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Many jurisdictions operate [[traffic violations reciprocity]] where non-resident drivers are treated like residents when they are stopped for a traffic offense that occurs in another jurisdiction. They also ensure that penalties such as [[Point system (driving)|demerit points]] and the ensuing increase in insurance premiums follow the driver home. The general principle of such interstate, inter-provincial, and/or international compacts is to guarantee the rule 'one license, one record.'{{Cite quote|date=April 2010}}
Many jurisdictions operate [[traffic violations reciprocity]] where non-resident drivers are treated like residents when they are stopped for a traffic offense that occurs in another jurisdiction. They also ensure that penalties such as [[Point system (driving)|demerit points]] and the ensuing increase in insurance premiums follow the driver home. The general principle of such interstate, inter-provincial, and/or international compacts is to guarantee the rule 'one license, one record.'{{Cite quote|date=April 2010}}


Some groups, such as the [[National Motorists Association]] in the USA, claim that systems are used primarily as a source of revenue rather than to enforce traffic rules for the declared objectives. However, studies have demonstrated that speed cameras have been effective in reducing the number of traffic injuries and deaths.<ref>Wilson C, Willis C, Hendrikz JK, Le Brocque R, Bellamy N. Speed cameras for the prevention of road traffic injuries and deaths. Cochrane Database of Systematic Reviews 2010, Issue 11. Art. No.: CD004607. DOI: 10.1002/14651858.CD004607.pub4 http://onlinelibrary.wiley.com/o/cochrane/clsysrev/articles/CD004607/frame.html</ref>
Some groups, such as the [[National Motorists Association]] in the USA, claim that systems are used primarily as a source of revenue rather than to enforce traffic rules for the declared objectives. However, studies have demonstrated that speed cameras have been effective in reducing the number of traffic injuries and deaths.<ref>{{cite journal |author= Wilson C, Willis C, Hendrikz JK, Le Brocque R, Bellamy N |title= Speed cameras for the prevention of road traffic injuries and deaths |journal=Cochrane Database of Systematic Reviews |volume=2010 |issue=11 |pages= CD004607 |year=2010 |pmid= 20927736 |doi=10.1002/14651858.CD004607.pub4 |url=http://onlinelibrary.wiley.com/o/cochrane/clsysrev/articles/CD004607/frame.html}}</ref>


==History==
==History==

Revision as of 14:30, 30 November 2010

Gatso speed camera

Speed limit enforcement is the action taken by appropriately empowered authorities to check that road vehicles are complying with the speed limit in force on roads and highways. Methods used include roadside speed traps set up and operated by the police and automated roadside 'speed camera' systems which may incorporate the use of an automatic number plate recognition system. Traditionally the police would have used stopwatches to measure the time taken for a vehicle to cover a known distance, but latterly they have speed guns and automated in-vehicle systems at their disposal.

Many jurisdictions operate traffic violations reciprocity where non-resident drivers are treated like residents when they are stopped for a traffic offense that occurs in another jurisdiction. They also ensure that penalties such as demerit points and the ensuing increase in insurance premiums follow the driver home. The general principle of such interstate, inter-provincial, and/or international compacts is to guarantee the rule 'one license, one record.'[This quote needs a citation]

Some groups, such as the National Motorists Association in the USA, claim that systems are used primarily as a source of revenue rather than to enforce traffic rules for the declared objectives. However, studies have demonstrated that speed cameras have been effective in reducing the number of traffic injuries and deaths.[1]

History

Traffic calming was built into the UK 1865 'Locomotive Act', which set a speed limit of 2 miles per hour (3.2 km/h) in towns and 4 miles per hour (6.4 km/h) out of town, by requiring a man with a red flag to walk 60 yards (55 m) ahead of qualifying powered vehicles. The distance ahead of the pedestrian crew member was reduced to 20 yards (18 m) in 1878 and the vehicles were required to stop on the sight of a horse.[2] The speed limit being effectively redundant as vehicle speeds could not exceed the speed at which a person could walk.

