The Helmet Wars (Sound Bite Version)


Related links: De's Bicycle Page and Alternative Transit Page,
The Barnes NYT Article
Meditations on the Helmet Wars,
Do Helmets Work?
Post Hoc Ergo Propter Hoc (how statistics can be overinterpreted)
Bad Science and Traffic Safety Policy
Some URLs for Reference
Some Common Beliefs about Bike Helmets
Making Cycling Safer

My larger, rambling essay leans on several points which you may or may not believe: that bicycling is not particularly dangerous; that automobile use is far more dangerous, in many ways both direct and indirect; that our society stigmatizes and marginalizes people who don't own or drive cars; and that it is this social stigma, rather than any objective statistical analysis of risk, which motivates "helmet hysteria" and MHLs. These soundbites offer glimpses into the enormous world of official statistics, scholarly papers, and advocacy publications available to the online researcher into bike safety issues. I believe they support at least some of my assertions, or at least indicate that there is another point of view to be considered before concluding automatically that (a) bicycles are hazardous and (b) therefore bike riders need to be forcibly helmeted for the good of society.
Safety is not as sweet and innocent as motherhood and apple pie. Rather, it is an apple of discord and it would be wise to be cognizant of this fact.

-- G. J. S. Wilde, Target Risk 2


Most of us, for instance, don't think twice about taking a walk, even though there is a 1-in-40,000 chance we will be killed as a pedestrian this year. Riding a bicycle is less risky, where we run about a 1-in-130,000 chance of being killed...

Most of us find that as risks get more remote than about 1 chance in 10,000,they become difficult to visualize. Here is a very rough rule of thumb for turning such ratios into more intelligible units: an annual risk of death of 1 in a million amounts to the equivalent risk of dying in a car crash if you travel in your car only 1 mile a week for a year; an annual risk of death of 1 in 100,000 poses the same risk as driving your car about 10 miles a week; an annual risk of death of 1 in 10,000 is about the same as what you run if you drive your car about 100 miles a week... another easy-to-understand baseline is this: a risk of 1 in 100,000 is the risk that the average 65-year-old woman runs that she will die within the next hour. In short, all these risks are very small indeed.

-- Larry Laudan, The Book of Risks


It is difficult to compare the exposure-corrected risk of injury to cyclists because of the difficulties involved in measuring the amount of cycling that occurs . . . These difficulties ensure that the amount of cycling is underestimated and therefore the accident rate of cyclists is overestimated.

One of the few studies that has attempted to measure the time-exposure of cycling in Australia was performed by the Monash University Accident Research Centre in 1988 (Drummond and Jee 1988) . . . indicates the risk of injury is substantially lower for cyclists than for common sporting activities.

[Bargraph shows injuries per 100 hrs risk factor. 0.19 for football, 0.13 for squash, 0.11 for basketball and netball and 0.06 for soccer. Cycling: 0.005 ]

If increased physical activity is to be adopted for improved public health, then cycling is ideal because of this low rate of injury.

-- Pedaling Health by Roberts, et al.


In 1996, 5744 Albertans died of cardiovascular disease. There were 22,268 injuries (549 cyclists and 1002 pedestrians) and 349 deaths in traffic mishaps (4 were cyclists and 36 were pedestrians). In 1996, for every cyclist that died, 1436 Albertans died of cardiovascular disease, 77 motorists died and 9 pedestrians died. Alberta's population was 2,636,489 in 1996.

-- Don Hollingshead, 'Helmet Law Concerns,' Alberta Bicycle Association, June 1999


Cyclists were the only group of road users in Britain whose death rate increased sharply during the 1990s, yet cycling was in decline throughout the decade. How could this happen, when attention on casualties was the most intense in the history of the bicycle?

Recent safety campaigns have destroyed faith in the bicycle as a safe means of transport, reducing participation, compromising public health, increasing the risks, and decreasing road skills.

. . . A recent study in Glasgow estimated that 150,000 people are admitted to hospital annually with head injuries in the United Kingdom; road cyclists account for only 1% of this total, yet 6% of the population are regular cyclists and a further 5% are occasional cyclists; 60% of admissions were alcohol related. Do we need revelling helmets?

[Editorial note: this is a really excellent paper, and I am tempted to quote the whole text. It probably debunks more automobile-centred mythology in fewer words -- and wittily -- than any other single research paper I know of.]

