The Freedom Foundation, a conservative nonprofit, today filed a motion asking the Oregon Court of Appeals to block Gov. Kate Brown's statewide mask requirement.

"Governors in left-leaning states all over the country are making up the rules as they go—and ignoring the procedural rules their own state laws set up," said Jason Dudash, the foundation's Oregon director, in a statement.

The group, which is active in California, Oregon, Washington, Ohio and Pennsylvania, filed a similar challenge in Washington earlier this month. The Freedom Foundation regularly battles public employee unions on legal matters but has recently expanded its interests.

Today's filing on behalf of three Oregonians—two of whom say they can't wear masks for health reasons and one because he disputes the governor's right to tell him to wear one—asks the court to stay Brown's order for 21 days.

On July 13, in response to the rapidly escalating number of COVID-19 cases in the  state, Brown announced what she called a new "requirement" for masks in common indoor spaces.

"We need to do absolutely everything we can to reduce transmission in ways that do not require us to close down businesses again," Brown said then. "The proof here will be in the numbers. Either people will adhere to this requirement and be a positive force for stopping COVID-19, or I will be forced to take more restrictive measures."

The Freedom Foundation's argument is that Brown's requirement and her earlier guidance, which was less prescriptive, were imposed without following procedures laid out in Oregon law and that they violate Oregonians' state and federal constitutional rights.

"Petitioners' important constitutional rights are at stake," the Freedom Foundation motion says. "Their rights are being infringed and limited ostensibly under the motivation to protect others. However, the State, nor [the Oregon Health Authority] can simply ignore the state statutes that apply to their rulemaking, nor the constitutional protections afforded to Oregonians."

Brown's spokesman, Charles Boyle, declined to comment on the motion.

"But what I can say is that face coverings save lives," Boyle said in a statement. "The virus is transmitted through droplets that come from your nose and mouth. Face coverings protect you, your friends, and neighbors from contracting this deadly disease. And the more people who wear face coverings while out in public, the more likely it is that we can keep businesses open."