Enforcement of speed limits--actual policy and drivers' knowledge.

This paper reviews the penalty rules and examines drivers' perceptions of enforcement of speed limits. The survey was carried out using a sample of 204 Norwegian drivers, answering questions in a setting closely associated with their driving situation. For minor speeding offences drivers overestimated on average their fines. For serious speeding offences drivers significantly underestimated how many kilometers per hour they could exceed the speed limits before losing their driving license. They also overestimated the probability of being caught speeding. This resulted in a perceived expected penalty twice the real one. The paper also examines the relationship between different driver characteristics and their knowledge of the enforcement policy for speeding. Older drivers had less knowledge about the threshold level for serious speeding but more knowledge about the detection rate than younger drivers do. Experienced drivers had more knowledge about the threshold level for serious speeding than inexperienced drivers. The number of times drivers were stopped due to speeding offences increased their knowledge of fines for minor speeding.