-- Malcolm J Wardlaw, Three lessons for a better cycling future,
British Medical Journal Dec 2000


According to John Hopkins, there are 300 injuries per million bicycle trips and 1.8 billion cycling trips per year. This works out to about 540,000 injuries per year, but even if we assume that each cyclist has an cycling trip every day, that is an average of over nine years between injuries for each cyclist.

The number of cycling head injuries requiring hospitalization (from the same source) is 7,700 per year or about 1.5% of the total cycling injuries (about 630 years between head injuries of this severity), and John Hopkins estimates the number of deaths due to head injuries by cycling is about 70 to 80% of the total cycling deaths or say 560 to 650 head injury deaths per year (about three million trips per head injury death, or 8,427 years between these fatalities, assuming a trip every day).

From the Caregiver web site, I learned that, in the US each year, there are a total of 500,000 to 750,000 hospitalizations due to head injuries and 75,000 to 100,000 head injury deaths. Thus, bicycle head injuries constitute only about from 1.02% to 1.54% of the US total serious head injuries and from .56% to .87% of the head injury deaths. The largest group of head injuries, by the way, are among motorists. Therefore, bicycling is not dangerous, nor is it a leading cause of head injury.

. . . Cycling is no more dangerous per hour than taking a walk or riding in a car (and most deaths in those cases result from head injury) and much less dangerous than other common activities. Should we wear a helmet everywhere we go?

-- Ken Kifer, 'Why I am Opposed to Mandatory Helmet Laws'


There is no evidence that hard shell helmets have reduced the head injury and fatality rates. The most surprising finding is that the bicycle-related fatality rate is positively and significantly correlated with increased helmet use.

-- Conclusions of a survey of 15 years and 8 million cases of American cyclist injury/fatality incidents
by G.B Rodgers, Journal of Products Liability 1988, vol 11, pp. 307-317


Despite what the Insurance Institute for Highway Safety and a number of other organizations that rely on data from the Fatality Analysis Reporting System (FARS) seem to think, there is no basis for the claim that the overwhelming majority (i.e. 95+ percent) of bicycling fatalities continue to occur to unhelmeted riders.

Riley R. Geary, Institute for Traffic Safety Analysis
Re-examining FARS Bike Helmet Data


Until the mid 1980s helmet use was rare amongst British cyclists. Helmet use started to grow from about 1986 but take-up was slow for some years. By 1996, however, helmet use had risen to an average of 16% throughout Britain, and was about 18% in 1998.

A growth of around 16% in helmet use over a decade is significant, and might be expected to result in a noticeable impact on recorded casualties to cyclists. However, for Great Britain as a whole, the trends in fatalities, serious injuries and severity ratio show no evidence at all of a 'helmet effect', in all cases trends continuing as they had prior to helmet use becoming more popular. Indeed, what change there has been in severity ratio would suggest that the proportion of serious injuries actually increased during the time of greatest helmet take-up.

-- John Franklin Trends in cyclist casualties in Britain with increasing cycle helmet use


Automobiles kill more than twice as many elderly New Yorkers than murderers do.

-- Killed By Automobile a report from NYC


Research by the World Health Organization (WHO) indicates that emissions from car exhausts are responsible for more deaths than road accidents themselves. The WHO study reviewed data from Austria, France, and Switzerland and found that exposure to pollution caused an estimated 21,000 deaths a year in the three countries alone. The researchers also calculated that car emissions caused 300,000 extra cases of bronchitis in children and 15,000 extra hospital admissions for heart disease exacerbated by pollution. Despite these problems, motor vehicle ownership is increasing at a staggering rate, with the fleet in China doubling in about five years.

-- UNEP news released quoted in Car-Free Times, March 2000


All pollution should give us cause for concern, especially background CO. A recent test on a cyclist who had pedaled around central Bristol for 20 minutes on a day when pollution levels were within so called "acceptable" limits found that he had a CO level in his blood equivalent to having smoked 5 cigarettes. Now, I ask you, is or isn't that a cause for concern?

The Grim Reaper
(Pseudonym of British cycle advocate Tony Ambrose)


Every parent's nightmare: a child stricken by cancer. It now appears that growing up near a transportation corridor with more than 20,000 daily vehicles causes a six-fold increase in the cancer risk for children, according to a new study conducted in the sprawling Denver metropolitan area.

