So, how did the librarian get the word out? By regularly reporting to the library board that no NSL had been issued to any of the cityâ€™s 10 branches, which was perfectly legal. Everyone knew that if the chief librarian failed to report that nothing had happened, then indeed an NSL had been served.
[From Privacy Work-Around]
Sometimes the brilliance of the common sense of librarians is amazing. Given tight legal restrictions, they read the law, and found a solution that was compatible and in the end worked for their library