> If I were to send an illegal demand to someone (like say a threat of blackmail / extortion), The distinction is that blackmail and extortion are crimes. It'

> If I were to send an illegal demand to someone (like say a threat of blackmail / extortion), The distinction is that blackmail and extortion are crimes. It's the act of sending them itself that is the crime, not the demand. If you withdraw it, it doesn't matter, because the crime already happened. There's no criminal statute here. The NYPD asked for something. Someone challenged it as being "not something the NYPD is allowed to ask for". The NYPD said "never mind, you're right". That's the end of the story. If you want the law granting the NYPD the power to issue subpoenas to be withdrawn or modified, the solution is to elect representatives to do that for you. Courts are just the backstop for this process, and an imperfect one.