Led by Florida Republican governor Ron DeSantis, twenty-one states filed a lawsuit Tuesday against the Center for Disease Control’s public transportation mask mandate.

The current CDC order, in place since February of last year, requires those traveling on “conveyances” within the United States, including airplanes, trains, and buses, to wear a mask. It also requires the wearing of masks at “transportation hubs” like airports and bus terminals. The mandate is an attempt to reduce the spread of COVID-19 within and between the states. The mandate was set to expire on March 18 but was extended by the Biden Administration until April 18.

The lawsuit alleges that the mandate exceeds the CDC’s statutory authority. It claims that the named states suffer harm due to the mask mandate, in that they must expend resources to enforce the mandate, and they are subject to criminal and civil penalties if they do not. Many of the states also have laws or policies in place that prohibit mask requirements in contexts where the federal mask mandate would apply, thereby harming the states’ “sovereign interests.”

Governor DeSantis called the federal mandate “unnecessary” and said that “It is well past time to . . . get back to normal life.” Florida attorney general Ashley Moody called the mandate “shortsighted, heavy-handed and unlawful,” and claimed that it was “causing chaos on public transportation.” The complaint asks the court to hold that the mandate is unlawful and issue a permanent injunction against its enforcement.

The states joining Florida in the complaint are Alabama, Alaska, Arizona, Arkansas, Georgia, Idaho, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Montana, Nebraska, Ohio, Oklahoma, South Carolina, Utah, Virginia, and West Virginia.