Select Committee on Transport Tenth Report

6  Speed enforcement

106. The use of camera technology to enforce speed limits illustrates how the technology of enforcement cannot be treated in isolation from political and social factors.[163] The decisions taken in relation to safety cameras and the national guidelines set down to govern their use have been based on considerations other than simply the effectiveness of the technology in enforcing limits and reducing road deaths and injuries.

Safety Camera Partnerships

107. Speed cameras were first used on the UK's roads in 1992.[164] The use of cameras has radically increased the detection of speed limit violations. Between 1999 and 2002 the number of speed offences detected by speed cameras increased from about 500,000 to 1,400,000.[165] Their effect in reducing speeding can be seen in the fall in the percentage of drivers breaking the speed limit. In 1994, 69% of drivers exceeded the 30 miles per hour limit; by 2005 this had fallen to 50%.[166]

108. Whilst cameras are clearly effective in reducing speeding and red light running, research indicated that the full benefits of cameras were not being realised because of budgetary constraints. In 1998 the Government decided to allow local road safety partnerships to recover their enforcement costs from penalty charges incurred by offenders. The Partnerships could not make a profit from the operation; any surplus went to the Treasury. The Safety Camera Partnerships were piloted in 2000 in eight areas. The Vehicles (Crime) Act 2001 allowed the system to be extended nationally. Local partnerships consist of the police, local authorities, the Magistrates' courts, the Highways Agency (where appropriate) and other key stakeholders including the local health authority.[167]

Cameras successfully reduce death and injury

109. Evaluation of the safety camera partnerships over the four year period from April 2000 to March 2004 identified their success in reducing speeding and the resultant casualties. The evaluation found that vehicle speeds had been reduced by 70% at new fixed camera sites and by 18% at new mobile sites. Reductions in the proportion of vehicles breaking the speed limit by 15 miles per hour or more were even greater. Both casualties and deaths were down—after allowing for the long-term trend, but without allowing for selection effects (such as regression-to-mean)[168] there was a 22% reduction in personal injury collisions at sites after cameras were introduced.[169] Overall 42% fewer people were killed or seriously injured. After allowing for both regression-to-mean and long-term trends in collision frequencies, the average effect of a sample of 216 cameras was a reduction of 19% in both personal injury collisions and fatal and serious collisions.[170]

110. Despite the impression sometimes given by the media, there is no doubt that speed camera enforcement is very strongly supported by the public. Research found that throughout the last decade, on average 82% of people approved of speed camera operation.[171] There was also a positive cost-benefit ratio of around 1:2.7. In the fourth year, the benefits to society from the avoided injuries were in excess of £258 million compared to enforcement costs of around £96 million. RoadPeace pointed to the efficiency of speed camera enforcement compared to officer enforcement:

A police officer must document every contact with the public and this is estimated by the police to take 15 minutes. We believe this should be publicised and the effectiveness of cameras (which could detect hundreds of speeding incidents in this time) should be compared.[172]

Research by TRL has identified that although cameras are very efficient, physical policing methods can have a different type of impact. The researchers found that the minimum distance halo associated with physical policing is about five times greater than the minimum associated with speed cameras.[173] This reinforces the argument for both officer and technological enforcement, but does not detract from the efficiency of camera enforcement.


111. Although the Safety Camera Partnerships achieved a great deal in the first four years of operation, it was put to us that the impact had been subdued by the guidelines which the Government had adopted. The criteria most criticised were the visibility standards and the requirement for four road deaths or serious injuries to have happened in the previous three years at camera locations.[174] The Slower Speeds Initiative told us:

In reaction to controversy the Government imposed rules for camera visibility and siting criteria that reduced the camera sphere of influence and encouraged drivers to speed outside the range of cameras. Both of these effects could be expected to counteract the casualty reducing potential of the technology […] Speed cameras would be made much more effective if they were inconspicuous and deployed randomly. [175]

The West Yorkshire Road Safety Strategy Group identified that the speed criteria in the guidelines were problematic on rural roads: "In West Yorkshire […] most of the rural roads do not meet the speed criteria, despite meeting the casualty criteria. However these roads often have a significant proportion of drivers who exceed the speed limit by more than 20 mph, whilst the majority obey the limit."[176]

