In Murphysboro city limits, there is a city ordinance saying that you must wear a mask in public. I have not personally seen them enforce it yet. But, Wal-Mart is private property. If someone decides not to wear a mask to their store, they do not have to let you in the doors, and can make you leave, or call the police to have you ejected and trespassed from the property.
No
It's not LAW, just decent.
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