Are Bicycle Helmet Laws Bad For Public Health?

Ask Martin Tanneberger what he thinks of mandatory bicycle helmet laws and you’ll receive a blunt answer.

“Not very much. I don’t really like them,” he sighs. “If you look at the rest of the world, and then you look at Australia and New Zealand – we’re the only two countries, as far as I understand, that have helmet laws … it’s slowing us down in terms of social riding and the leisure side of things.”

Tanneberger should know. As the managing director of The Bicycle Revolution, a retail outlet in the Brisbane inner city suburb of West End that specialises in the sale, rental and refurbishment of classic bikes, he’s deep in the trenches of Australia’s plucky cycle culture. “The target market for us is people who want to ride casually,” he says. “They don’t want to do it for a sport, so needing a helmet isn’t [imperative].”

The Bicycle Revolution has a permanent station of six bikes at a local YHA hostel. “Foreign travellers are confused by [the law],” Tanneberger says. “And they hate it when they have to buy a helmet, because they’re leaving again in three or four months. I say to them, ‘It’s up to you. You can wear a helmet or not wear a helmet. But you’ll definitely be caught.’

“I don’t have a problem with people wearing helmets for sporting reasons, as safety gear, and I don’t mind if children wear helmets. But then I don’t really like it when adults [have to] wear helmets riding to work. [The government’s] basically trying to make cycling seem like an extreme sport and that it’s really dangerous.”

These sentiments might seem obvious coming from a bike shop manager, who of course stands to gain from any repeal in compulsory helmet laws. But Tanneberger’s opinions align with a growing body of evidence that suggests bicycle helmet laws are not only ineffective and depress rider numbers, but may in fact be detrimental to long-term public health.

“Save a few brains, destroy many hearts.”

Mandatory bicycle helmet laws are now into their third decade of existence in Australia. John Cain’s Victorian government was the first to introduce the requirement in July of 1990, the move followed by other states and territories over the next two years. But it was the federal government pulling the strings, threatening a cut in road funding if the state governments failed to comply with a ten-point road safety program that included the helmet laws.

“It was point ten on the list,” says Chris Rissel, “and if you wanted to accept all the funding you had to introduce helmet legislation on a state-by-state basis. That was why it was introduced.”

Rissel is a professor in public health at Sydney Medical School and at the forefront of research that suggests Australian mandatory helmet laws are not only ineffective, but may in fact have a negative net long-term impact on public health. “I’ve been involved in cycling research for maybe ten years,” he says. “But it was only when someone showed me some data about the injury rates before and after the introduction of the legislation that I thought, ‘Wow, helmet legislation didn’t make much difference here.’ There are other [safety measures] that are more important. In fact, overseas most people think the Australian experiment is pretty conclusive. It doesn’t work, and they’re highly reluctant to introduce cycling legislation about helmets because of the adverse effect it has on cycling.”

Rissel says legislation hasn’t delivered the impacts in injury prevention that it was designed to: “For everyone to wear a helmet at all times on every trip is a significant impost on people. For that you’d want significant improvement in head injuries, and you simply don’t see that in the data.”

At the sharp end of Rissel’s assessment is a significant decline in cycling head injuries before the introduction of the legislation. Major changes to traffic environments – lower speeds, random breath testing – and a range of safety campaigning improved conditions for all road users. “What we see in the data is that there were improvements in head injuries … during that time. From the eighties down through to the nineties, it was all improving for everyone, including cyclists. And the helmet legislation coming in made very little difference overall.”

But perhaps more alarming is the growing body of evidence suggesting mandatory helmet laws are detrimental to long-term public health. Census data indicates an immediate decline in cycling rates upon the introduction of the legislation in the early nineties, and despite a recent upward trend real numbers have yet to recover in any state or territory other than the ACT. “When legislation was introduced there was a significant drop in people cycling straight away,” Rissel explains. “And you still have a negative effect of people having to wear a helmet that puts them off cycling. We did a survey [for the Health Promotion Journal of Australia] a couple of years ago where we asked 600 people, ‘Would you cycle more if you didn’t have to wear a helmet?’ And 25 percent of people said that they would. This was significant, because it includes all the people who don’t ride bikes or only ride them occasionally. That’s a massive number of people. And even if only some of those people did ride, it would literally have the effect of doubling or tripling the number of people cycling some time.

“So it has a massive retardant effect of participation in cycling. That is where you have the public health loss, because people aren’t cycling when they could – particularly for short trips and those people don’t think of themselves as a cyclist.”

(census data via

Rissel’s findings are backed by a number of studies around the world. As early as 1992 the British Medical Association enumerated a benefit to risk ratio for bicycling of 20:1, concluding that despite the hostile environment in which many cyclists rode at the time, the health benefits far outweighed the loss of life years in terms of injuries on the road.

