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.On Monday, February 23, 2009, New York City announced testing camera enforcement of bus lanes on 34th Street in Midtown Manhattan where a New York City taxi illegally using the bus lanes would face a fine of 0 adjudicated by the New York City Taxi and Limousine Commission.In California, that need to identify the actual violator has led to the creation of a unique investigatory tool, the fake "ticket".
In the UK an 80-year-old pensioner John Catt and his daughter Linda were stopped by City of London Police while driving in London, UK in 2005.
They had their vehicle searched under section 44 of the Terrorism Act 2000 and were threatened with arrest if they refused to answer questions.
However, acknowledging receipt of such ticket makes it valid and thus enforceable.
as being in contradiction to the Human Rights Act 1998 on the grounds that it amounted to a 'compulsory confession', also that since the camera partnerships included the police, local authorities, Magistrates Courts Service (MCS) and Crown Prosecution Service (CPS) which had a financial interest in the fine revenue that they would not get a fair trial.
Some groups, such as the National Motorists Association in the USA, claim that systems "encourage ...
revenue-driven enforcement" rather than the declared objectives.
These cameras time vehicles over a known fixed distance, and then calculate the vehicle's average speed for the journey.
In 2007, the Mountains Recreation and Conservation Authority (MRCA), in California, installed the first stop sign cameras in the United States.
Cameras can be concealed, for example in garbage bins.
Mobile speed cameras may be hand-held, tripod mounted, or vehicle-mounted.
In vehicle-mounted systems, detection equipment and cameras can be mounted to the vehicle itself, or simply tripod mounted inside the vehicle and deployed out a window or door.