A red light camera (short for red light running camera [1]) is a type of traffic enforcement camera that photographs a vehicle that has entered an intersection after the traffic signal controlling the intersection has turned red.[2] By automatically photographing vehicles that run red lights, the photo is evidence that assists authorities in their enforcement of traffic laws.[3][4] Generally the camera is triggered when a vehicle enters the intersection (passes the stop-bar) after the traffic signal has turned red.
Typically, a law enforcement official will review the photographic evidence and determine whether a violation occurred. A citation is then usually mailed to the owner of the vehicle found to be in violation of the law.[5] These cameras are used worldwide, in China, in European countries, and in countries including: Australia, New Zealand, Canada, Indonesia, the United Kingdom, Singapore and the United States.[6][7] More than 75 countries worldwide use red light cameras.[8]
If a proper identification of the driver cannot be made, instead of a ticket, some jurisdictions send out a notice of violation to the owner of the vehicle, requesting identifying information so that a ticket may be issued later. Other jurisdictions simply assess a fine to the owner of the vehicle and make no attempt to determine personal responsibility for the offence beyond that; in such locales owners are responsible for collecting the fine from the offending driver (assuming it is not themselves); however, such jurisdictions generally do not assign demerit points or other personal consequences for traffic offences caught on camera.
According to the Insurance Institute for Highway Safety, red-light running is a frequent cause of crashes, with 6,000 people killed between 1992 and 1998, 850 each year in the United States alone, while 1.4 million were injured. In Australia, 15% to 21% of the crashes at signalized intersections were related to red light running during 1994–1998.[9]
There is debate and ongoing research about the use of red light cameras. Authorities cite public safety as the primary reason that the cameras are installed,[10][11][12] while opponents contend their use is more for financial gain.[13][14] There have been concerns that red light cameras scare drivers (who want to avoid a ticket) into more sudden stops,[15][16] which may increase the risk of rear-end collisions. The elevated incentive to stop may mitigate side collisions. Some traffic signals have an all red duration, allowing a grace period of a few seconds before the cross-direction turns green. Some studies have confirmed more rear-end collisions where red light cameras have been used, while side collisions decreased, but the overall collision rate has been mixed. A systematic review summarized evidence from 38 studies and found that overall, red-light cameras are effective at reducing right angle crashes and related injuries, as well as total injuries, but they also lead to an increase in rear end crashes.[17] In some areas, the length of the yellow phase has been increased to provide a longer warning to accompany the red-light-running-camera. There is also concern that the international standard formula used for setting the length of the yellow phase ignores the laws of physics, which may cause drivers to inadvertently run the red phase.[18]
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was invoked but never defined (see the help page).SanDiego
was invoked but never defined (see the help page).An additional issue is that many red light cameras use compressed video, making it impossible for the ticket holder to prove they were within the "dilemma zone". A dilemma zone is the area where a driver finds it is impossible to either stop in time or proceed through the intersection before the light turns red.