There’s nothing wrong with a no-knock warrant–at least in theory. The cops know some bad guy is holed-up inside a house or apartment. A really bad guy. Someone they know is armed and dangerous. They talk to a judge. The cops convince the judge that the bad guy won’t give up without a fight (i.e. if they knock on the BG’s door). Unless they go in HARD—flash bangs, a squad of AR-wielding officers, the whole schmeer—the bad guy’s gonna kill him some poh-leece. In practice, the police go to the wrong address. Kill the wrong person. Shoot family pets. Not all the time. Not even most of the time. But with so damn many SWAT teams looking for something to do, bad shit happens. And so, now, when a bunch of people come storming into your house (story here) pretending to be police, what do you do? Pray that they are.