I'll just call you, okay?display of forward facing red/blue lights in a non-police vehicle is not legal.
Per state law, to enforce traffic law a LEO must EITHER be in a fully marked police vehicle OR in full agency uniform. If someone you believe to be a poser lights you up, call 911 and ask for the real cops. If you decide to talk to the supposed poser, ask for ID and for a supervisor. Real cops will have ID and must call for a supervisor if you request one. If you are in fear of your life/safety from the poser (fear other than the fact that they are a poser) GTFO and proceed to a public, well-lit area or police/fire station.