To begin with, they have no weight under U.S. law. They cite the Americans with Disabilities Act of 1989 (ADA), the Health Insurance Portability and Accountability Act of 1996 (HIPAA), and in at least one version, the Unruh Civial [sic] Rights Act. The card threatens that the bearer will report violations to the "Freedom to Breathe Agency," possibly resulting in a fine of $75,000 to $150,000.
Said agency has nothing to do with federal, state, or local government. The FTBA is just another one of those Tea Party, Proud Boys, Sinclair Broadcasting, or Rush Limbaugh's Dittohead clubs with all the legal authority of a Facebook group. The Justice Department published a notice in June regarding a version of the card displaying the Department of Justice official seal:
U.S. Attorney [Matthew G.T.] Martin urges the public not to rely on the information contained in these postings and flyers and to visit http://www.ADA.gov for official information about the Americans with Disabilities Act. For more information and technical assistance about the ADA, please contact the ADA Information Line at 800-514-0301 (voice) and 800-514-0383 (TTY).
There is, one assumes, some tiny fraction of the population who might actually have some physical limitation that prevents wearing a face mask. Having no ears, for example. Or having an allergy to all manner of cloth, which must make it difficult to get dressed in the morning. (There is also mast cell activation syndrome, but check out what this woman with MCAS is wearing.)
If you are an earless victim of MCAS, I don't mean to make your life more difficult than it already is. You might want to invest in a plastic face shield or something. As for the rest of you MAGA snowflakes, there's a good chance that this country would be on its way to getting back to normal if you'd mask up... or put a sock in it.