The opinions expressed in the studies are those of the consultant and do not necessarily represent the position of the Commission.
Traffic law enforcement influences driving behaviour through two processes: general deterrence and specific deterrence. General deterrence can be described as the impact of the threat of legal punishment on the public at large. Specific deterrence can be seen as the impact of actual legal punishment on those who have been apprehended.
Generally, reviews report substantial positive effects of speed enforcement on both speeding behaviour and the number of crashes. The sizes of the reported effects of speed enforcement vary considerably. These differences most likely have to do with the type, intensity and location of the enforcement activities as well as the situation before the enforcement started.
Speed enforcement is most effective when it is unpredictable and difficult to avoid, when there is a mix of highly visible and less visible activities, and when it is continued over a longer period of time. Furthermore, it is advisable to focus speed enforcement on roads, situations, and times where speeding is considered to affect the road safety level most.
Speed enforcement is not a stand-alone measure. To maximise its effect, it is best supported by other measures such as credible speed limits and publicity. It is also important that speed enforcement is embedded in a supportive framework of legislation and sanctions.
Preferably, the police work together with partners to prepare, perform and evaluate (speed) enforcement activities. The main partners for the police are local road authorities, court officials, publicity organizations, and researchers. Local road authorities and researchers may assist the police in analysing the local road safety problem and determining priorities. Cooperation with court officials provides clarity about regulations for detecting and sentencing traffic offenders. Publicity organizations can organize supportive publicity programmes, in consultation with the police and the road authorities.
New vehicle technology can be integrated in the system of enforcement. For example, electronic vehicle identification (EVI) can be made part of the enforcement system and support this system. When cars are equipped with black boxes, it is possible to enforce speeding at all times and places. On the long term, police enforcement as we know it may be largely replaced by new technological systems of speed control.