Both State and Charlevoix County Police will drive up behind you with no lights at a high rate of speed in an attempt to make you nervous so you pull over and then they will pull you over. It has happened to me personally with a white unmarked County patrol car and several friends have mentioned it happening to them also. This is probably illegal since they should have lights and siren on when traveling at a high rate of speed. They will get right on your rear bumper and I consider this a very dangerous practice.