«

»

Sep
30
2009

Second open letter to Executive Director of PACTS

To Robert Gifford

Executive Director, The Parliamentary Advisory Council for Transport Safety

Dear Rob

I’m sorry but I must persist. The power and endurance of the myth that PACTS and RoSPA have built around the seat belt law takes a lot of deconstructing. So long as belief in the efficacy of the law persists it will continue to serve as one of the principal arguments of the campaigners for compulsory cycle helmets.

Seat belts and helmets are routinely linked. Injury lawyers argue helmetless injured cyclists risk having their compensation reduced for contributory negligence in the same way that unbelted motorists would. (see also here) Earlier this year the Mississippi Senate threw out a bill to repeal the State’s mandatory cycle helmet law on the grounds that “the helmet requirement was similar to the state’s seat belt law, designed to protect people from avoidable injuries.”

You say in response to my earlier letter “While I entirely accept that the piece on our website referring to the estimate of 50,000 lives [60000 actually] could have been more appropriately worded, I cannot share the view that seat belts have not been an effective contribution to casualty reduction.”

Short of a complete public retraction I cannot imagine an “appropriate” way to refer to the 60000 claim. The claim that the seat belt law has saved 60000 lives is ludicrous. I accept that the number was not your invention, but so long as it remains on your website, it strongly implies to the reader that PACTS considers the claim to be valid.

I ask you to re-read this passage on your website:

“On the 31st January 2008, the 25th anniversary of the law change which made front seatbelt wearing compulsory was celebrated. PACTS itself was set up by Barry Sheerman MP as part of the fight to get mandatory seatbelt wearing turned into legislation. Eight years later it became compulsory for all backseat passengers to use seatbelts and it is estimated that since the introduction of the first law change in 1983, seatbelts have prevented 60,000 deaths and over 670,000 serious injuries.”

As most parliamentarians, and the rest of the world, will read it, PACTS is celebrating its role in saving 60000 lives. Indeed this piece of self congratulation identifies the seat belt law as the foundation stone of your organization.

In your article five months later in Significance (June 2008, sadly available free only to those with institutional access to electronic journals) you concluded that in the first year of the law it had saved not 2400 lives but 164 net. Here (for those without access to electronic journals) is Table 1 from your article.

picture-14

In your article from which this table is taken you say: “The best estimates … are that extra deaths to vulnerable road users did accompany the introduction of mandatory wearing of seat belts.”

In your response to my article advocating repeal of the seat belt law you do not comment on my point that most of the decrease in car driver deaths in 1983 consisted of drivers who were over the alcohol limit (down 14%), and that this coincided with the introduction of evidential breath testing. Do you think that this change in the law with respect to drinking and driving had no effect?

In your Significance article you are clear that you believe the law has saved the lives of people in cars at the expense of vulnerable road users: “The picture shows a clear reduction in death and injury to car occupants, appreciably offset by extra deaths among pedestrians and cyclists.”

You then proceed to defend the law as follows: “It would … be a severe constraint on the use of safety measures if any measure were to be ruled out for which the larger number of deaths and injuries saved were differently distributed among road user groups from the smaller number resulting from the measure … The wearing of seat belts is therefore not exceptional among safety measures in that extra deaths and injuries that may arise from wearing occur in part (only in part because, if wearers drive more riskily, some of the extra deaths and injuries will occur to vehicle occupants) to different road user groups than those among which deaths and injuries are prevented—though the difference is perhaps sharper for belt wearing than for many other measures.”

I take this passage to mean that you think a measure that saves the lives of motorists is OK so long as the number of vulnerable road users killed as a result is smaller.

In the light of that argument I would welcome your comment on this analogy: an Organ Harvester Lottery in which healthy people will be selected at random to “donate” organs to people in need of them. One heart and one liver could save two lives at the cost of one – slightly better than the ratio that you argue justifies keeping the seat belt law. Throw in two kidneys and you get a four to one ratio of lives saved to lives lost. This is a gruesome but not wholly inappropriate analogy given the myth circulating at the time - (and still) that the success of the seat law was responsible for increasing the shortage of donor organs.

I do hope that you will take the trouble to comment on my website. Now that the campaigners for compulsory cycle helmets are on the march again that part of their “evidence” invoking the “success” of the seat belt law needs renewed scrutiny.

Best wishes

John

4 comments

No ping yet

  1. Dr. Robert Davis says:

    Thee seat belt law experience is highly relevant today in ways relevant to matters othjer than cycle helmets: however much eyes may roll at the prospect of statistical analysis of a law passed decades ago, this matter is highly pertinent.

    Firstly, the obvious truth of adaptive behaviour or risk compensation is central to contemporary discussions of some very positive episodes: the good experience of safety with “shared streets” and the decline in casualty rates among London cyclists as just one example of “safety in numbers” with numbers of cyclists approaching “critical mass”.

    Secondly, the obvious truth of adaptive behaviour or risk compensation indicates that the relentless idiot-proofing of the driver environment – whether of the vehicle or highway – has produced idiots in such a way that the “road safety” lobby is hardly well qualified to pontificate on matters of cyclist or pedestrian safety – of which cycle helmets is just one. No doubt this is a main reason for the denial of such effects from the “road safety” establishment.

    Thirdly, the obvious truth of adaptive behaviour or risk compensation indicates that supposed progress in declining RTA fatalities and other casualties may have resulted from adaptive behaviour by the most benign and vulnerable road users ,as opposed to “road safety” interventions, including migration from the road environment entirely. Again, this might explain some denial from practitioners of “road safety”.

    Finally, the obvious truth of adaptive behaviour or risk compensation indicates that some changes in fatalities are due to changes described by the Smeed and Adams curves, and are independent of interventions claimed by “road safety” professionals.

