Evaluation of the minimum passing distance road rule trial in Queensland, Australia

Minimum passing distance (MPD), or three-foot, laws have been introduced in several countries to reduce the occurrence and severity of crashes occurring when motorists overtake cyclists. However, research into the effectiveness of these laws is lacking. This study was an evaluation of a 2-year trial of a MPD rule in Queensland, Australia. The evaluation comprised of four components; (i) Police officers (n = 21) were interviewed to evaluate the practicality of implementing the rule; (ii) Motorists (n = 4,332) and cyclists (n = 3,013) were surveyed to assess their awareness, attitudes and self-reported compliance; (iii) passing events (n=3,202) were observed at 15 urban, regional, and tourist locations on South East Queensland roads to assess compliance with the rule; (iv) analysis of police crash, injury, and infringement data. Police reported that the rule was difficult to enforce and many motorists surveyed doubted their ability to accurately judge lateral distance. Just over half of the motorists (52.5%) and almost all cyclists (94.7%) agreed with the rule. Most motorists and cyclists surveyed had observed motorists giving cyclists more space when overtaking than 12 months earlier. The observed non-compliance rates were 12.1% at low speed sites (60 km/h or lower speed limits) and 20.9% at high speed sites, suggesting that compliance with the MPD rule was relatively good. It is premature to draw conclusions regarding the road safety benefits of the road rule given the lack of pre-implementation data and detailed crash and injury data. These initial findings, however, suggest that the MPD road rule encourages motorists to provide more space to cyclists and as such, improves cyclist safety.