-- Environment News Service article 'High Traffic Streets Linked to Childhood Cancers' Mar 2000

[Editorial note: traffic on Mission Street, the "main drag" on my side of the town of Santa Cruz CA, runs between 21,000 and 58,000 trips per day (varies by intersection)]


In New York City in 1990, motor vehicles were involved in 187,503 accidents, pedestrians in 15,460 accidents, and bicycles in 3,706 accidents.

-- Bicycle Blueprint of the Transportation Alternatives project in NYC.


Motor vehicles cause thirteen percent of all injury deaths in San Francisco and seven percent of all injury hospitalizations. Two percent of the deaths caused by motor vehicle crashes are bicyclists and three percent of these hospitalizations are bicyclists. In comparison, the proportion of motor vehicle crashes that resulted in pedestrian death and hospitalization are 25 percent and 32 percent, respectively, and the motorcycle deaths and hospitalizations are 3 percent and 27 percent, respectively... Of the 164 911 responses to bicycle injuries, 122 or 74 percent involved an automobile.

[Editorial note: therefore, bike/car injury deaths of cyclists constitute two percent of thirteen percent, or .13 x .02 = 0.0026 -- a quarter of one percent of all injury deaths in the city. And bike/car injury cyclist hospitalizations are three percent of seven percent, or .03 * .07 = 0.0021 -- an even smaller proportion. Furthermore, these very small death/injury stats represent 74 percent, almost 3/4, of the total 911 calls for bike accidents.]

Hospitalizations [from traffic accidents, percentages] July 1990 - June 1991
bicyclist 3
motorcyclist 27
pedestrian 32
motor vehicle occupant 38

Deaths [from traffic accidents, percentages] 1986 - 1991
bicyclist 2
pedestrian 25
motorcyclist 3
motor vehicle occupant 70

[from 1989 to 1993 there were 10 traffic accidents fatal to a cyclist:] The police reports attributed the party at fault in two of the fatal accidents to be the motor vehicle driver. In the first case the cause of the accident was a parked vehicle starting when unsafe. In the second case, the cause was the motor vehicle travelling at an unsafe speed. In neither case did the driver receive a citation . . .

The causes of the remaining eight accidents were attributed to the bicyclists. A bicyclist travelling at an unsafe speed was considered a primary or contributory factor in three collisions, running a STOP sign was the primary cause of one collision, passing on the right was a primary factor in two collisions, turning the wrong-way onto a one-way street was the primary factor in one collision, and a bicyclist veering into and side swiping a tractor trailer reportedly caused one collision. It should be noted that the bicyclist's version of the accident is not provided in these eight reports as they were all fatal collisions.

-- Chapter 3 of the San Francisco Bike Plan (undergoing revision)


Of 609 traffic fatalities in New York City in 1991 . . . 296 were pedestrians and 21 were bicyclists.

A recent transportation commissioner repeatedly decried "drunken" pedestrian fatalities, ignoring that his agency's threshold for citing pedestrian victims as alcohol-impaired was ten times below the legal criterion for intoxication of a motorist. The current commissioner calls comprehensive European-style "traffic-calming" measures premature, citing a 20% drop in pedestrian deaths of late. Yet aggressive enforcement of traffic codes and licensing laws has cut pedestrian fatalities in London by 50%, and the fatality rate in Paris and Tokyo stands at half of ours.

-- Charles Komanoff, 'Commemorating Gavin Cato', City Limits 1997 reprinted here


90% of cyclist road accidents are impacts of motor vehicles, 75% of cyclists suffering an accident were not infringing the law, about 2% of traffic fatalities in Spain are cyclists. Most cycle accidents happen on weekends, with fine weather and on broad roads, when cyclists are disrespected by motorists who overtake them at only a few centimetres or even less, simply "don't see them" or claim that the cyclists "have come over them" inadvertedly.

