Legislation mandating minimum distances for motorists passing cyclists is seen by advocates as a straightforward way to increase the perceived safety of cycling and thus remove a prominent barrier to the uptake of cycling. The evidence, however, is not as clear. The alternative to compliance-based enforcement via Minimum Passing Distance Laws (MPDLs) is performance-based enforcement as recently highlighted by UK Police forces under the name ‘Operation Close Pass’. This existing legislation and enforcement method relies on police officer judgement and discretion. For a MPDL to be introduced it has to show an improvement by identifying more manoeuvres that make cyclists feel unsafe, whilst at the same time not penalising drivers for manoeuvres that are benign. This study uses Signal Detection Theory to show that on almost every measure the current performance-based enforcement is preferable. Officer discretion is aligned more closely to cyclists’ real-world perceptions of risk than an objective, compliance-based MPDL. Any level of enforcement harshness can be achieved equally well, if not better, through officer discretion than through a fixed passing distance law, with the former being significantly easier to adjust if needed. Further discussion about the unintended effects of passing distance laws is discussed, such as the risk of a net loss to the effectiveness of cyclist safety because it is more difficult to prosecute and enforce manoeuvres which make cyclists feel unsafe than the performance-based alternative.
|Number of pages||15|
|Journal||Transportation Research Part F: Traffic Psychology and Behaviour|
|Early online date||11 Apr 2020|
|Publication status||Published - Apr 2020|
Lamb, J. S., Walker, G. H., Fisher, V., Hulme, A., Salmon, P. M., & Stanton, N. A. (2020). Should we pass on minimum passing distance laws for cyclists? Comparing a tactical enforcement option and minimum passing distance laws using signal detection theory. Transportation Research Part F: Traffic Psychology and Behaviour, 70, 275-289. https://doi.org/10.1016/j.trf.2020.03.011