By 1895 some drivers of early lightweight steam-powered autocars assumed that these would be legally classed as a horseless "carriage" and would therefore be exempt from the need for a preceding pedestrian. A test case was brought by motoring pioneer John Henry Knight who was subsequently convicted with using a locomotive without a licence.[3]

In 1905 The Automobile Association was formed to help motorists avoid police speed traps.[4]

A Royal Commission on 'Motorcars' in the UK reported in 1907 raised concern about the manner in which speed traps were being used to raise revenue in rural areas rather than being used to protect lives in towns. In parliamentary debates at the time it was observed that "Policemen are not stationed in the villages where there are people about who might be in danger, but are hidden in hedges or ditches by the side of the most open roads in the country", "In my opinion they are manifestly absurd as a protection to the public, and they are used in many counties merely as a means of extracting money from the passing traveller in a way which reminds one of the highwaymen of the Middle Ages".[5][6]

In 1910 in legal test case ('Betts -v- Stevens') between Automobile Association patrolman and a potentially speeding motorist and the Chief Justice, Lord Alverston, the judge ruled that where a patrolman signals to a speeding driver to slow down and thereby avoid a speed-trap, that person would have committed the offence of 'obstructing an officer in the course of his duty' under the Prevention of Crimes Amendment Act 1885.[7][8] Subsequently the organisation developed a coded warning system which was used until the 1960s whereby a patrolman would always salute the driver of a passing car which showed a visible AA Badge unless there was a speed trap nearby on the understanding that their officers could not be prosecuted for failing to salute.[9]

Gatsometer BV, founded in 1958 by rally driver Maurice Gatsonides, produced the 'Gatsometer' which was described as "a revolutionary speed-measuring device".[10] Developed initially for improving his race times,[citation needed] it was later marketed as police speed enforcement tool.[10] Gatsometer claim to have developed the first radar for use with road traffic in 1971, but this claim is undermined by evidence that radar detectors were already for sale in 1967.[10] Gatsometer BV produced the world's first mobile speed traffic camera in 1982.[10][11]

VASCAR was is use in North Carolina, New York and Indiana by February 1968.[12]

Methods

Police officers in Bavaria checking speed with a tripod-mounted LIDAR device.

Speed limits were originally enforced by manually timing or "clocking" vehicles travelling through "speed traps" defined between two fixed landmarks along a roadway that were a known distance apart; the vehicle's average speed was then determined by dividing the distance travelled by the time taken to travel it. Setting up a speed trap that could provide legally satisfactory evidence was usually time consuming and error prone, as it relied on its human operators.

Average speed measurement

See also: Automatic number plate recognition

VASCAR is a device that semi-automates the timing and average speed calculation of the original manually-operated "speed trap". An observer on the ground, in a vehicle or in the air simply presses a button as a vehicle passes two landmarks that are a known distance apart, typically several hundred metres.

Automatic number plate recognition (ANPR) systems that use a form of optical character recognition to read the vehicle's licence or registration plate. A computer system reads vehicle registration plates at two or more fixed points along a road, usually hundreds of meters or even kilometers apart, then uses the known distance between them to calculate a vehicle's average speed. If the average speed exceeds the speed limit, then a penalty is automatically issued.[13]).

Police in some countries like France have been known to prosecute drivers for speeding, using an average speed calculated from timestamps on toll road tickets.[14]

Instantaneous speed measurement

Texas police officer using a LIDAR speed gun

Instantaneous speed cameras measure the speed at a single point. These may either be a semi-permanent fixture or be established on a temporary basis. A variety of technologies can be used:

Pacing

Officers in some jurisdictions may also use pacing, particularly where a more convenient radar speed measuring device is not available—a police vehicle's speed is matched to that of a target vehicle, and the calibrated speedometer of the patrol car used to infer the other vehicle's speed.[17]

Other

Some jurisdictions such as Australia, allow prosecutions based on a subjective speed assessment by a police officer.[18]

Evidence gathering

UK fixed speed camera, showing "Dragon's Teeth" painted on the road"

While digital cameras can be used as the primary means of speed detection when combined with automatic number plate recognition (ANPR) average-speed camera systems, their use is more commonly restricted to evidence gathering where speeding offences are detected by various other types of sensors such as such as Doppler radar, piezo strips, infrared or laser devices.[citation needed]

Photographs are typically time-stamped by a high resolution timing device so that a vehicle's speed can be checked manually after the fact if necessary using the secondary method of calculating its speed between a series of calibrated lines (known as "Dragon's Teeth") painted on the road surface.[19]

The change from analogue "wet film" to digital technology has revolutionised speed cameras, particularly their maintenance and the back-office processing required to issue penalty notices. Images from digital cameras can be uploaded in seconds to a remote office over a network link, while optical character recognition software can automate the "reading" of vehicle registration numbers.[20]

Types of camera include Gatso, Truvelo Combi and D-cam.

