While traveling in the Southwest, I saw in two different occasions police cars that were painted all black, with no writing or logos on them. One was an older style of police car, the other was a muscle car that looked brand new. They had all of the features of a police car, such as the lights near the wind shield, bars for crashing at the front, antennae, but no markings anywhere, just black paint. The drivers also looked like police.

Do these kinds of cars perform a special role? They seem useless as undercover vehicles.

Since they aren't marked, do I need to still follow their instructions, such as pulling over?

While traveling in the Southwest, I saw on two different occasions police cars that were painted all black, with no writing or logos on them. One was an older style of a police car, the other was a muscle car that looked brand new. They had all of the features of a police car, such as the lights near the windshield, bars for crashing at the front, antennae, but no markings anywhere, just black paint. The drivers also looked like the police.

Do these kinds of cars perform a special role? They seem useless as undercover vehicles.

Since they aren't marked, do I need to still follow their instructions, such as pulling over?