When I report a police vehicle, the map drops a pin where I reported the incident. With the traffic feature, it gives me options: moderate, heavy, and stand still. Sometimes the police vehicle I am reporting is: (1) moving in traffic with me, (2) seen going the opposite direction, (3) seated in a parked location, or (4) just seen in the area. If the pin just drops and stays and the police vehicle is moving with me, it is no longer accurate within seconds. If the police vehicle is going in the opposite direction, that is also true. If you give a sub-option to report an additional detail on the police vehicle, it can maybe place it in motion on the map, thus alerting other wise members that the vehicle is, for instance, southbound on the freeway, etc. Or heading in your direction. I think this detail gives more important information as to direction of travel and the like to alert those around of incoming our outgoing police vehicle traffic. Or if it was just seen in the area.