Avoidance and evasion

Passive RADAR and LIDAR detector

Some drivers use passive radar detectors or LIDAR detectors to detect police radar or LIDAR signals, with the intention of avoiding or evading prosecution by slowing down before entering an enforcement zone. The legal standing of these type of devices varies by jurisdiction.[21] Active devices might also be used—in this instance radar or LIDAR signals are typically jammed with counter emissions. These devices are more frequently illegal than passive devices.

Drivers may flash their lights to approaching drivers to warn them of a speed trap. The legal standing of this action also varies by jurisdiction.[22]

In 2006 the UK Automobile Association controversially published a road map that included the location for thousands of speed cameras—the first time such information was available in printed form,[23] although more accurate and frequently-updated GPS-based information was freely available for some time before that.

Tolerances

Speed limits may not be enforced for speeds close to the legal limit. In the United States, speeding enforcement tolerance is usually up to the discretion of the arresting officer. Some states (such as Pennsylvania) have official tolerances.[citation needed] In the United Kingdom ACPO guidelines recommend a tolerance level of the speed limit "+10% +2 mph" (e.g., a maximum tolerance in a 30 mph (50 km/h) zone of 30 + (30 × 10% = 3) + 2 = 35 mph).[24]

In Germany, a 3 km/h tolerance (4 km/h when speeding over 100 km/h) in favor of the offender is always deducted. Fines for speeding depend on how high above the speed limit the measured speed is and where the offense occurred. Speeding in built-up areas invariably carries higher fines than outside city limits. While fines for minor offenses tend to be moderate, speeds in excess of 20 km/h (12 mph) above the limit in built-up areas and 30 km/h (19 mph) on other roads result in distinctly higher fines and points on the driver's license, and, depending on the speed at which the offender was clocked, may lead to a driving ban of at least one month.[citation needed]

The state of Victoria in Australia allows for only a 3 kilometres per hour (1.9 mph) tolerance on the basis that although the increased risk is lower there are very many more drivers involved which creates a substantial risk across the road network.[25] An alternate view is that police devices are accurate to 1 km/h, and that a 2–3 km/h tolerance is the minimum margin that police require to defeat any challenge in court regarding the accuracy of their speed measurement equipment.[26]

Speed limit policy can affect enforcement. According to a 1994 report by the AASHTO, "experience has ... shown that speed limits set arbitrarily below the reasonable and prudent speed perceived by the public are difficult to enforce, produce noncompliance, encourage disrespect for the law, create unnecessary antagonism toward law enforcement officers, and divert traffic to lesser routes".[27]

In Mexico City, maximum speed limit on freeways and beltways is set as 80 kilometres per hour (50 mph). However, fines are only given when speeding above 90 kilometres per hour (56 mph), thus giving a 10 kilometres per hour (6.2 mph) tolerance. Speed limit is enforced by an automatically-set camera. The device takes a picture of the speeding car's license plate and sends a printed fine by mail directly to the driver's home.
Mexican highway patrol may enforce speed laws only when a car is speeding above reasonable speeds in regard of the amount of traffic. Maximum speed for all Mexican highways is 110 kilometres per hour (68 mph). Speeding fines are given to those going 130 kilometres per hour (81 mph) and up to 220 kilometres per hour (140 mph). Police may however place a Dodge Charger vehicle as a pace car so drivers behind cannot overpass 100 kilometres per hour (62 mph); this is common during Summer and Winter holiday season.

Law enforcement approaches

Local conditions, law and police practices mean that the tactics adopted to catch speeding motorists vary considerably. In some regions, police may adopt a more subtle approach, concealing themselves and their equipment as much as possible; other jurisdictions require highly visible policing, with cameras painted yellow, and camera operators not permitted to use approaches such as attaching the camera to what may appear to be a broken-down vehicle when enforcing speed limits.

Authorities are not able to monitor every vehicle on every road—limited resources generally mean that enforcement needs to be targeted. A New Zealand study concluded that actual enforcement as well as the perceived chance of being caught both contributed to changes in drivers' behaviour.[28]

Extra-judicial enforcement

In 2001, Acme-Rent-a-Car in Connecticut controversially tried to use a contractual clause in the rental agreement to issue speeding fines to any of its customers that exceeded speed limits as detected by GPS tracking units its cars. The company actions were challenged and defeated in court.[29][30]

Regional issues

Australia

See also: Speed limits in Australia
Gatso Mobile Speed Camera, used in Victoria, Australia. The camera is mounted on the passenger side dash, whilst the black box on the front is the radar unit.

