Mandatory bicycle helmets: does correlation mean causation?Posted: November 1, 2011
It’s evident from the response to my article two weeks ago (Is the mandatory helmet debate a distraction?), that some people still see compulsory helmets as one of the major obstacles, perhaps even the main obstacle, to significantly higher uptake of cycling in Australia. So I want to look at the main arguments for repealing the compulsory helmet law.
As I’ve said before, I accept that mandating helmets in the early 90s was arguable policy, at least in the case of adults. If it were proposed for the first time today, I doubt it would get up (except for children). So I don’t think those who advocate repeal are necessarily “wrong”.
But in my view the helmet law is not the main thing holding cycling back in this country – it doesn’t even come close. And since it’s got virtually no traction politically, it’s also a waste of energy. Ultimately it distracts from the key issue – the danger, whether perceived or real, of cycling in traffic.
A key argument made by many repeal advocates is that countries without mandatory helmet laws have high bicycle use. Australia, in contrast, has both low mode share and draconian helmet laws; ipso facto, they say, mandatory helmet laws are the key problem.
What I think is happening here is the familiar problem of confusing correlation with causation.
There’s no doubt bicycle use in Australia is indeed low compared to some other countries. For example, according to Pucher and Buehler in Making cycling irresistible: lessons from the Netherlands, Denmark and Germany, bicycles capture 27% of all trips in the Netherlands and 18% in Denmark, but a mere 1% in Australia (see exhibit). And there’s no doubt helmets aren’t considered important in these countries – in the Netherlands, for example, less than 1% of adults and only 3-5% of children choose to wear a helmet when cycling.
But does the law on helmets explain why cycling is so much more popular in these countries than it is in Australia?
The first thing the repeal advocates should ask themselves is this: why are only 1% of trips in the UK taken by bicycle even though helmets aren’t mandatory in that country? That’s no better than here! Or why is cycling’s mode share only slightly better in Ireland and Canada than it is in Australia, even though these two countries don’t have mandatory helmet laws? Clearly, whatever the explanation is for the comparatively low rates of cycling in these countries, it has nothing to do with any compulsion to wear a helmet.
They should also ask themselves why there are such enormous differences between countries where helmets aren’t mandatory. The fact that bicycle use is more than twice as high in the Netherlands as it is in Germany – and nine times higher than it is in France and Italy – suggests pretty clearly that there are other highly influential factors affecting the propensity to cycle that have absolutely nothing to do with helmets.
Helmet policy doesn’t explain why bicycles capture 34% of trips in Munster, but 13% in Munich. Or why the corresponding figure for Groningen is 37% compared to 10% in Heerlen; or 20% in Bruges but 5% in Brussells; or 19% in Salzburg but 3% in Wien.
Rather than focussing so much on helmet laws, repeal advocates would do well to look at the differences in cycling infrastructure and regulation – and hence in safety – between Australia and Europe’s top performing countries. They should note that Copenhagen, for example, has an impressive 400 km of completely segregated bike lane, even though it’s much smaller than Melbourne. And Berlin has 860 km of completely segregated bike lane. They should also look at factors like 30 km/hr speed limits in residential areas in some countries and the strong cultural and legal onus on drivers to respect cyclists.
Pucher and Buehler argue the key reason cycling is so successful in Dutch, Danish, and German cities relative to other places (not just Australia) is down to extensive systems of separate cycling facilities, intersection modifications & priority traffic signals, traffic calming, bike parking, coordination with public transport, traffic education & training, and sympathetic traffic laws. They also point to the positive way cycling is promoted in these countries.
It’s no wonder people cycle more in Copenhagen and Berlin than in Melbourne and Sydney. And it’s no wonder they don’t bother to wear helmets – it’s much less dangerous! Yet even so, Danish and German authorities extensively promote wider helmet use, especially by children.
Put another way, the reason Dutch, Danish and German cities have high levels of cycling isn’t because riders aren’t compelled to wear helmets. Rather, riders don’t wear helmets because they’re not necessary. And they’re not necessary because cycling’s an order of magnitude safer than it is in Australia, thanks to the myriad infrastructure initiatives and supportive policies like those identified by Pucher and Buehler.
Repeal advocates invariably fall back on the argument that cycling use collapsed in Australia when mandatory helmet laws were introduced in the early 90s. There was indeed a collapse – bicycle use by 12-17 year olds fell 44%. However, cycling by 5-11 year olds fell by a more modest 10% and cycling by adults actually increased (doubling in metropolitan Melbourne)!
In any event, that was 20 years ago – that cohort of young teens moved on long ago, taking their ideas of what’s “cool” with them. Since then cycling for recreational purposes has gone gang busters. A million bicycles were sold each year between 2001 and 2009 in Australia. If mandatory helmets are such a deterrent, how come recreational cycling – which is very much a discretionary activity – has boomed since the 1990s?
I think helmets are more of an issue in relation to the failure of Melbourne Bike Share (although not the primary cause), but it’s important to understand that it’s getting access to a helmet that’s the problem with the Bixis, not the fact of having to wear one. Some perspective is needed here too – there are 600 Bixis in Melbourne, but millions of bicycles in residents’ homes. It’s the latter that matters most for Melbourne’s future.
There’s merit in the argument that mandating helmets was probably a mistake, but I very much doubt it’s a significant deterrent to cycling. It’s a second order issue. The big obstacle to more cycling in Australia is road safety, not mandatory helmets. Let’s get our priorities in order and focus on the main game.