The corrupt cops like comey and mccabe have been peppering police departments with informants turned cops (criminals taken out of jail and then made into police) We have to watch out for these guys.  But mostly they are being used to compromise other dumber cops by having them beat up a teenager or commmit a rape and then filming it secretly and blackmailing them into making moves in a civil war / martial law situation, that blackmail becomes meaningless and they revert to their innate alignments