Thursday, 22 March 2012

Compulsory Helmet Laws and Current Safety Measures Shown Up

A study done in Australia a little after the compulsory helmet laws were brought in (early 1990s) shows the hypocrisy and failure to follow evidence. The text abstract is here, but it is a little unwieldy. I've tried to punctuate it into bullet points below, whilst maintaining the full text.
  • The first year of the mandatory bicycle helmet laws in Australia saw increased helmet wearing from 31% to 75% of cyclists in Victoria and from 31% of children and 26% of adults in New South Wales (NSW) to 76% and 85%. 
  • However, the two major surveys using matched before and after samples in Melbourne (Finch et al. 1993; Report No. 45, Monash Univ. Accident Research Centre) and throughout NSW (Smith and Milthorpe 1993; Roads and Traffic Authority) observed reductions in numbers of child cyclists 15 and 2.2 times greater than the increase in numbers of children wearing helmets. This suggests the greatest effect of the helmet law was not to encourage cyclists to wear helmets, but to discourage cycling. 
  • In contrast, despite increases to at least 75% helmet wearing, the proportion of head injuries in cyclists admitted or treated at hospital declined by an average of only 13%. The percentage of cyclists with head injuries after collisions with motor vehicles in Victoria declined by more, but the proportion of head injured pedestrians also declined; the two followed a very similar trend. 
  • These trends may have been caused by major road safety initiatives introduced at the same time as the helmet law and directed at both speeding and drink-driving. The initiatives seem to have been remarkably effective in reducing road trauma for all road users, perhaps affecting the proportions of victims suffering head injuries as well as total injuries. 
  • The benefits of cycling, even without a helmet, have been estimated to outweigh the hazards by a factor of 20 to 1 (Hillman 1993; Cycle helmets—the case for and against. Policy Studies Institute, London). Consequently, a helmet law, whose most notable effect was to reduce cycling, may have generated a net loss of health benefits to the nation. 
  • Despite the risk of dying from head injury per hour being similar for unhelmeted cyclists and motor vehicle occupants, cyclists alone have been required to wear head protection. Helmets for motor vehicle occupants are now being marketed and a mandatory helmet law for these road users has the potential to save 17 times as many people from death by head injury as a helmet law for cyclists without the adverse effects of discouraging a healthy and pollution free mode of transport.
My analysis of this is as follows.
  1. Helmets do very little to protect cyclists in car-bike collisions.
  2. Reducing head injuries is better done by dealing with misbehaving motorists.
  3. Helmets would do an enormous amount more to protect car occupants. Where is the cry to have them wear helmets?
Of course that last point is simply meant as a jibe and not to be taken seriously. From other studies it is known that the more that car drivers (and occupants) are coddled up and protected from the violent disturbance their vehicle is causing outside, the more danger they cause to others. Risk Displacement describes this well.

Talking of other studies, we have Dr Ian Walker's study showing that wearing a helmet increases the danger to cyclists as motorists give less space. And the simple fact that helmets are designed for impacts of 12mph and less, equivalent to a fall off a bike, shows that all this bluster about helmets is a complete distraction from safety on the road.

If the same money used to perpertuate (and police in some places) the myth that helmets help in bike-car collisions was spent on measures that might make a difference, we may have a lot more lifes saved than we do currently. Essentially this focus is costing lifes.

This is also a message for Red Light Jumping policing. Not that I favour jumping red lights, but it such an insignificant factor in safety for cyclists, motorists, and pedestrians as to be another waste of time and money. Why are we spending time and effort on dealing with cyclist-fault collisions (around 7% of all bike-car collisions) whilst generally ignoring the 13 times as many driver-fault collisions? And even looking at pedestrians put at risk by cyclists or drivers, evidence (follow links here) shows that they are 40 times more likely to be hurt by a car than a bike. Again, if the same money was spent on measures that might make a difference, we may have a lot more lifes saved than we do currently. Essentially, again, this focus is costing lifes.

So, in summary, the kneejerk response to helmets and policing we are currently doing is costing lifes. All in a desire to be perceived as making the street "fair for all" whilst perpetuating the inequality of it.


  1. Trouble with the pedestrian-injury link is that, much like Mike Penning's statement not so long ago, it's not scaled using the frequency of occurrence of footway cycling (or driving). It tells us what's more likely to happen to a pedestrian, but that's not a useful measure of how dangerous the vehicle in question is when it's being operated on the pavement, and so isn't a useful statistic for informing enforcement priorities.

    Sure, common sense tells us that a motor vehicle should be more dangerous (and I'm sure that if we had statistics for total km cycled or driven of footways the motor vehicles would continue to cause more KSIs per km), but as far as I can tell the CTC-collated figures don't in themselves support or refute that.

    If I've missed something obvious, please tell me and junk this comment, as I'd hate to be Wrong On The Internet! ;-)

    1. Hmm, yes, I do get the point, and you are not wrong. If you want to look at the figures that way, they are included in the CTC document.

      However, what I wanted to do here was highlight the commonly held myth that it's cyclists who create massive amounts of danger whilst drivers somehow aren't responsible for the damage they cause. It's plastered all over the news about RLJing cyclists on the pavement terrorising pensioners and small children, whereas the poor old motorist is simply stuck in a bad system that caused them to kill & injure many, many people, they couldn't help it of course!

    2. Yep - not to mention the on-road incidents that don't involve a RLJ but do involve 'normal' carelessness, most of which have the standard of driving of motorists of one form or another as a proximate cause.

      I just like the points that we (as people who do give a damn about human-friendly transport) raise to be as un-pickable as possible (even when the arguments from the motoring lobby are just stalling tactics in sheep's clothing.)