112. The Strategy Group also criticised the requirement for deaths and injuries to have occurred and stated: "The public find it difficult to understand why safety cameras cannot be used when they see many collisions at a location only to be told that they were not serious enough."[177] This was a common complaint. Ms Williams of Brake told us: "If you tell a community that until they have sacrificed their children's lives or injured them they cannot have a camera outside their school or their community, they are not desperately happy about that."[178] Ms Mitchell of the Slower Speeds Initiative pointed out that it is not necessary to wait until collisions and casualties have occurred because the speed/crash relationship is categorical.[179] The frequency of collisions and the severity of casualties increase with speed. Depending on the type of road, every 1 mile per hour reduction in average speed will reduce crashes by between 2-7%.[180]

113. The Department for Transport and Home Office countered that rules governing the National Safety Camera Programme have ensured that cameras have been used only where they meet a proven road safety need.[181] The Departments also argued that the visibility guidelines had won public support: "The decision to adopt a high visibility enforcement approach […] has generally been welcomed by the public and has led to sustained levels of public support for the programme and use of camera technology."[182] The Departments have no hard evidence, however, to support this assertion.[183]

114. Even with these strict guidelines we heard there were many locations which met the criteria, but where cameras had not yet been installed.[184] The Association of Chief Police Officers indicated that between only one and seven per cent of the road network is currently covered by Safety Camera Partnership activity.[185] Transport for London noted that there are potentially 300 sites in London alone which meet the criteria of the National Safety Camera Partnership guidelines and which are not yet covered by safety camera equipment.[186]

115. Despite the success in bringing down the collision and casualty rate the Association of Chief Police Officers, unlike road safety campaigners and local authorities, was not keen for more cameras to be installed. Mr Hughes of ACPO told us: "I do not want to see an extension of the numbers of speed cameras currently in use. I would welcome the flexibility to move those cameras to sites where the killed and seriously injured rate has risen."[187] The Police Federation indicated that cameras should be given less, not more, emphasis: "we believe there is an over reliance now on enforcement cameras, which have fallen under the control of camera partnerships."[188]

116. The Department and the Home Office were reticent when it came to recommending more cameras. The Transport Minister suggested that partnerships should be encouraged to look at solutions to speeding other then cameras. He told us: "it was clear to us that, in certain areas, partnerships had formed which might be minded to look first for a road camera based solution rather than a better and perhaps more cost effective solution."[189]

117. We questioned the Department about which measures were more effective and more cost-effective than speed cameras. The response from the Department identified a comparative study of measures which had been implemented: a speed camera in Bicester; a road hump in Abingdon; a 20 mph zone in Sutton; and a vehicle-activated sign in Norfolk.[190] These examples were taken from the Department's Road Safety Good Practice Guide and set out the reduction in speed and casualties following implementation of the measure and the cost benefit in terms of the first year rate of return. In these examples the 20 mph zone and the speed-activated sign had achieved greater casualty reduction than the camera (8.1 and 3.1 per year respectively, compared to 2.2). In terms of the value for money, however, the speed camera was shown to be the most cost-effective (the first year rate of return was 12 times the cost, compared to 0.8 and 10.6 respectively).

118. It was disappointing that whilst acknowledging the essential role of safety cameras, the Association of Chief Police Officers' Head of Road Policing did not wish to see more cameras in use. We find such a contradictory approach bewildering. Well-placed cameras bring tremendous safety benefits at excellent cost-benefit ratios. A more cost effective measure for reducing speeds and casualties has yet to be introduced. An increase in safety camera coverage would be supported by evidence, as well as public opinion. There are many more sites which meet the existing camera guidelines and more funding should be made available to enable better coverage.

119. The police and road safety campaigners want flexibility on where and how to deploy cameras. It is a disgrace that the existing Department for Transport guidelines require potentially preventable deaths and injuries to have occurred in a location before cameras can be installed. The relationship between speed and collisions is so well proven that this requirement is unnecessary and even irresponsible. Evidence of excessive speed is evidence of danger and there is no need to wait for somebody to die in order to take action intended to slow vehicles. We recommend that the casualty criteria be lifted. Future guidance from the Department should emphasise the importance of local decisions about camera siting: there should be more flexibility for rural roads with casualty problems which do not meet speed criteria and urban roads which cannot fulfil the visibility requirements.