ConBici, Coordinadora en Defensa de la Bici
Spanish cyclist advocacy group responding to a discriminatory anti-bike law passed in Spain in 1999


Brain injuries for males between the ages of 15 and 24, the highest risk group: Daniel Convissor's bike pages

Fatalities due to head injury according to road user group, England and Wales, 1987 to 1991

All fatalities 

Fatalities from head injury 

Road user type: 

Number 

% of all 

Number 

% of all 

% of this type 

Pedestrians 

7983 

34.8 

4432 

39.1 

55.5 

Cyclists 

1344 

5.9 

958 

8.5 

71.2 

2-wheel motor riders 

3009 

13.1 

1348 

11.9 

44.8 

Vehicle drivers 

6459 

28.1 

2824 

24.9 

43.7 

Vehicle passengers 

4159 

18.1 

1761 

15.6 

42.3 

All 

22954 

100.0 

11323 

100.0 

49.3 

Source: special tabulations from the Office of Population Censuses and Surveys.
Quoted by Mayer Hillman 1993

[Editorial note: some people find this table difficult to read at first glance. Pedestrians represented almost 35% of all road fatalities. Cyclists represented less than 6%. 55% of dead pedestrians died of head injuries, as compared to numbers around 44% for motorized travellers and 71% for cyclists. But cyclists still represented only 8.5% of all road deaths from head injury, whereas pedestrians represented 39%.]


When over 50 times as many people are killed in cars or walking across the street, over 40 times as many commit suicide, over 30 times as many get murdered, over 15 times as many die from falling, over 9 times as many get poisoned, over 6 times as many die of burns, over 5 times as many drown, and over 25 times as many die of various and sundry causes, why is cycling perceived to be dangerous? . . .

[In terms of fatalities per million exposure hours] bicycling is nearly six times as safe as living! What does that mean? It means that if you were immune to all kinds of deaths except cycling accidents and you bicycled 24 hours a day, 365 days a year, that you would, on the average, live nearly six times as long as the average person!

-- Ken Kifer, 'Is Cycling Dangerous?'


None of the cyclists had worn helmets and, in order to assess the maximum possible benefit of helmet wearing, it was assumed that a helmet would have saved all those who only had head injuries. It was found that helmets might have saved 14 lives in 15 years. A similar calculation based on the controls suggests that if all pedestrians and vehicle occupants had worn helmets, 175 lives might have been saved in the same period.

-- A. Kennedy, 'Pattern of injury in fatal pedal cycle accidents and the possible benefits of cycle helmets' British Journal of Sports Medicine vol 30 no. 2 1996 abstract cited here


Cyclists are not alone in suffering head injury as a result of road crashes. From 1987 to 1991 fatalities in Britain due to head injuries were proportioned:

Car occupants 40.5%
Pedestrians 39.1%
Motorcyclists 11.9% (despite use of helmets and a lower total distance travelled than by pedal cycle)
Cyclists 8.5%
. . .

Analysis suggests that cyclists live at least 2 years, and possibly as much as 10 years, longer than non-cyclists, and cycling regularly is 20 times more likely to increase someone's life span than to shorten it (ref 38). This puts the risk of serious injury to cyclists in perspective.

It seems reasonable to expect that reductions in injuries brought about through the wearing of cycle helmets would be reflected in the general accident statistics in places where helmet use has become significant. This should particularly be the case if the more optimistic predictions for injury reduction are correct. However, whole population statistics from Australia, New Zealand, the United States and Canada show no distinguishable change in fatalities, and statistics for London show no such change for any severity of injury, as helmet use has increased substantially. This suggests that the real-world performance of cycle helmets may be falling well short of the predictions that have been made.

-- John Franklin, The Effectiveness of Cycle Helmets


. . . it is impossible to build a helmet that will offer significant impact protection.

-- Dr. George Shively, The Snell Memorial Foundation


. . . helmets will mitigate the effects of falling off your bicycle and striking your head . . . If a cyclist is accelerated by a car, then the helmet will not work and will not prevent a severe or even fatal injury.

-- Dr. Michael Schwartz, neurosurgeon and member of Canadian Standards Association Committee establishing helmet standards


One has to agree that in high speed impacts [a helmet] won't prevent death.

-- Dr. William Lucas, Toronto Coroner, September 1998


In situations of a fall they [helmets] are next to useless because they do not protect against diffused brain damage. The damage to the brain would still have occurred because it is the rattling inside the skull that caused the damage.

-- Chief Pathologist Clive Cooke,
Coroner's Court Testimony, Perth, Australia


Even though bicycle helmet use increased dramatically over the last decade, head injuries rose 10%, according to the Consumer Product Safety Commission. In fact, fewer people are now riding bicycles, which means that the rate of head injuries has actually increased by 51%.

Officials still recommend that riders wear helmets while bicycling because they dramatically reduce the severity of head injuries when accidents do occur.

