I apologize if this idea has been mentioned already, but I am trying to catchi up here. How about a code word? The driver and passenger could be assigned a code word or a code number. We teach our kids code words for emergency situations, how about for something like this. That way, no confusion with colors, etc. The code word/number would have to match with display and phone.As opposed to doing nothing, I don't think it's a bad idea. However, I haven't read the proposed legislation. Have you? MOO