mostly in either UN marked crown Victoria, but everyone knows that so i am also confident that they may use personal vehicles from home, it is less noticeable. police need an affidavit or warrant to tap your phone lines so i don't think its worth worrying about. if anyone unusual is walking around your street or nearby your home its a undercover. most undercover police use their drug task force sting operation assets because they blend in with all the people in the city. i took criminal justice for a year so i know allot. also be aware that most if not all cops bend the law for their favor assuming that citizens don't know law. so they can get away with it.