There's a woman going around claiming to be from the federal "Freedom to Breathe Agency", telling store workers that they can personally be sued for telling customers that they need to wear a mask.
Multiple people have said that she should be arrested for impersonating a federal officer. However, 18 U.S. Code § 912 - Officer or employee of the United States says:
Whoever falsely assumes or pretends to be an officer or employee acting under the authority of the United States or any department, agency or officer thereof, and acts as such, or in such pretended character demands or obtains any money, paper, document, or thing of value, shall be fined under this title or imprisoned not more than three years, or both.
IANAL, but I don't think tricking an employee into believing that they can be personally sued for asking a customer to wear a mask counts as "thing of value".
So what does "act as such" mean when the person claims to be from a non-existent agency? Since there isn't any federal Freedom to Breathe Agency, there doesn't exist any way that an employee of it would act.
(NOTE: The woman claiming to be from the "Freedom to Breathe Agency" might very well have committed other crimes. I'm solely asking about the crime of impersonation.)