A federal appeals court on Saturday temporarily halted the Biden administration’s vaccine requirement for businesses with 100 or more workers.

The 5th U.S. Circuit Court of Appeals granted an emergency stay of the requirement by the federal Occupational Safety and Health Administration that those workers be vaccinated by Jan. 4 or face mask requirements and weekly tests.

Louisiana Attorney General Jeff Landry said the action stops President Joe Biden “from moving forward with his unlawful overreach.”

“The president will not impose medical procedures on the American people without the checks and balances afforded by the constitution,” said a statement from Landry, a Republican.

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The U.S. Labor Department’s top legal adviser, Solicitor of Labor Seema Nanda, said the department is “confident in its legal authority to issue the emergency temporary standard on vaccination and testing.”

OSHA has the authority “to act quickly in an emergency where the agency finds that workers are subjected to a grave danger and a new standard is necessary to protect them,” she said.

A spokesman for the Justice Department, Anthony Coley, said in a statement: “The OSHA emergency temporary standard is a critical tool to keep America’s workplaces safe as we fight our way out of this pandemic. The Justice Department will vigorously defend this rule in court.”

Such circuit decisions normally apply to states within a district — Mississippi, Louisiana and Texas, in this case — but Landry said the language employed by the judges gave the decision a national scope.

“This is a great victory for the American people out there. Never before has the federal government tried in a such a forceful way to get between the choices of an American citizen and their doctor. To me that’s the heart of the entire issue,” he said.

At least 27 states filed lawsuits challenging the rule in several circuits, some of which were made more conservative by the judicial appointments of President Donald Trump.

The Biden administration has been encouraging widespread vaccinations as the quickest way to end the pandemic that has claimed more than 750,000 lives in the United States.

The administration says it is confident that the requirement, which includes penalties of nearly $14,000 per violation, will withstand legal challenges in part because its safety rules preempt state laws.

The 5th Circuit, based in New Orleans, said it was delaying the federal vaccine requirement because of potential “grave statutory and constitutional issues” raised by the plaintiffs. The government must provide an expedited reply to the motion for a permanent injunction Monday, followed by petitioners’ reply on Tuesday.

Lawrence Gostin, a professor at Georgetown University Law Center and director of the World Health Organization’s center on global health law, said it was troubling that a federal appeals court would stop or delay safety rules in a health crisis, saying no one has a right to go into a workplace “unmasked, unvaxxed and untested.”

“Unelected judges that have no scientific experience shouldn’t be second-guessing health and safety professionals at OSHA,” he said.