Enforcement threshold speeds

120. We heard that the impact of cameras had also been lessened by the artificially high enforcement threshold speeds.[191] The Slower Speeds Initiative stated: "The threshold speeds which trigger enforcement are well above, and increasingly known to be above, the speed limit."[192] This is a real concern as research by Corbett and Caramlau identified that around 40% of vehicles travel above the 30 miles per hour speed limit but below the prosecution threshold speed.[193] It is at precisely these speeds that a pedestrian's chance of surviving a collision is cut drastically: a pedestrian is more than twice as likely to be killed if hit at 35 miles per hour than at 30 miles per hour.[194] Gloucestershire County Council also noted that the threshold speeds differ in police authority areas across the country, leading to inconsistency.[195]

121. The threshold speeds are set above the actual speed limit to avoid disputes about actual speed travelled. Even driving a few miles per hour over the speed limit makes a big difference in a collision with a pedestrian or cyclist: the chances of survival halve between collisions at 30 miles per hour and 35 miles per hour. With more accurate camera equipment and with accurate digital speedometers installed in vehicles, it would be possible to lower the enforcement threshold speeds. The Government and the police should work towards harmonizing threshold speeds and reducing these to nearer the actual speed limit in order to improve the effectiveness of speed cameras, and to better protect pedestrians and cyclists.


122. The Secretary of State for Transport announced in December 2005 that the current Safety Camera Partnership rules and programme will cease on 31 March 2007.[196] Under the proposed new arrangements, penalty charge revenue from offenders will go to the Treasury and will no longer be ring-fenced for safety camera enforcement operations. The Treasury will then make funding—£110 million in the first year[197]—available to local authorities through the Local Transport Plan system. The funding can be spent on any road safety initiatives and is not therefore restricted to camera operations.

123. The Home Office and the Department for Transport have indicated that the new system is designed to encourage a greater mixture of safety measures. The Home Office Minister told us:

What we are very keen on is to make sure that the money generated is not just spent on more and more cameras but is spent on a more comprehensive approach to road safety. It is very important […] that we get a properly balanced enforcement strategy that reflects the needs of particular local communities [...][198]

The Department for Transport stated:

local partnerships will have much greater local freedom to pursue whichever locally agreed mix of road safety measures will make the greatest contribution to reducing road casualties […] this will also facilitate longer term financial planning and stability. The Government fully expects that camera technology will continue to feature in those local decisions. However local partnerships will also able to direct further resources to more traditional policing methods if this is considered to be a local priority.[199]

124. The greater degree of flexibility was welcomed.[200] The move away from hypothecation was also supported by some witnesses because a widely-held, but mistaken, belief that the cameras were raising net revenue for the Safety Partnerships was thought to be obscuring the real issues.[201] The RAC Foundation stated: "using the revenue for a broader range of education, engineering and enforcement projects [...] would remove any doubt about the priorities, reduce criticism and produce a better […] road safety package."[202] Mr Rob Salmon, of West Sussex County Council, added: "the benefit is the removal of the linkage between expenditure and fine income because that has been perceived nationally as a very negative aspect of the safety camera programme."[203]

125. Nevertheless, there was concern that the new funding arrangements would harm the partnership working that has been developed and in particular that the police would be negatively affected. As the Parliamentary Advisory Council for Transport Safety (PACTS) stated:

PACTS is concerned that as prime responsibility lies with the highways authorities, without a structure bringing together regional road safety stakeholders, the role of the police in determining local road safety interventions may be diminished […] there is thus potential for the role of safety cameras in casualty reduction to also be diminished.[204]

126. All levels of the police service shared this concern. The Association of Chief Police Officers stated: "Whilst forces are generally supportive of the proposed changes, there is some concern that since the funding is not ring-fenced, funding might be diverted away from safety cameras by other partners."[205] The Police Federation told us:

The sweeping changes made to funding arrangements are likely to have a significant impact on the way road safety partnerships function. Local authorities will be able to receive 70 per cent of the funding without any "strings attached". Some may choose to take the money and abandon the safety cameras—possibly handing them back to the police […] this will have clear implications for the way safety cameras are managed.[206]

Mr Barnett, representing the Police Superintendents' Association of England and Wales, added: "The concern we have is that we do not want to be left with the rump of all the enforcement without the support of the funding that comes with it."[207]

