed exemptions for religious and philosophical reasons. But in 2019, concerned about falling vaccination rates in the states, it eliminated those exemptions for health-care workers, day-care employees, schoolchildren and college students. A subsequent referendum on the action was approved by nearly 75 percent of the state’s voters.

In August, it added coronavirus vaccines to the list of those required and gave workers until Oct. 29 to get immunized.

“The Legislature’s elimination of all nonmedical exemptions was intended to increase the overall rate of vaccination and protect individuals who are unable to be vaccinated for medical reasons,” Maine Attorney General Aaron M. Frey said in a filing to the court. “Neither the Rule nor the Statute can be said to be directed at religious practice.”

But the workers argued that requiring vaccination of some but not others means the requirement is not neutral.

“Since Maine has found a way to accommodate all medical objections to the vaccine, it must extend those accommodations to sincere religious objectors like Plaintiffs,” Liberty Counsel lawyer Mathew D. Staver. “It cannot be that only those with religious objections must be kicked out of their livelihoods, while other unvaccinated employees are welcome to stay on-site.”

He also noted that the Equal Employment Opportunity Commission (EEOC) recently weighed in on the issue and the requirements of federal civil rights laws.

“The EEOC reaffirmed guidance that Title VII requires an employer to ‘thoroughly consider all possible reasonable accommodations’ for religious objectors to COVID-19 vaccinations, and that ‘in many circumstances, it may be possible to accommodate those seeking reasonable accommodations for their religious beliefs.’ ”