    All of this suggests that denial on their part is understandable, but not acceptable to those of us concerned with the safety of all road users and the truth.

  2. Dr. Robert Davis says:

    Can I make another comment which seems rather crucial?

    You say:
    ” In your Significance article you are clear that the law has saved the lives of people in cars at the expense of vulnerable road users: “The picture shows a clear reduction in death and injury to car occupants, APPRECIABLY OFFSET BY EXTRA DEATHS AMONG PEDESTRAINS AND CYCLISTS.”(MY EMPHASIS – Rob Giffords words).

    John , you then go on to give a (blackly) amusing analogy. One can put this in a less dramatic way: doctors – and doctors are among the main proponents of such types of intervention – are required by their ethical code (the Hippocratic Oath) to “First, do no harm”. You appear to admit that this is precisely what they have not done – that they have killed people in the most vulnerable, and least dangerous to others, road user groups in the name of “road safety”.

    For this reason those of us who are supporting the most benign and healthy forms of transport are unlikely to trust PACTS, RoSPA and others supposedly concerned with safety on the road ,of which bicycle crash helmets are just one issue.

    If Gifford values his reputation among those concerned with the safety of all road user groups and the genuinely scientific community, I suggest he reconsiders as John suggests.

  3. Malcolm Wardlaw says:

    Dear Professor Adams,

    On a point of detail, the “cycle helmet law” you refer to is actually for motorcycle helmets. There are no all-ages cycle helmet laws in the US. 22 states have child cyclist helmet laws, but few, if any, are enforced in any significant degree. For instance, in California there is such a law, but this does not prevent Miley Cyrus and friends riding their cruiser bikes around without helmets. Fortunately the LAPD recognise a waste of time when they see it.

    I should have thought the greatest mileage in criticising seatbelt laws (as a mistake not to be repeated) would be to focus on deaths to cyclists and pedestrians. The result above shows 38 extra cyclist deaths in 1983, a year in which there were 323 reported cyclist deaths. That would mean that about 1 in 8 cyclist deaths that year were due to the seat belt law. That is quite an awesome conclusion, in terms of the injustice and cynicism of a state that imposed such extra risk on those pursuing a harmless, healthy activity – especially now that there is so much push today to get mnore people cycling.

    There is also a lesson to those opposing cycle helmet laws. There is nothing that law campaigners will not stoop to to get their way. Take a look at my response to a paper published in Pediatrics last year:

    http://pediatrics.aappublications.org/cgi/eletters/122/3/605

    Draw your own conclusions as to the honesty of the authors of that paper. Despite this, the paper got quite wide publicity. So spreads myth in an open society.

    A big difference between seatbelt laws and cycle helmets is that credible evidence exists from car wreck analysis that seatbelts confer life-saving benefit, at least at speeds below about 50mph. Whereas, no such credible evidence has ever been forthcoming about cycle helmets. The most detailed studies show no reduction in serious injury either in collisions or in falls. The data were reported to show otherwise, because the authors were well aware that acceptable conclusions had to be provided. They were, however, honest enough to admit in the text, by the by, that their conclusions rest on quirks of the data, rather than any helmet effect.

    For me, the real giveaway is that no study has ever appeared showing effectiveness based on damage to helmets in real crashes. This is becaise researchers who have gathered helmets have failed to find any that showed crushing of the liner. Rather, the helmets just broke apart.

    Malcolm
    Many thanks for the correction about the Mississippi helmet law. Whether the law refers to bicycle helmets or motorcycle helmets the point still stands; see my article “Public Safety Legislation and the Risk Compensation Hypothesis: The example of Motorcycle Helmet Legislation”
    Thanks also for calling my attention to your excellent letter in Pediatrics. It is a devastating critique of an article calling for compulsion. Characteristically there has been no reply. Campaigners just keep campaigning.
    Another superb source of information on the subject – the most comprehensive I know – is Guy Chapman’s Cycle Helmet Portal.
    JA

  4. Robert Gifford says:

    From Robert Gifford, Executive Director of PACTS
    Dear John
    While you are perfectly entitled to criticise others for what you term “inflation” in claims of lives saved, I am sorry that you have also overlooked the other statistical analysis from the article in “Significance” [June 2008]. This referred to the report by Jeremy Broughton (TRRL Research Report 266) “Trends in drink/driving revealed by recent road accident data”. This report attempted to disaggregate the effects of the three policies and concluded that 372 fewer deaths had been achieved through seatbelt wearing, 65 from new drink/drive regulations and 54 from changes to motorcycling. It also acknowledged the increase in pedestrian deaths while observing that there was a problem with statistical significance with all the pedestrian data.
    Best wishes
    Rob

    Rob,
    You have overlooked the fact that I did not overlook the work of Jeremy Broughton. In my first Significance article (June 2007) I did comment on the work of Broughton (with Stark). Please see Figure 6. I went on to note “no studies have been done so far [by Broughton or anyone else] to explain why, after the seat belt law came into effect in Britain, seat belts were so extraordinarily selective in saving the lives only of those who were over the alcohol limit and driving between 10 at night and 4 in the morning.“ Please look again at Figure 6 and the graphs in my earlier post; can you explain why seat belts were so extraordinarily selective in saving, almost exclusively, the lives of drivers who had alcohol in their blood, and driving between 10 at night and 4 in the morning? JA

    PS “What I term ‘inflation’.” Do you still think that the seat belt law has saved 2400 lives per year? Or 372? Or 164?

    PPS In your Significance article you say “They [seat belts] prevent many more deaths and injuries than they may cause.” Is it your view that it is OK to save the lives of motorists at the expense of those of pedestrians and cyclists so long as the former are more numerous than the latter?

Leave a Reply

Your email address will not be published.

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>