My theory is that the compromised people get promoted to leadership so the rest of the force has black mail on them in case they try to enforce something on them and that you have to be a 'made man' who has shown to follow the G-code and be in on doing crimes to be promoted to police leadership and supervision positions.. that is why they voted Patrick Rose to represent them in the union and provide legal and political protection. His thing was molesting teenagers, but I am guessing he would provide protection for cops whose thing was theft, sexual harassment, assault or whatever.