127. Transport for London has also expressed concern that the new funding arrangements will limit the plans it has to expand coverage by safety cameras.[208] Under current arrangements, this expansion could have been self-funding, but with the new system Transport for London has been informed it has a fixed budget for camera partnership activities of £10.5 million to £12.5 million for the financial years 2007-08, 2008-09 and 2009-10. The organisation told us: "It is our current understanding that our growth could only be at the expense of another Partnership's decline." An additional concern about the new arrangements was that without the national structure of the Safety Camera Partnerships the nationwide interchange of ideas and experiences could be diluted or lost.[209]

128. The change in funding arrangements for the National Safety Camera Partnerships ends the ring-fencing for camera operations. The police fear that under the new system their involvement could be sidelined and their access to funding might be curtailed. Transport for London in particular has concerns that it will be difficult to increase funds to expand camera enforcement even where cameras are the most effective solution. Camera Partnerships have provided valuable lessons in partnership working; the connections that have been made must not be lost. We will keep the new arrangements under review and hope to see that cameras continue to be an important part of casualty reduction for as long as they remain one of the most effective interventions.

Future technologies for speed limit enforcement


129. Safety cameras have proven very effective in reducing speeds and preventing casualties, but that does not mean that technological developments should stop there. Time-distance cameras have been very effective where they have been used, and their widespread deployment could have an important impact in further enhancing the effectiveness of camera enforcement and deterrence to speeding.[210] The cameras cover longer stretches of road. Times of entry to and exit from the zone can be recorded and compared with expected travel time if all speed limits within the zone were observed. The cameras could be used on high speed and low speed roads, including residential roads. Such cameras may be preferable to road engineering measures such as speed humps for a variety of reasons.

130. Transport for London is exploring the potential of time-distance cameras in enforcing 20 miles per hour speed limits on residential roads. The organisation suggests that time-distance cameras could allow 20 miles per hour zones to be introduced and enforced on London's 10,000 kilometres of residential roads within the next 10 years, rather than the 35 years it would take to install road humps. The organisation stated: "This is a real opportunity to halve casualties in London's residential areas, using self-funding measures. It will be vital, however, to allow the fine income to be retained in order to run the camera systems and fund new schemes."[211] TfL is in the process of securing Home Office type approval for the equipment.[212]

131. The Slower Speeds Initiative suggested that such a system would be considered fairer since drivers are not penalised for momentary violations.[213] It argued the cameras would also be more effective since the deterrent effect is active over a larger area and thereby secures more consistent compliance with the speed limit. It noted that the four-year evaluation report on safety cameras showed that time-distance cameras reduced speeding on average by 53% and completely eliminated 'high-end' offences (exceeding the speed limit by more than 15 miles per hour). The Police Federation also called for greater use of these cameras and indicated that current funding constraints had limited their use to date. It told us: "It would be far better in the interests of driver compliance to consider wider use of speed/distance devices. We acknowledge the expense involved, but we are concerned that better, more efficient technology is not being developed quickly enough."[214]


132. We also heard that intelligent road studs (IRS) may have potential to be used in speed enforcement. The studs protrude only 4 millimetres above the road surface yet can house lighting systems, weather and road conditions sensors, infra-red speed detectors and digital video cameras. They can collect and transmit data to roadside cabinets which can be connected to traffic control systems.[215] The studs are already in use in the UK and abroad as a cheap and effective means detecting weather and lighting conditions. The Slower Speeds Initiative told us:

IRS technology could combine vehicle activated driver information and warning systems with enforcement. Speeding drivers could activate warning lights indicating that they should slow down. If they failed to heed the warning, they could then trigger camera studs to record their speed and issue violation notices.[216]


133. Intelligent Speed Adaptation may also have a role in the near to medium future. Our predecessor Committee made recommendations on its application for safety purposes.[217] Intelligent Speed Adaptation is a system of in-vehicle speed limitation. The vehicle is located and provided with information about the speed limit on the road, through a combination of a Global Positioning System and a digital road map. This information is connected to the vehicle's power train: throttle, ignition, fuelling system, gearbox and brakes. The system provides in-vehicle technology which prevents the driver exceeding the speed limit, except in emergency situations.