More recently, a meta study produced by Professor Kay Teschke for the University of British Columbia Medical Journal found that “there is a large net health benefit of increased cycling, since the risk of fatal injury is greatly outweighed by the reductions in mortality afforded by increased physical activity.”

Closer to home, a 2010 statistical analysis conducted by Macquarie University Professor of Applied Finance and Actuarial Studies, Piet de Jong, turned up similar results. De Jong quoted Whistler, British Columbia physician Thomas DeMarco’s conclusion that helmet laws “save a few brains but destroy many hearts” in his paper, The Health Impact of Mandatory Bicycle Helmet Laws, which found that, “In jurisdictions where cycling is safe, a helmet law is likely to have a large unintended negative health impact.”

Unsafe jurisdictions

But, understandably, not everyone agrees with such an immediately counter-intuitive idea. Ben Thomson is a trauma surgeon at the Royal Melbourne Hospital and is firmly against any change in mandatory helmet laws.

“I would be. Personally, I don’t think it’s a problem wearing a helmet,” Thomson says. “I don’t think it adds too big an impediment to riding a bike.”

Thomson is in a unique position to view the different kinds of trauma cases admitted to Australian hospitals. In Victoria, the vast majority of adult cases are directed to one of two hospitals in the Melbourne CBD: The Alfred and the Thomson’s Royal Melbourne. “Bicycle trauma probably accounts for five to ten percent of that,” he says.

Thomson admits he hasn’t looked at the long-term health economics of bicycle helmets, but is meticulous in correcting a misinterpretation of how exactly bike helmets work. “There’s a formula for surviving an injury called the Gadd Severity Index,” he explains, “and it says that the injury actually happens from the distance you decelerate.

“The idea behind a bike helmet is not so much to protect a direct blow to your head. It’s to create a barrier, so that when your helmet hits the ground, your head then starts to decelerate maybe four or five centimetres from the concrete, rather than decelerating over a couple of millimetres or a centimetre at best.

“The most debilitating injuries we see – the most expensive injuries we have to fix – are brain injuries,” Thomson continues. “In the absence of a spinal injury we can fix a busted neck and that will get better with time, and we can fix most other things – broken bones, injured organs, they get better with time – but once a brain injury happens, you can’t really fix that. And often they’re they patients who end up with a debilitating and expensive recovery and often don’t return to work.”

But Thomson also admits that what stops him personally from getting on a bicycle is not the requirement to wear a helmet, but the fear of riding down a bike path that’s part of a major road. Which taps into a major argument of Professor Rissel and his colleagues: mandatory bicycle helmet laws are a cheap policy that allow state governments to eschew responsibilities in other areas of managing risks to cyclists.

“It is an incredibly victim-blaming policy,” Rissel says. “Because nothing is done to protect the cyclist other than make them wear bright colours, wear a helmet and look after themselves. And the cause of injury is often the speeding motor vehicle and not the rider themselves. As a government, it’s a very cheap way to look at road safety, but it’s not very effective. It’s cheaper than investing in bike paths and so on, and that’s where the biggest gains in safety can be found.”

Rissel also talks about the benefits of safety in numbers: as you get more people cycling, drivers learn to adjust their behaviour around the changed road conditions. “The chances are that they themselves would either walk or cycle at some point,” he says, “so they’d know what it’s like to be on the other end. So there’s definitely a safety-in-numbers impact. The deterrent effect of helmets and stopping the number of people riding has actually had a negative effect because of the safety in numbers phenomena. You’re making it twice as unsafe by reducing people by a third, as we’ve done.”

Thomson confirms that many of the bicycle trauma patients he sees are the unwitting victims in an accident. “The majority is that they’ve been hit by a car or a truck,” he explains. “There are a few other types of accident, such as people opening car doors in front of them, and there’s a few where they’ve actually hit other cyclists. But a minority of them are people coming off a bike where they actually haven’t been hit by something else … it’s not usually [people] riding crazily. Most bike accidents we see are just that they didn’t get seen, unfortunately, by whatever hit them.”

The rebound effect

Cameron Murray brings a different perspective to the bicycle helmet debate. An economist based in Brisbane, Murray has experience working with government policy via a stint with the Queensland Competition Authority, but completed a masters degree looking at rebound effects: the unintended consequences of policy decisions or behavioural adjustments.

“I couldn’t say decisively one way or the other whether bicycle helmets are bad for public health in the long-term,” Murray says. “I guess my gut feeling on a whole – having seen what other types of cycling environments you have around the world – is that probably the net effect would be a reduction in public health, if you include obesity and issues like that.

