Yes. I read something about a library that had a sign up, "No government agents have been here." They would take down the sign during an investigation. Any one

Yes. I read something about a library that had a sign up, "No government agents have been here." They would take down the sign during an investigation. Any one who knew the sign -was- there knew an investigation was underway. No gag order was broken. There is a name for this type of flag, but don't know it off hand.