In 2004 a government inquiry in the state of Victoria found that maintenance and accuracy checks had not been done on a regular basis. This had resulted in a 4-cylinder Datsun 120Y sedan reported as doing 158 km/h, while the maximum speed it was capable of was found to be only 117 km/h.[31]

In August 2005, in Sydney, Australia a speed camera photograph was challenged on the basis that an MD5 cryptographic hash function used to protect the digital photograph from tampering was not robust enough to guarantee that it had not been altered. Magistrate Lawrence Lawson demanded that the Roads and Traffic Authority (RTA) produce an expert witness who could prove the photographs were tamper-proof, but the RTA was unable to provide such evidence. The defendant was acquitted and awarded court costs.[32]

Victoria achieved record low road tolls in both 2008 and 2009.[33][34] A report about the 2009 road toll reduction credited increased use of mobile speed cameras to police speed limits as having contributed to the result for that year.[34]

Canada

Speed limit enforcement cameras were a substantial election issue in the province of Ontario, Canada and were abolished by the premier Mike Harris in 1995.

In February 2006, Edmonton, Alberta, Canada erupted in scandal when it was alleged that two police officers accepted bribes from private contractors who received lucrative contracts to provide speed limit enforcement cameras. The officers and contractor involved now face criminal charges that remain before the courts.[35]

United Kingdom

Main article: Road speed limit enforcement in the United Kingdom

The United Kingdom uses a variety of methods to enforce its road speed limits including average and instantaneous speed cameras, however eight counties are to switch off or remove cameras and a further two counties are considering such action.[36][37][38][39][40]

There has also been debate as to whether the use of such cameras in order to force a driver to confess to the crime of speeding is in violation of European basic human rights; however, in 2007 the European Court of Human Rights, in O’Halloran and Francis v United Kingdom, found there was no breach of article 6 of the Human Rights Act 1998 in requiring the keepers of cars caught speeding on camera to provide the name of the driver, or to be subject to criminal penalty of an equivalent degree of severity if they failed to do so.[41]

The number of designated traffic officers fell from 15–20% of Police force strength in 1966 to seven per cent of force strength in 1998, and between 1999 and 2004 by 21%[42]. It is an item of debate whether the reduction in traffic accidents per 100 million miles driven over this time[43] has been due to robotic enforcement.

United States

See also: Speed limits in the United States

In the U.S. state of Ohio, the issue of whether a city has jurisdiction under the Ohio Constitution to issue citations based on speed cameras will be heard by the Ohio Supreme Court on September 18, 2007, in the case of Kelly Mendenhall et al. v. The City of Akron et al.[44][45]

They are illegal in Nassau County, Yonkers, Buffalo, Rochester, and Suffolk County,[46][dead link] except in toll lanes equipped with E-ZPass where driving through at a speed in excess of the posted limit can result in a Speed Notice indication.[47]

Some U.S. states that formerly allowed red-light enforcement cameras but not speed limit enforcement cameras ('photo radar'), have now approved, or are considering, the implementation of speed limit enforcement cameras. The Maryland legislature approved such a program in January 2006. In 2005, 2006, 2008 and 2009 the California legislature considered, but did not pass, bills to implement speed limit enforcement cameras.[48] Tennessee legislators are also considering expanding their speed limit enforcement cameras after successes in Chattanooga such as generating $158,811 in revenue in the first three months.[49][50]

A 2007 study of speed cameras on the Arizona State Route 101 in Scottsdale found a 50% reduction in the total crash frequency, with injuries falling by 40% however rear-end collisions increased by 55%.[51]

As of late 2008 cameras are being placed along all Phoenix area freeways capturing drivers doing speeds greater than 11 mph over the posted speed limit. Over 100 new cameras are expected to be up and running by 2009.[52]

As of 2009 speed cameras existed in 48 communities in the United States, including in Arizona, Colorado, Illinois, Iowa, Louisiana, Maryland, Massachusetts, New Mexico, Ohio, Oregon, Tennessee, Washington, and Washington, DC.[clarification needed][53]

In the United States, it is common for all installation, operation, and verification procedures to be carried out by private companies that in some States receive payment based on the number of infringements they issue, and often under no testing regime whatsoever,[54] however these units are required by law to take at least two pictures of each vehicle.[55]