“The great thing would be to do some randomised trial where one city keeps helmet laws and another gets rid of them.”

Part of analysing rebound effects is looking at flow-on effects and deciding where exactly to draw the line of causality from one to another. “When you want to assess public policy we might say, Bike Helmet Law (A) and Flow-On Effect (B). Flow-On Effect (B) might itself have a Flow-On Effect (C), and Flow-On Effect (C) might have a flow-on effect through political processes, which is (D). But nobody knows exactly where you would draw the line of causality from (A).

“We ticked helmet laws and indirectly we have this flow-on consequence that governments now have little incentive to improve cycling infrastructure or promote cycling in other ways. So you literally can’t draw a line and say, ‘These are the consequences.’ But what you can do is say is that it’s a bit like a branching tree.”

Talk to Murray and you soon realise rebound effects are everywhere. He mentions studies that indicate bicyclists wearing helmets and gloves often ride faster. And another that pinned motorists as passing closer to helmeted cyclists and racing bikes than they do bareheaded two-wheelers. “It applies to any safety behaviour,” he says. “Anti-lock brakes: They did a famous study with taxis, where they gave half a fleet anti-lock brakes. And once drivers realised they had them, they drove faster, they crashed more and had to have more maintenance on the car. It was called the Munich Taxi-Cab Experiment.

“There was the effect on road deaths of the 9-11 terrorist attacks. Because all the aircraft were grounded, people drove cross country to get where they had to go – hiring cars and driving across states – so there was a large increase in road accidents that wouldn’t have been the case if people had flown. But that’s the general rule of public policy. You don’t really know until you’ve tried it what exactly is going to happen.”

Murray says that people – including his own friends – often refuse to believe that a safety icon like the bicycle helmet could potentially have a negative impact on long-term public health. “They might suggest you jump down the stairs without a helmet and see what happens. But that’s not the question,” he says. “The question is whether it changes behaviour in the aggregate. That’s a public policy question.

“If you wanted a bike helmet that really worked you could enforce motorbike helmet standards. But no one’s going to do that because they know [no one would ride bicycles]: ‘Actually, once I make the change bigger there’s a more obvious effect.’ But when the change is a little smaller, they can round down that effect to zero, despite it being large at the society level.”

Taking it to the man

But are state governments interested in engaging on this issue? TheVine reached out to the offices of Queensland Minister for Transport and Main Roads Scott Emerson – who in April pushed through an exemption to the state law for members of the Sikh community – and his Victorian counterpart, Terry Mulder, asking if any repeal of the mandatory helmet law or a more minor change in legislation was in the offing, and what kind of evidence it would take to force a change.

In a detailed response, a Queensland Transport and Main Roads spokesperson indicated that the government is not currently considering a change to mandatory bicycle helmet laws: “It is widely accepted that there are differing opinions on the effects of mandatory bicycle helmet legislation. However, the weight of the academic research supports the view that bicycle helmet legislation has had a positive impact on cyclist head injuries.”

The spokesperson refers to a number of studies indicating the efficacy of bike helmet laws when it comes to protecting riders during falls, including a 2010 CARRS-Q study and a 2011 study in the Accident Analysis & Prevention journal (which has since in the same publication been skewered by Professor Rissel) but provides little counter-argument to the claims made by researchers concerning the mandatory helmet law’s effect on long-term public health, except to say regular bicycle usage surveys “do not indicate the requirement to wear a helmet as a barrier to cycling.”

The spokesperson also refers to figures from 2010 suggesting bicycle fatalities as a rate per 100,000 are much lower in Australia than in countries that don’t have mandatory helmet legislation, such as the Netherlands, Belgium, Germany and Italy. But these figures don’t account for rider numbers, which are far higher in Europe, and also don’t match up against 2011 OECD figures, which indicate Australia’s 53 percent decrease in cycling fatalities since 1990 is in line with the group average but actually below many countries without mandatory helmet laws.

A spokesperson for Terry Mulder refers to the same CARRS-Q and Accident Analysis & Prevention journal studies before saying, “There is sufficient rigorous evidence, based on real on-road experience, that helmets reduce bicycle-related head and facial injuries for cyclists. The government does not therefore intend to repeal compulsory helmet-wearing legislation.” And in a robust response to the question of long-term health says, “Obesity is a public health issue with a range of contributing factors. To single out repealing helmet-wearing laws as a solution is simplistic and potentially damaging as it will put more riders at risk.”

Both the Queensland and Victorian ministries claim to regularly review the safety benefits of wearing bicycle helmets and monitor local and international research on the matter. “We want to increase cycling for school, work, recreation and shopping trips, including doubling the proportion of journeys to work by cycling across the state by 2021,” the Queensland spokesperson concludes. “The strategy provides a ten year plan to build cycling infrastructure, realise cycling’s contribution to transport and the economy and to create cycle-friendly communities.”

