Can police vehicles record speed of oncoming traffic whilst the police vehicle in motion?
Yes, radar guns can record the speed of oncoming traffic, even when the squad car is moving. It usually accomplishes this task by also recording the speed of stationary objects that are also within the field of the radar which tells the radar gun the speed of the squad car. Example: The radar gun gets stationary objects approaching the squad car at 40mph. This tells the gun that the squad car is going 40mph. It also records the vehicle approaching the squad at 100mph. It does an immediate calculation (subtracting the speed of the squad car from the recorded speed of the oncoming car) and reports that the oncoming car is going 60mph. However, these guns do not take pictures of that vehicle. The officer must execute a traffic stop to issue the citation. The exception to this would be speed limit cameras which operate much like red-light cameras. These devices will record your speed and take pictures of your vehicle for possible issuance of a citation at a later date.
