A Sheriff Boat

This is another vessel I don't see all that often.

 One of the things about Michigan is that there are many bodies of water and as such many of the police forces have to maintain a group of boats.  The Sheriff's are left out of this.

I think he was out patrolling because I saw him pull over someone on a Jet Ski.  I'm guessing the area near Milliken is a no wake area or something.