I think Jeeps is right...state to state is different
Here in Michigan, they can sit in the dark, behind a fat wife, or whatever they want. I had to bounce when I blew past a state popo on the highway at like 85 in a 55 on my bike. He was sitting in the dark under a overpass.
As far as markings... here in Michigan I believe they have to have at least one side of the car marked. Many new cars have the black reflective tape on the one side on the black car. Can't see it during the day and it is usually on the side that isn't facing you at night. They don't need front or rear markings. It gets pretty tricky....
Not to mention they have crown vics, impalla's, intrepids, chargers, and a few others.
aka Gas Man
Was: 2002 Kaw ZX-9R
is me till the