Sunday, January 31, 2010

Do Helmet Laws Mean Less Bicycling?

There is no disputing that bicycle helmet laws for children have prevented many injuries and fatalities (19% fewer fatalities). According to a study by the National Bureau of Economics, there is an unintended consequence to these laws--less bicycle riding by children.  The evidence strongly suggests that children ride bikes 4-5% less as a consequence of helmet laws.  Researchers are unsure why the laws result in less bike riding--it could be that the cost of helmets deters parents, the look and feel of the helmets puts off kids, or perhaps the laws create a perception that bicycle riding is more dangerous.

Since 1994, Massachusetts has required kids 12 and under to wear bike helmets (note that some places like Cambridge have ordinances requiring helmet usage for older kids--up to age 16 in Cambridge).  When enacted, the law was actually somewhat controversial, but not because people thought it would result in fewer bike trips.  The League of American Bicyclists actually opposed children-only helmet laws back then.  Critics thought children only helmet laws sent the message that helmet usage was only necessary for children and not adults.

Helmet use has clearly become the norm for enthusiasts and racers, but I still see a lot of adults tooling around their neighborhoods on bikes without any helmet on.  Sometimes they are riding with their helmeted kids, sometimes they are headed out for an errand.

Actually, a Dutch family moved to my neighborhood a few years ago and scenes like this were pretty common at first:

This picture, which is pretty shocking to American eyes, shows a pretty common scene in Holland.  Maybe it shouldn't be such a surprise that bicycle usage has declined here as a result of helmet laws, but safety must come first.

1 comment:

  1. About 5% is what I've heard. There's a link to another study, much quoted at present since it went onto the Freakanomics blog.
    On page 31, there is a graph dipping from 0.85% to 0.75% and back up again. It shows states with helmet laws versus those without helmet law.
    What you can see is: practically no-one cycles (<1%). And the difference between the states is 5% of almost no-one. The last point is 0.75% for helmet law states versus about 0.775%. The greatest variations have nothing to with laws, as both sets of states vary by about 15%. That is the greatest differences in ridership have nothing to do with helmets. Current trends trump the minor inconvenience of a helmet.