And what is the system/structure that's the problem? The entire institution of policing. The very act of policing and using force to coerce behavior and preserve the status quo. The entire C in ACAB is "the system" that's the problem. Would you rather we just said that the problem is capitalism? It isn't. Proto-police were a problem under feudalism as well. I'd say that the existence of a violence-wielding class that preserves and enforces the status quo is far more toxic to human flourishing than any other system or structure in existence.