Opposition groups have formed in some locations where automated traffic enforcement has been used. In the US city of Scottsdale Arizona, an activist group CameraFraud was formed and staged sign-wave protests and petition drives to oppose the use of speed limit enforcement cameras ('photo radar').[56][57][58] In the 2008 elections in nearby Pinal County, Paul Babeau won an election for Sheriff after making a campaign promise to eliminate speed cameras.[59]

It has been announced that Arizona will not renew its contract with Redflex, the company that operates the cameras.[60]

See also

References

  1. ^ Wilson C, Willis C, Hendrikz JK, Le Brocque R, Bellamy N (2010). "Speed cameras for the prevention of road traffic injuries and deaths". Cochrane Database of Systematic Reviews. 2010 (11): CD004607. doi:10.1002/14651858.CD004607.pub4. PMID 20927736.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ "MVRUS - Legislation: A summary of important legislation". UK Department of the Environment.
  3. ^ Wey River "History of Farnham". Retrieved 2010-04-26. {{cite web}}: Check |url= value (help)
  4. ^ "About us". The AA. Retrieved 2010-02-26.
  5. ^ "Debate on the Royal Commission on Motor Cars". Hansard. 24-05-1906. Retrieved 2010-04-17. {{cite web}}: Check date values in: |date= (help)
  6. ^ "MOTOR CAR LEGISLATION". Hansard. 16-07-1907. Retrieved 2010-04-17. I regard the abolition of the speed limit as the most important recommendation of the Royal Commission... Policemen are not stationed in the villages where there are people about who might be in danger, but are hidden in hedges or ditches by the side of the most open roads in the country... I am entirely in sympathy with what the noble Earl said with regard to police traps. In my opinion they are manifestly absurd as a protection to the public, and they are used in many counties merely as a means of extracting money from the passing traveller in a way which reminds one of the highwaymen of the Middle Ages. {{cite web}}: Check date values in: |date= (help)
  7. ^ JA Coutts, 'Obstructing the Police' (1956) 19 MLR 411
  8. ^ "Road Traffic - 1900- 1929". swarb.co.uk. Retrieved 2010-02-27.
  9. ^ Massey, Ray (2010-02-04). "Drivers face breakdown nightmare after AA staff ballot for first strike in 105 years". The Daily Mail. London.
  10. ^ a b c d "History". Gatsometer. Retrieved 2010-04-18.
  11. ^ "Radar Speed Trap Warning Apparatus (Licence)". Hansard. 1967-03-02. Retrieved 2010-04-25. a pocket-sized instrument is being produced by Marchant House Limited of New Street, Oadby, Liecester, to be used in motor vehicles to give instant warning of a police radar speed trap ... Anyone wishing to use this type of apparatus would require a licence under the Wireless Telegraphy Act, 1949. The firm in question has recently been informed that I am not prepared to issue a licence for such purposes
  12. ^ "The Highway: Versatile VASCAR". Time. February 9, 1968.
  13. ^ "Specs spies on speeding motorists". BBC News. July 14, 2005. Retrieved 2008-05-31.
  14. ^ Brian Bell (2001). Insight Guide: French Riviera. Langenscheidt Publishers. p. 318. ISBN 158573148X.
  15. ^ US 5521696 
  16. ^ "Police Speed Enforcement Cameras". Safer motoring. Retrieved 2010-04-19.
  17. ^ Police Technology. 2004. Pearson Prentice Hall: 15. 2004. ISBN 0131149571 http://books.google.com/books?lr. {{cite journal}}: Missing or empty |title= (help)
  18. ^ Alan Buckingham (2003-10-17). "Speed Traps: Saving Lives or Raising Revenue?". Retrieved 2010-04-27. [dead link]
  19. ^ "Gatso Photo Checking". Association of British Drivers. Retrieved 2010-04-26.
  20. ^ Max Cameron (2008-06-10). Development of Strategies for Best Practice in Speed Enforcement in Western Australia (PDF) (Report). Monash University Accident Research Centre. p. 6.
  21. ^ "Radar detectors FAQ". Whistler Group. Retrieved 2010-09-17.
  22. ^ "Driver upset after ticketed for flashing headlights". CFTO-TV. 30 January 2008. Retrieved 2009-09-17. A Toronto man is upset he was ticketed for flashing his headlights to tip off oncoming drivers of a radar speed trap, especially since police admit the act is not illegal.'
