White House spokesperson Jen Psaki said Monday afternoon that it was a "disappointing" decision, and the Justice Department will make any determinations about a legal response.
In the immediate wake of Mizelle's ruling, Psaki told reporters that the White House wasn't trying to "provoke uncertainty with passengers" by not providing an immediate response, but added that the administration continues to recommend that airline passengers continue to wear masks.
"So, we would say to anyone sitting out there -- we recommend you wear masks on the airplane and ... as soon as we can provide an update from here, hopefully soon, we'll provide that to all of you," she said.
Following the ruling, several US airlines -- Delta, United and Southwest among them -- said masks are now optional on their aircraft. In a statement, Alaska Airlines said that passengers whose behavior was "particularly egregious" over the past two years in objecting to the mandate will remain banned from flying on the airline, "even after the mask policy is rescinded."
Amtrak and the Washington Metropolitan Area Transit Authority, which operates DC's Metro, also announced that they will no longer require masks for passengers and employees, though the state-owned and operated NJ Transit and the New York Metropolitan Transportation Authority will keep their requirements.
A Biden administration official familiar with the White House's decision previously told CNN the goal of the extension was to gather more information and understanding of the BA.2 variant of the coronavirus. Covid-19 cases in the US are on the rise, leading universities
and the City of Philadelphia to reimplement indoor mask mandates.
US Surgeon General Dr. Vivek Murthy said last week that part of the reason for the extension of the transportation mask mandate was because of rising Covid-19 cases and settings created by travel.
"We bring a lot of people together in a closed setting for a prolonged period of time, and not everyone has the option to not travel," Murthy said on SiriusXM's Doctor Radio's Doctor Radio Reports, giving examples such as traveling on a plane to see a sick mother or traveling for work to keep a job. "Because it's not necessarily an optional setting for people and because, again, folks are together for a long period of time, that's why the CDC has leaned into being cautious there and recommending that people continue to wear those masks."
Judge compares enforcement to 'detention and quarantine'
The first part of the judge's 59-page ruling
turned on the meaning of the word "sanitation," as it functions in the 1944 statute that gives the federal government the authority -- in its efforts to combat communicable diseases -- to issue regulations concerning "sanitation."
Mizelle concluded that that the use of the word in the statute was limited to "measures that clean something."
"Wearing a mask cleans nothing," she wrote. "At most, it traps virus droplets. But it neither 'sanitizes' the person wearing the mask nor 'sanitizes' the conveyance."
She wrote that the mandate fell outside of the law because "the CDC required mask wearing as a measure to keep something clean -- explaining that it limits the spread of COVID-19 through prevention, but never contending that it actively destroys or removes it."
Mizelle suggested that the government's implementation of the mandate -- in which non-complying travelers are "forcibly removed from their airplane seats, denied board at the bus steps, and turned away at the train station doors" -- was akin to "detention and quarantine," which are not contemplated in the section of the law in question, she said.
As a result, the Mask Mandate is best understood not as sanitation, but as an exercise of the CDC's power to conditionally release individuals to travel despite concerns that they may spread a communicable disease (and to detain or partially quarantine those who refuse)," she wrote. "But the power to conditionally release and detain is ordinarily limited to individuals entering the United States from a foreign country."
She added that the mandate also did not fit with a section of the law that would allow for detention of a traveler if he was, upon examination, found to infected.
"The Mask Mandate complies with neither of these subsections," the judge said. "It applies to all travelers regardless of their origins or destinations and makes no attempt to sort based on their health."
Mizelle added that, additionally, the administration violated the Administrative Procedure Act, which dictates the procedures the federal government must follow when implementing certain agency policies.
The Biden administration erred in failing to seek public notice and comment on the policy, she wrote. She also ruled that the mandate violates that APA's prohibitions on "arbitrary" and "capricious" agency actions because the CDC had failed to adequately explain its reasoning for implementing the policy.
Mizelle was appointed to the federal court in late 2020 by then-President Donald Trump.
Her confirmation in the days after the 2020 election
was controversial and uniformly opposed by Democrats. A former clerk to Supreme Court Justice Clarence Thomas, Mizelle was 33 at the time of her confirmation. She had been rated
"not qualified" by the American Bar Association for "the short time she has actually practiced law and her lack of meaningful trial experience."
Previous lawsuits had failed
Other lawsuits that have been filed targeting the mandate -- and the directive to enforce it by the Homeland Security Department's Transportation Security Administration -- have failed to succeed in blocking it.
According to a Justice Department filing submitted last week
in a separate lawsuit against mandate the brought in Texas, "many other individuals have sought time-sensitive injunctive relief from the CDC or TSA orders that require masks during commercial air travel."
"The Supreme Court has thrice rejected that relief, and so has every Court of Appeals to consider the issue -- that is, the Fourth, Eighth, Eleventh, and D.C. Circuits -- as well as the U.S. District Court for the Middle District of Florida," the Justice Department said in that case, referring to an earlier lawsuit brought in Florida's Middle District. "No court has granted such relief, and not a single Judge or Justice has noted their dissent from any of these orders."
Unlike those other cases where judges were weighing emergency or preliminary orders, Mizelle was considering the legality of the mandate on the merits.
Flight attendants union urges 'calm'
In the wake of the ruling, the Association of Flight Attendants urged "calm and consistency in the airports and on planes."
"We urge focus on clear communication so that Flight Attendants and other frontline workers are not subject to more violence created by uncertainty and confusion," the union, which represents nearly 50,000 flight attendants, said in a statement.
Republicans cheered the ruling, with Florida Gov. Ron DeSantis posting on Twitter
that it was "Great to see a federal judge in Florida follow the law and reject the Biden transportation mask mandate."
Sen. Chuck Grassley, a top Republican on the Judiciary Committee, said on Twitter that the ruling
showed why his work on Trump judicial nominations was "so important to protect [individual] liberty" and "restraining [government] overreach."
Democratic Sen. Ed Markey, meanwhile, tweeted that
a "Trump-appointed judge is obstructing our pandemic response and putting the most vulnerable at risk."
This story has been updated with additional developments.
CNN's Kaitlan Collins, Dave Alsup, Chandelis Duster, Maegan Vazquez, Pete Muntean and Shawna Mizelle contributed to this report.