Why do some police cars not have lights on top?
Why do some police cars not have lights on top? The aerodynamic properties of light bars can be important for police applications, as fuel efficiency and drag are concerns in patrol and pursuit. Because of this, some police cars do not have roof mounted lightbars.
Are cops allowed to hide with their lights off?
They can legally hide with their lights off. And they can pull you over for violating the law, whether they advertised their presence or not. It is not considered entrapment in a court of law.