2009-05-21-12:06:08

Vehicle Safety



I've been involved in an ongoing disagreement on a mailing list (which will go unnamed to protect the innocent) about motorcycle safety. The overwhelming majority (all the non-lurkers, it seems) on the list seems to believe that no single motorcycle (type) is safer than any other (type). And the primary justification for this position is that the majority of motorcycle crashes seem to be a result of rider error. I.e. there are no (or very weak) correlations of the crashes to any other factor.

Of course, being the obstinate, ignorant, bull-headed, contrarian that I am, I disagree with this position. And, it's useful to add that many of the people on that mailing list are motorcycle instructors... making me not just obstinate, ignorant, bull-headed, and contrarian, but also an anti-authoritarian dissenter. :-)

Now, practically, a large source of my objection to their justification is that we (being the parts of US society with which I'm familiar) seem to have accepted the fact that other vehicles like cars, trucks, trains, ships, and planes can be categorized according to how safe they are. The primary critical question that keeps me skeptical of their justification is: Why would motorcycles be so fundamentally different from other vehicles? Why do all other vehicles submit to a safety gradation but motorcycles do not?

Now, of course, in most instances of heavy impact crashes like those involving trains, ships, and planes, the putative cause is some form of "pilot error". And that fact may seem to bolster the justification that motorcycles don't submit to a safety gradation. Further, the commonality of the ascription of "pilot error" to these high profile crashes might be justification for thinking that the safety gradation we apply to trains, ships, and planes is unwarranted or just plain false! Perhaps no one (type of) train, plane, or ship is any safer than any other (type of) train, plane, or ship!?!? Indeed, if most of the crashes are the result of "pilot error", then the relative safety of one vehicle over another may well be buried down in the noise of the data.

However, I don't think that's the case. The fact that most of these high-profile crashes are putatively the result of "pilot error", weakens the justification for the belief that no one (type of) motorcycle is safer than any other (type of) motorcycle. It weakens it because we can ask: Well, if even in these crashes involving other types of vehicle (trains, planes, and ships), the putative fault lies with the "pilot" but we maintain that some of these vehicles are safer than others, then we can do likewise with motorcycles.

At least, from a skeptical point of view, it's reasonable to claim that all vehicles are similar in their submission to a gradation of safety. I.e. either motorcycles submit like all the other vehicles, or NONE of them are more or less safe.

And since the general consensus seems to be that all other (non-motorcycle) vehicles submit to a safety gradation, then so do motorcycles. I.e. some (types of) motorcycles are safer than others.

So, why would all these relatively intelligent, knowlegable people deny that reasonable, consensus based position? The answer is that there is not enough data to say one way or the other (despite their insistence that there is enough data to demonstrate that rider error is so totally dominant that other correlations are lost in the noise). Very few scientific motorcycle safety studies have been done. The authoritative one (the so-called "Hurt report") took place between 1976 and 1981. And traffic patterns, technology, and human density has changed quite a bit since then.

However, the paucity of data is not quite sufficient to explain why seemingly intelligent and knowlegable people would reject the reasonability of the conjecture that motorcycles are just like any other type of vehicle (and hence submit to a safety gradation). The lack of data is necessary but not sufficient to explain their zealous attachment to the uniqueness of motorcycles as a type of vehicle.

I posit that the additional condition that we need to add to build a sufficient explanation for their zealotry is two-fold: 1) conservatism: don't change what ain't broke and 2) liberalism: don't limit freedoms unless you can demonstrate the benefits and costs of such limitations.

In other words, these people don't want the gub'ment to willy-nilly, without good reason, to slap any type of restriction on the manufacture and use of motorcycles. And that strikes me as reasonable, as well. If yahoos like me start yapping loudly about how motorcycles are just like any other vehicle and some are safer than others, then we might see more junk science (in the form of actuarial assessments) arguing that, for example, "super sport" motorcycles should be banned. And no matter how rational the yahoos like me may actually be, those rational arguments will be co-opted and abused by cranks who feel they need to do something and, subsequently, will jump to ANY premature conclusion that presents itself.

Having said all that, the ethical dilemma I face is: Do I allow the fear of premature conclusions to prevent me from discussing motorcycle safety in a rational way? Obviously, as evinced by this web log post, I don't cower in the face of such fears. As with the fear that the gub'ment might ban some sorts of guns, we cannot allow our fears coerce us into zealous over-commitment to false ideology.

The reality is that some (types of) motorcycles are safer than others. And we desperately need more data to determine that safety gradation, which is why this news is so bad.