Speed cameras

A traffic enforcement camera (also red light camera, road safety camera, road rule camera, photo radar, photo enforcement, speed camera, Gatso, safety camera, bus lane camera, flash for cash, Safe-T-Cam, depending on use) is a camera which may be mounted beside or over a road or installed in an enforcement vehicle to detect traffic regulation violations, including speeding, vehicles going through a red traffic light, unauthorized use of a bus lane, or for recording vehicles inside a congestion charge area. It may be linked to an automated ticketing system.

The latest automatic number plate recognition systems can be used for the detection of average speeds and raise concerns over loss of privacy and the potential for governments to establish mass surveillance of vehicle movements and therefore by association also the movement of the vehicle's owner. Vehicles owners are often required by law to identify the driver of the vehicle and a case was taken to the European Court of Human Rights which found that human rights were not being breached. Some groups, such as the National Motorists Association in the USA, claim that systems "encourage ... revenue-driven enforcement" rather than the declared objectives.

Some bus lane enforcement cameras use a sensor in the road, which triggers a number plate recognition camera which compares the vehicle registration plate with a list of approved vehicles and records images of other vehicles. Other systems use a camera mounted on the bus, for example in London where they monitor Red routes on which stopping is not allowed for any purpose (other than taxis and disabled parking permit holders).

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