Re: the previous posts - ANPR
You might want to have a read of this then.
"How it works
As a vehicle passes an ANPR camera, its registration number is read and instantly checked against database records of vehicles of interest. Police officers can intercept and stop a vehicle, check it for evidence and, where necessary, make arrests. A record for all vehicles passing by a camera is stored, including those for vehicles that are not known to be of interest at the time of the read that may in appropriate circumstances be accessed for investigative purposes. The use of ANPR in this way has proved to be important in the detection of many offences, including locating stolen vehicles, tackling uninsured vehicle use and solving cases of terrorism, major and organised crime. It also allows officers’ attention to be drawn to offending vehicles whilst allowing law abiding drivers to go about their business unhindered."