Quote:Fair enough. To answer your question, if an undercover officer reasonably believes that the person driving that vehicle is intoxicated or otherwise impaired, or presents a clear and present danger to others on the road (i.e., weaving around other cars at 10-15+ over the speed of traffic), that officer should respond to it as they would any other life-threatening situation whether their car is marked or not, but they should immediately inform dispatch of what they're doing and request marked backup asap.

 

What unmarked cars should not be doing is conducting traffic enforcement, or even simple traffic stops for things like speeding, crossing a double-yellow or, as the assailant in the OP was accused of, the general umbrella of "driving erratically". They should not be pulling up to people's houses to question the occupants without marked accompaniment. That's what marked units are there for. They exist to provide a visible police presence, and any situation that could easily lend itself to an impostor bringing harm to an innocent person is not one that should be handled by a cop in plain clothes and an unmarked car--i.e., a cop that has a relatively high likelihood of being a criminal in disguise.