134. Initial research in the UK, funded by the former Department of the Environment, Transport and the Regions and undertaken by the University of Leeds and the Motor Industry Research Association, identified that a full mandatory dynamic form of Intelligent Speed Adaptation would lead to a reduction of 36% in all injury collisions and of 59% in fatal crashes. There was support from many of our witnesses for its early introduction.[218] As Stephen Plowden commented:

There is something ridiculous about allowing excessively fast and powerful cars on the road and then trying, at great expense and with only modest success, to stop people from using that power.[219]

135. Speed cameras have achieved significant reductions in collisions and casualties. There remains potential to increase this impact not only through the rules and arrangements which govern their use, but also through ongoing technological developments. Time-distance cameras improve effectiveness: the Department for Transport, Home Office and police forces should take the steps necessary to encourage their use and make sure sufficient resources are invested. The possibility of using time-distance cameras to enforce 20 miles per hour limits on residential roads should be explored by the Department. We welcome Transport for London's efforts to secure Home Office type approval for such equipment in order to protect vulnerable road users through enforcement of appropriate speed limits. Development work on Intelligent Speed Adaptation should be continued. We would welcome the early introduction of in-vehicle enforcement technology. The potential of Intelligent Road Studs should also be further explored.

163   Ev 25 Back

164   DfT Road Casualties Great Britain: 2004 Annual Report, page 119 Back

165   Ev 150 Back

166   National Statistics 'Transport Statistics Bulletin: Vehicle Speeds in Great Britain'. Back

167   Ev 101 Back

168   'Regression-to-mean', sometimes called 'bias by selection', complicates evaluations at sites with high collision numbers (blackspot sites) in that these sites have often been chosen following a year with particularly high numbers occurring. In practice their collisions will tend to reduce in the next year even if no treatment is applied. Even if three-year accident totals are considered at the worst accident sites in an area, it is likely that the accident frequencies were at the high end of the naturally occurring random fluctuations, and in subsequent years these sites will experience lower numbers. See Road Safety Good Practice Guidance, Department for Transport, October 2001, paragraphs 5.119 to 5.123. Back

169   PA Consulting & UCL (2005) The national safety camera programme four-year evaluation report Back

170   Since the site selection guidelines for cameras include casualty threshold levels, it is likely that some of the observed reductions in collisions will be attributable to regression-to-mean effects. Back

171   Ev 73 Back

172   Ev 20 Back

173   Ev 68 "Distance halo" refers to the distance that the effects of enforcement last after drivers pass the enforcement site "Time halo" refers to the length of time that the effects of enforcement on drivers' speed behaviour continued after the police presence was removed. Back

174   Ev 81, 96, 69, 134, 25. Q91 Back

175   Ev 25 Back

176   Ev 96 Back

177   Ibid Back

178   Q12 Back

179   Q86 Back

180   Taylor, MC,Lynam, DC,Baruya, A (2000) 'The effects of drivers' speed on the frequency of road accidents' TRL 421 Back

181   Ev 101 Back

182   Ibid Back

183   Ev 150 Back

184   Ev 22, 86, Q256 Back

185   Ev 1 Back

186   Ev 86 Back

187   Q33 Back

188   Ev 51 Back

189   Q345 Back

190   Ev 150 Back

191   Ev 131, 25, 73 Back

192   Ev 25 Back

193   Corbett, C. and Caramlau, I. (2004) 'The nature and extent of excess speed in London and drivers' perceptions of safety cameras.' Commissioned by London Safety Camera Partnership Back

194   There is a 50 per cent chance of being killed at 35 mph compared to a 20 per cent chance of being killed at 30 mph. Back

195   Ev 131 Back

196   See Hansard, 15 December 2005, col 178WS. Back

197   Q347 Back

198   Q343 Back

199   Ev 101 Back

200   Ev 136, 28, 85, 101 Back

201   Qq 37, 275 Back

202   Ev 28 Back

203   Q275 Back

204   Ev 136 Back

205   Ev 1 Back

206   Ev 51 Back

207   Q160 Back

208   Ev 98 Back

209   Ev 85 Back

210   Ev 116, 119, 51, 25, 86, 98 Back

211   Ev 98 Back

212   Q283 Back

213   Ev 25 Back

214   Ev 51 Back

215   Ev 25 Back

216   Ibid Back

217   House of Commons Transport Committee Seventeenth Report 2003-04 'Cars of the Future' (HC 319-I) Back

218   Ev 116, 127, 129, 85, 44, 25, and Qq 5, 14, 266, 281, 283 Back

219   Ev 116 Back

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