I once had a run-in with what looked to be a homeless guy, wearing a cap with CIA on it. Turns out he was actually a guy that did part-time security, and when I ignored his numerous inquiries (parked in my hotel parking lot talking on the phone) he called the cops on me. He even flashed a business card that had CIA on it. (I still ignored him).
I explained it to the cops and asked - “So how does this guy get off wearing a CIA cap!?”
They laughed. “Oh. It’s his initials. Charles L. Anderson!”
Great story! Pretty funny. The police would not be quite as understanding of a person wearing a jacket with POLlCE on it (double "L" there, second one in lowercase).