I agree police are funded with extorted funds, but that applies to a good deal of public services. Firemen, paramedics, schools to be sure. But also to the same extent road workers who are paid with public funds, hospitals and doctors who are reimbursed with public funds, certainly all of the military and coast guard, etc etc....
We can't equate being reimbursed with public funds with being morally compromised. The vast majority of individuals involved in the occupations I listed are good people trying to do a good job. And they are horrified when people step beyond the bounds of reason and abuse their power.
Doesn't change the fact that society would be better off if we limited the amount of occupations funded with extorted funds -- we are in agreement there.