Intended and Unintended Consequences of Youth Bicycle Helmet Laws
Associate Professor of Economics & Public Policy Chris Carpenter and Associate Professor of Economics Mark Stehr recently examined the effects of mandatory bicycle helmet laws on bicycling fatalities, helmet use, and cycling behaviours amongst youths in the USA.
The study was based on the differential timing of adoption of helmet laws across states, effectively identifying the helmet law effects from within-state changes in outcomes for residents of states adopting laws compared to the associated within-state changes in outcomes for youths in places that did not adopt a law in that same year.
The key findings of the study were:
- US helmet laws increase helmet usage by 29-35%.
- Helmet laws decrease cycling participation. This decrease was only modest for the 5-15yo age group but significant for the 16-30 age group.
- There was no correlation between helmet laws and cycling fatalities amongst cyclists aged 16 and over.
- Helmet laws correlated with a 19% reduction in cycling fatalities amongst children under 15, although this ‘estimate has a relatively large standard error, such that [we] cannot rule out that the true fatality effect is substantially smaller than our reported estimate’.
- Helmet laws significantly increase the social and psychological cost of cycling relative to other transport options.
- A significant part of the fatality reduction associated with helmet laws is the result of helmet laws discouraging cycling participation.
While the affects of helmet laws on cycling levels in the US has not been as strong as in Australia, it should be noted that the helmet law dogma is not as entrenched in the US as in Australia. Even in states with youth helmet laws, approx 1/3 of youth cyclists still do not wear them. Enforcement of helmet laws there is inconsistent and penalties for non compliance are modest such as verbal warnings, counseling, or a small fine. This is a stark contrast to helmet enforcement in Australia where penalties are typically around $150 and police use extreme measures to ensure compliance.
Journal article at http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1537776, PDF