A variety of factors contribute to the increase in head injuries, including a lack of safe places to ride and more aggressive and distracted drivers. In addition, many people do not understand the rules of the road when it comes to bicycling. Furthermore, experts say bicyclists feel a false sense of security when riding with their helmets, leading them to take more risks.

The Consumer Product Safety Commission is investigating this alarming trend. Bicycle industry officials say that helmets could be improved to provide more protection, but they warn that new designs may be heavier and less comfortable, which may reduce usage.

--- www.injuryboard.com (consumer advice website sponsored by US law firms)


. . . just consider the market: an accessory that is a genuine safety aid, that isn't particularly cheap and that millions of people have to buy.

-- editor of the UK retailers' trade journal Cycle Trader, Nov 1989


Speaking at the Annual State Conference of Sports Medicine Australia in Busselton at the weekend, Dr McCrory said that parents were wasting their money buying helmets to protect their children while playing football.

Testing of current commercially available football helmets shows they offer no protection at all against concusssion.

"In fact, wearing helmets can potentially lead to more severe injuries than no helmets," Dr McCrory said. "Helmets give a false sense of security and lead to greater risk taking, especially amongst younger players."

-- Sports Medicine Australia, March 8, 2000 press release


Whilst helmets may possibly reduce the incidence of scalp lacerations and other soft tissue injury, there is the risk that helmets may actually increase both the cerebral and non-cerebral injury rates. ... The addition of a helmet will increase both the size and mass of the head. This means blows that would have been glancing become more solid and thus transmit increased rotational forces to the brain and may increase diffuse brain injury.

-- The Australian National Health and Medical Research Council in a 1994 study of football helmets and head injuries
quoted in Bicycle Helmets and the Mechanics of Head Injuries by Peter van Schaik


Protective devices paid for by the individual are cheap for the authorities, but is the total amount of money spent cost-effective?

-- The European Cycling Federation safety brochure


According to the National Safety Council's Accident Prevention Manual, the product design process must adhere to the following priority list:

Priority 1: Eliminate the hazard through design.

Priority 2: Neutralize the hazard with fixed guards, automatic-stop devices, or other protective safety devices.

Priority 3: Provide warnings when the hazard cannot be designed away or neutralized by guards.

Priority 4: Develop and implement operation procedures and employee training programs to modify product users' behavior.

Priority 5: Provide product users with protective equipment and clothing.

-- NSC manual quoted at Ryan Engineering page

[Editorial note: making users wear protective gear is the solution of last resort to safety problems, according to the NSC.]


Research by the European Cycling Federation found that non-cyclists tended to be most in favour of helmets . . .
The board's previous reports have concluded that the benefit to health of regular exercise from cycling outweighs the British cyclist's comparatively high risk of trauma. In countries such as the Netherlands and Denmark pedestrians and cyclists form a much smaller proportion of those injured or killed on the road, though helmets are little used. Instead, these countries have concentrated on safety programmes to reduce motor traffic speeds to 30 km/h in urban areas and separate cyclists from fast moving traffic.

-- Douglas Carnall reports the findings of the British Medical Association's Board of Education and Science report in the British Medical Journal June 1999
[italics mine :-) --d.c.]


In the Newcastle study, five times as many child pedestrians died of road accidents as child cyclists. Convinced helmeteers should recommend all children playing or travelling in the streets to wear helmets (presumably heavy motor-cycle helmets).

-- M. McCarthy, 'Children and Cycle Helmets',Child Care Health Developments, London UK 1996


As a matter of fact, though bicycles outnumber cars globally by a ratio of 2 to 1, only two percent of the world's traffic fatalities involve cyclists. When bikes and cars are given each their own space, the risk of death is 500 times greater in cars.

-- Ed Ayres, Worldwatch Institute, quoted in 'Don't Kill the Goose that Lays the Golden Egg' by Thomas deMarco


WA's helmet legislation has diverted resources from preventing bicycle crashes into increasing helmet wearing rates. For instance, about 50% of the WA Police Bicycle Safety Section's time is devoted to enforcing the helmet law. At the same time, about 80% of cyclists on the road at night are riding without lights, with very little chance of getting apprehended. There is a very strong case that enforcement should be directed to crash prevention measures.