  23. ^ Bloomfield, Steve (2005-06-26). "AA causes fury by publishing its first-ever map of speed cameras". The Independent. London. Retrieved 2010-04-17. A controversial decision by the AA to publish its first map of speed traps has provoked a storm of protest from safety experts, who accuse the organisation of encouraging motorists to break the law.
  24. ^ http://www.safespeed.org.uk/speeding.html
  25. ^ "Making travel safer: Victoria's speed enforcement program". Victorian Auditor General. 20 July 2006. Retrieved 2009-10-18. {{cite journal}}: Cite journal requires |journal= (help) [dead link]
  26. ^ S.P. Hardy. "Inaccurate Speedos". trafficlaw.com.au. Retrieved 2010-04-28.
  27. ^ "AASHTO Policy Resolution: The National Statutory Speed Limit". American Association of State Transport Highway Officials. 19 April 1994. Retrieved 2009-09-17.
  28. ^ Organisation for Economic Co-operation and Development, European Conference of Ministers of Transport, OECD/ECMT Transport Research Centre (2006). Speed Management. OECD Publishing. p. 155. ISBN 9282103773.{{cite book}}: CS1 maint: multiple names: authors list (link)
  29. ^ Robert Lemos (2001-07-02). "State Puts Brakes on GPS Speeding Fines". CNET. Retrieved 2010-04-29.
  30. ^ Amy D. Propen (2006-06-10). "Critical GPS: Toward a New Politics of Location" (PDF). Department of Rhetoric, University of Minnesota. {{cite journal}}: Cite journal requires |journal= (help)
  31. ^ http://www.abc.net.au/7.30/content/2004/s1121730.htm
  32. ^ "NSW Speed Cameras in Doubt". Melbourne: The Age. 2005-08-10. Retrieved 2010-04-28.
  33. ^ Dowling, Jason (2009-01-01). "State's road toll dips to its lowest on record". Melbourne: The Age.
  34. ^ a b Sexton, Reid (2009-12-27). "Victoria's road toll at record low". Melbourne: The Age.
  35. ^ [1]
  36. ^ "Lack of police funds could end South West speed cameras". BBC News. 2010-07-22.
  37. ^ http://www.thisisgloucestershire.co.uk/news/Speed-cameras-stay-maintenance/article-2481320-detail/article.html
  38. ^ http://www.mirror.co.uk/news/top-stories/2010/08/02/speed-camera-turn-off-starts-115875-22457737/
  39. ^ "Town ditches fixed speed cameras". BBC News. 2009-07-31.
  40. ^ Barrett, David (2010-08-07). "Speed camera switch-off sees fewer accidents". The Daily Telegraph. London.
  41. ^ "O'Halloran and Francis v. The United Kingdom".
  42. ^ Section 21, traffic officer numbers reduction in the UK
  43. ^ page 147 Transport statistics 2009 edition
  44. ^ [2]
  45. ^ [3]
  46. ^ Several Sections numbered 1111-b (Owner liability for failure of operator to comply with traffic-control indications) of the Vehicle and Traffic Law permits red light cameras in these five jurisdictions. They will expire on December 1, 2014 if not renewed then.
  47. ^ E-ZPass FAQ, E-ZPass New York Service Center
  48. ^ [4]
  49. ^ [5]
  50. ^ "City Red Light, Speeding Cameras Bring In $158,811 In First 3 Months". The Chattanoogan.com. 2007-11-14. Retrieved 2008-09-01.
  51. ^ study of speed cameras
  52. ^ [6][7]
  53. ^ "Speed cameras on U.S. highways?". CNN. June 4, 2009. Retrieved 2009-06-05. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  54. ^ San Diego Court Ruling, 2001.
  55. ^ US Department Of Transportation Federal Highway Administration - Traffic Enforcement Camera Regulations, December 9 th 2008.
  56. ^ http://www.myfoxphoenix.com/myfox/pages/Home/Detail;jsessionid=DE43213CB3C503CF8E9DC6239DACB7D0?contentId=7996744&version=2&locale=EN-US&layoutCode=VSTY&pageId=1.1.1&sflg=1
  57. ^ http://www.azfamily.com/video/localnews-index.html?nvid=322272&shu=1
  58. ^ http://www.abc15.com/content/news/phoenixmetro/story/Valley-activists-working-to-protest-photo-radar/CfKdulyJ0EGDqa7OXX2BuA.cspx
  59. ^ http://www.myfoxphoenix.com/myfox/pages/Home/Detail?contentId=8188969&version=1&locale=EN-US&layoutCode=VSTY&pageId=1.1.1
  60. ^ http://ktar.com/?nid=6&sid=1291566

External links

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