The Centers for Disease Control and Prevention on Wednesday asked the Justice Department to appeal a federal judge’s ruling overturning the federal mask mandate for airlines and other forms of public transportation, setting up a legal battle that could permanently impact the CDC’s ability to weigh in on public health issues.

In a statement put out around 6 p.m. Wednesday, the agency said “it is CDC’s continuing assessment that at this time an order requiring masking in the indoor transportation corridor remains necessary for the public health.” A Justice Department spokesman said on Twitter that the department had filed notice of appeal.

“CDC will continue to monitor public health conditions to determine whether such an order remains necessary,” the statement read. “CDC believes this is a lawful order, well within CDC’s legal authority to protect public health.”

The mask mandate, first imposed in January 2021, has been extended repeatedly, most recently April 13 through May 3.

Days after the most recent extension, U.S. District Judge Kathryn Kimball Mizelle struck it down, arguing that requiring passengers to wear masks on public transportation ”exceeds the CDC’s statutory authority” and “violates the procedures required for agency rulemaking.”

Mizelle also argued that mask mandates didn’t meet the definition of “sanitation” as defined in the 1944 Public Health Service Act.

That law said the government can provide for “inspection, fumigation, disinfection, sanitation, pest extermination, destruction of animals or articles found to be so infected or contaminated as to be sources of dangerous infection to human beings, and other measures, as in [the government’s] judgment may be necessary.”

The CDC’s decision to proceed could have widespread impact. While a district court decision is not considered binding in other courts, any appeal would go through the Atlanta-based 11th U.S. Circuit Court of Appeals, a conservative-leaning court with jurisdiction over Georgia, Alabama and Florida.

Beyond that, it would face a conservative-leaning Supreme Court, which has expressed skepticism over some Biden-era pandemic measures.

‘Frontal attack’

Law professors have sharply criticized the ruling, saying it would hamstring the administrative state by essentially allowing judges to weigh in on every nuance of administrative law and forcing Congress to do the overwhelming bulk of the bureaucratic work that administrative agencies currently do.

“This opinion is a frontal attack on the modern administrative state,” said Alan Rozenshtein, an associate professor of law at the University of Minnesota. “The mask mandate is the least of it.”

The ruling, said Rozenshtein, takes an “incredibly narrow approach” to the CDC’s administrative authority, imposing an “incredibly restrictive view” that makes it unclear what the agency can do to protect public health.

To not appeal the decision “is to let this hang out, is to say this is valid law,” he said, adding, “The problem is you’re doing it to defend a policy that most Americans are deeply tired of.”

Still, the decision comes with risk for the Biden administration. The current mask order was set to expire May 3, the midterm elections are seven months away, and Democratic governors in a handful of states lifted their mask mandates months ago.

While COVID-19 cases are surging in parts of the country because of the BA.2 omicron subvariant, the U.S. overall is dealing with much lower levels of COVID-19 now than it did earlier in the pandemic. The subvariant, while highly contagious, appears to be less severe than omicron and has not led to dramatic increases in hospitalizations or deaths.

Eric Segall, a professor at the Georgia State University School of Law, said the political implications of fighting the decision undoubtedly weigh on the administration.

“You’d rather have a nonbinding District Court opinion in the 11th Circuit than a legally binding opinion in the 11th Circuit,” he said.

James G. Hodge Jr., a law professor at the Sandra Day O’Connor College of Law at Arizona State University, suggested an appeal would be worthwhile.

“I think the 11th Circuit might come down with a more reasoned judgment and assessment consistent with CDC authority,” he said, adding, “I think the risks are worth taking.”

To not act, he said, could open the door to undermining the CDC’s power long term. “It would be perverse just leaving this opinion to remain unchallenged,” he said. “At least challenging it — even if the CDC drops its own order before the 11th Circuit takes the case — at least then you’re on the record as requesting to appeal it.”

Ariel Cohen contributed to this report.