Back in West End, Martin Tanneberger agrees that the government is investing more money into cycling infrastructure. “It’s behind [European countries],” he says. “But it is getting better. We are seeing a marked improvement and more funding going towards cycling paths.”

But both Chris Rissel and Cameron Murray reckon helmet laws will continue to hold riding numbers back. “It’s tough to change politically,” Murray concludes. “I think there’s an emotional appeal, a satisfaction we get from thinking people are doing the right thing or being cautious. And that translates into lots of environments. For example, airlines – the security charade – we know it basically doesn’t work, but people like to see it and they feel comforted. No one’s going to drop that and no one’s going to drop helmet laws, unless there’s some sort of critical mass. Cyclists are keen on this, they’re passionate, and like to look into the evidence. It’s the non-cyclists who want to see others doing the ‘right’ thing.”

Matt Shea (@mrmatches)

(Lead image via Shutterstock) 

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5 comments so far..

  • srbryers's avatar
    Date and time
    Wednesday 31 Jul 2013 - 2:25 PM
    I entirely agree with this. I used to ride my bike to and from work without a helmet because it made it harder to see traffic, notwithstanding that fact that I wasn't going that fast anyway. Get rid of the helmet laws. Plus, if there were more people on bikes, there'd be less people on roads, quid pro quo - less accidents.
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  • burtthebike's avatar
    Date and time
    Wednesday 31 Jul 2013 - 9:52 PM
    An excellent article and summation of current thinking about helmets. The result of thirty years of this law have not been an improvement in the safety of cyclists, but a reduction in the public health. Unfortunately, politicians are incapable of admitting that they made a mistake, and won't repeal this law.

    Mind you, it would appear that the law is now impossible to enforce

    If you were to make the same case as Sue Abbot, case law would appear to exist that would make it extremely difficult to convict for not wearing a helmet.

    For those wanting to do more in depth research on cycle helmets, the website is the biggest collection of info on the web.
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  • MattShea's avatar
    Date and time
    Wednesday 31 Jul 2013 - 11:04 PM
    As Cameron Murray says, you'd think it would only take a massive amount of data to change the law.

    Perhaps one of the small slivers of hope for casual cyclists who don't want to wear a helmet is that the legislation was originally forced upon the states by the federal government.
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  • HisLordship's avatar
    Date and time
    Friday 02 Aug 2013 - 9:58 AM
    Well, I don't know all the ins-and-outs of public policy and so on, but I do no that when my bike skidded in some side-of-the-road detritus and I went flying into the concrete and planted head-first, my helmet was smashed up but my head wasn't.

    Since then I don't even consider getting on the bike without my lid.

    But the most telling bit of this column is the graph by state. The ACT, with its decent off-road cycle pathway infrastructure, has taken off. Funny that. (I won't put that down to the larger numbers of younger people, educated people and Green voters that the ACT has, obviously.)
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  • harvey7's avatar
    Date and time
    Saturday 03 Aug 2013 - 1:54 PM
    An interesting piece Matt. You obviously put a lot of research into it.

    This bit is not entirely accurate though: “Save a few brains”

    It is a myth that bicycle helmets protect against severe brain injury. Severe brain injury is caused by rotational acceleration, that helmets cannot protect against.

    It is a fallacy to presume that a bicycle helmet law is a trade-off between safety and health. Wherever is has been attempted, bicycle helmet laws have resulted in an increased risk of injuries, including head injuries.

    What about the “rigorous evidence” that helmets protect, according QLD department of transport? It is based on the sham CARRS-Q “research” quoted, commissioned and even edited by the QLD department of transport. If you need supportive “research”, why not write it yourself?

    The claim from the QLD department of transport that cycling in Australia is safe based on numbers per population, rather than per km cycled, indicates they are treating us like fools. In reality, Australia combines one of the lowest levels of cycling with the highest rate of death and injuries, consistent with the well-established “safety in numbers” phenomenon.

    The QLD government is using desperate tactics to try to cover up the failure of its helmet law. What it fails to acknowledge is the large increase in the risk of accidents after the helmet law. That could not be compensated by a piece of styrofoam. The risk of death & serious injury for cyclists increased significantly. Despite that, the bureaucrats still waste public funds commissioning “research” to spin their propaganda that their helmet law is backed by “evidence”

    Don’t be fooled, there is no trade-off between safety and health when it comes to bicycle helmet legislation. The bicycle helmet law has damaged both. It is overdue that we reform this counterproductive law.

    The bureaucrats should not get away with deceit.
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