• helmet laws
• cycle

Except for one study reporting decreased cycling by children aged 12–17 in Victoria, Australia, Macpherson et al stated: “no other study about the relationship between legislation and exposure to cycling has been published”.¹ Macpherson’s paper has already been cited several times as evidence that helmet laws do not discourage cycling, so it is important to examine the evidence.

In fact, several published studies of cycle use and helmet laws are cited and described in refereed journals. Some were attitude surveys. The equivalent of 64% of adult cyclists in Western Australia said they’d ride more except for the helmet law.^2,3 In New South Wales (NSW) 51% of schoolchildren owning bikes, who hadn’t cycled in the past week, cited helmet restrictions, substantially more than other reasons, including safety (18%) and parents (20%).⁴ Street surveys by cyclists’ organisations in the Australian Capital Territory and Northern Territory found 28%–42% of cyclists would ride less/had ridden less because of helmet laws.³

Large scale roadside counts were also conducted. Pre-law surveys counted 6072 child cyclists in NSW,^3,5 3121 cyclists (all ages) in Victoria;^3,6 and over 200 000 cyclist movements on two key routes in Western Australia.³ Equivalent counts a year after enforced helmet laws showed declines of 36% (NSW), 36% (Victoria) and 20% (Western Australia).^3,5,6 Sunday recreational cycling in Western Australia (24 932 cyclists pre-law) dropped by 38%.⁷ Increases in numbers wearing helmets, 1019 (NSW) and 297 (Victoria) were substantially less than declines in numbers counted (2215 and 1110).³ These surveys were at the same time of year, in similar weather, and used the same sites and observation periods, so can be considered reliable indicators that enforced helmet laws discourage cycling. Reduced cycling activity is associated …