The police union doesn't normally direct the police department. That is the job of a state or city employee. The union is there as a mediator between the cops and the city/state.
If the police union is literally in charge of the police.. then that is the dumbest idea ever. Who made that change?
Ever creative trying to paint people in corners with your stupid assumptions. Antifa is a cause, some who believe in it are noble and others are batshit crazy or even violent, but it's still isn't an organization. That your labeling everyone you don't agree with as being affiliated to serve your narrow political agenda is as silly as it is ignorant