The Supreme Court grappled with whether the Biden administration has the power to order vaccine or masking mandates at hospitals and workplaces in a special oral argument on Friday, when the court’s own COVID-19 rules stopped two attorneys from arguing in person.

The justices are reviewing lower court orders that at least partially halted two Biden administration moves made on an emergency basis, each with their own set of legal issues.

One is an Occupational Safety and Health Administration rule for larger businesses to either require vaccines or have a masking and testing policy early this year; the other is a Centers for Medicare and Medicaid Services vaccination mandate for health care workers.

The dynamic situation around the coronavirus pandemic, with a sharply increased number of Americans testing positive among the spread of the highly contagious omicron variant, played a significant role in the arguments about whether Congress needed to more specifically authorize such mandates.

Justice Stephen G. Breyer repeatedly brought up the latest statistics on COVID-19 cases — he said nearly 750,000 cases every day — amid questions about how quickly the justices should act and how much courts should step in on public health matters.

“I mean, there are three quarters of a million new cases yesterday, new cases,” Breyer said. “That’s 10 times as many as when OSHA put this rule in. The hospitals are today, yesterday, full almost to the point of a maximum they’ve ever been in this disease.”

Over the course of more than three hours of argument, the conservative majority of the court appeared more skeptical of the broader OSHA rule than the CMS rule. The justices’ expedited hearing on these COVID-19 cases hints that they are ready to act within days.

Scott Keller, an attorney arguing for businesses that challenged the OSHA rule, told the justices that if Congress had intended to give an agency the power to mandate vaccines across the country, it needed to do so clearly.

That’s especially true for a rule that covers 1.8 million establishments and 84 million employees, or two-thirds of the private workforce, Keller said. “States can do it. Businesses have done it and are able to do it,” Keller said. “The question is not what is this country going to do about COVID, it’s who gets to decide that.”

Chief Justice John G. Roberts Jr. asked questions along that theme and questioned whether a Congress that passed the law five decades ago would have foreseen such broad mandates, while Justice Neil M. Gorsuch suggested that was a way to put in a mandate without authorization.

“Congress has had a year to act on the question of vaccine mandates already,” Gorsuch said. “As the chief justice points out, it appears that the federal government is going agency by agency as a workaround to its inability to get Congress to act.”

Solicitor General Elizabeth Prelogar, who argued for the Biden administration in the OSHA case, said Congress gave that agency statutory authority to rely on vaccine and masking measures that would save 6,500 lives and prevent 250,000 hospitalizations in just six months.

Vaccines are “not some kind of newfangled thing” because “most of us have been subjected to compulsory vaccination requirements at various points throughout our lifetime,” Prelogar said.

“And so the idea that Congress couldn’t have anticipated that in dealing with the deadliest virus that OSHA has experienced in its history, it might think that encouragement of vaccination would be an appropriate way to protect workers, I think it’s just inconsistent with the idea that vaccination is often the single most effective way to target a virus,” Prelogar said.

Justice Sonia Sotomayor, who elected to participate in the argument remotely from her chambers, pointed out that the law charges OSHA with developing innovative methods, techniques and approaches to dealing with occupational safety health issues.

“I don’t know how much clearer you can be, if you’re Congress, to tell an agency in an emergency, ‘Do what’s necessary,’” Sotomayor said.

Ohio Solicitor General Benjamin Flowers had to argue remotely because of a positive COVID-19 test from Thursday. He used that situation to point out that his situation — he’s vaccinated and boosted, and yet still contracted the novel coronavirus — showed that an OSHA mandate is not as necessary as the government contends.

“Vaccines do not appear to be very effective in stopping the spread of transmission,” Flowers told the justices. “They are very effective in stopping severe consequences, and that’s why our state strongly urges people to get them. But I think that makes it very hard to look at the numbers they give and assume that they still apply today.”

And Louisiana Solicitor General Elizabeth Murrill, who also argued remotely because of the court’s COVID-19 rules, said the vaccine requirement for health care workers went beyond the Biden administration’s power.

“Exercising this kind of power, to force the individual to submit to a medical treatment, has never, ever been something that has been authorized by Congress or done by an agency on an emergency basis,” Murrill said.

Sotomayor cut her off: “I don’t mean to interrupt you, but we’ve never had a situation like this one before. It’s unprecedented.”

Brian Fletcher, the deputy solicitor general who argued for the Biden administration in the hospital vaccine case, said if the Supreme Court leaves lower court rulings in place, then Medicare and Medicaid patients would not be protected in half the country during a pandemic.

“I don’t think anyone seriously disputes that any delay in the operation of the rule will cost lives and cause unnecessary serious illnesses,” Fletcher said.