-- Bruce Robinson, 'Is there any Reliable Evidence that Australian Helmet Legislation Works?' Bicycle Federation of Australia, Velo Australis Proceedings 1996


When helmets were made compulsory in Australia, admissions from head injury fell by 15-20%, but the level of cycling fell by 35%. Ten years later, cycling levels in western Australia are still 5-20% below the level they were before the introduction of the law, yet head injuries are only 11% lower than would be expected without helmets. Incidentally, 17 times more motorists than cyclists died of head injuries in Australia during 1988.

-- Malcom Wardlaw, op. cit.


[Editor's note: we keep hearing how many vehicle occupants die of head injury. Maybe we should be putting the helmets on the car drivers and passengers?]
Recent media reports on helmet-wearing for motor vehicle occupants brings to the public attention an issue that many would rather not hear about... a report by the Federal Office of Road Safety ... saying there would be huge savings if motor vehicle occupants wore helmets.

... FORS has broken ranks with the rest of the helmet-promoting community and in doing so has endangered a situation that others have taken years to produce. When promoting helmets you must never mention motor vehicles.

... The head injury risk per hour is about the same for motoring and cycling; there are many more driving hours than cycling ones. Driving offers no health benefits, unlike cycling; on average healthcare costs for victims of motor vehicle accidents are higher than those for cycle accident victims.

... promoting helmets for motorists will meet heavy opposition from the motoring lobby. But that same lobby will back helmets for other activities, in particular the potential victims of motorists.

Helmets for Cars Would Save Lives
Newspaper article by Nigel Perry, The Dominion newspaper, NZ 1998


In 1996, the City Council [of Austin TX] passed a wildly unpopular all-ages bicycle helmet law. (Passed 5-9-96, cops started enforcing on 8-18-96). As a result of public outcry, in the summer of 1997, the City Council modified the helmet law so that it applies only to minors (17 and under) . . .

. . . Predictably, following passage of the original helmet law, cyclists were jailed left and right (yes, many were arrested, not just ticketed). The League of Bicycle Voters circulated a petition get the City Council to repeal the ordinance, and other cyclists tried to have the ordinance declared unconstitutional in court. In the meantime, the City Council changed the ordinance to apply to minors only, but would not repeal the ordinance outright. The minors-only provision is still a problem. Before the council made the helmet law kids-only, 70% of no-helmet tickets given to kids were given to black & Hispanic kids. After the helmet law was made kids-only, to date (1-99) that figure has jumped to 92%.

In the past 16 years preceding the ordinance, the City hadn't done squat to make it safer to cycle (vs. safer to crash). It's just common sense that real bicycle safety would involve efforts to keep us from getting hit in the first place, rather than to keep City streets dangerous for cycling and then think that making us strap helmets on makes everything fine. For example, it's legal for cars to park in most bike lanes in Austin, and no real money had been spent on improvements for cycling in at least 16 years. Trying to force us to wear "safety" equipment when the City itself is responsible for unsafe cycling conditions is an incredible insult . . .

The helmet ordinance criminalizes the act of cycling. This is just another excuse for the police to abuse us. Cyclists were arrested (not just ticketed) and roughed up for not having helmets. By contrast, has anyone ever heard of a motorist going to jail for not wearing a seat belt?

With the helmet law, it was easier to go to jail for biking without a helmet than for running over and killing a cyclist with your car. The law would also make it nearly impossible for cyclists or families to collect from a motorist in a collision in which the cyclist wasn't wearing a helmet, even if it was the motorist's fault.

-- Michael Bluejay, Austin TX bike activist


The number of Australians whose lives have been "saved by helmets" [according to anecdotal accounts in the media] over the past decade is staggering. I estimate that here in Western Australia the helmet law has saved about 5,000 lives per year... based upon the claims by cyclists who wouldn't know what to do without a helmet law.

It's curious that the average annual cyclist death toll in Western Australia before law enforcement was just 7. If the anecdotal claims are to be believed, it might be surmised that the wearing of helmets has caused an average 4,993 cyclists to have a near-fatal accident per year!

-- Chris Gillham (Australian activist working to repeal all-ages MHL)


In signing this agreement I acknowledge that bicycling is inherently dangerous . . .

-- Legal language on a bike loan agreement in California, USA


"You should wear a helmet. If you wore a helmet, I wouldn't NEED to drive more safely."

--Driver to cyclist, after being told to "drive more safely"