The statistics I’ve seen make alcohol clearly the leading cause of fatal car accidents.
But any time alcohol is involved in a fatal car accident, it will be identified as ‘the cause’, regardless of whether the accident would have happened anyway, or would not have happened if some other factor had been fixed.
If it were the case that drunk driving was fairly common and it was only slightly correlated with higher incidence of accidents, I would still expect folks to blame accidents where the driver was drunk on the alcohol.
You’re right, I was careless in speaking of “cause” when I really mean “present in a larger proportion of fatal car accidents than any other measured risk factor”.
an estimated 2.8% of drivers exceed the legal consumption, 5.8% when it comes to drivers involved in an accident causing death or injury and 16.5% for drivers involved in fatal accidents.
This relies on a method for estimating the “base rate” which isn’t disclosed, but if correct this seems on its face to support the causal inference. By comparison, from the same study,
drowsiness or exhaustion are factors in 2.8% of fatal accidents.
This is a report by professional accidentologists, and in France at least there is serious pressure on everyone involved to do a thorough job of analysis and reporting. Every single accident involving physical injury (severe enough for police to be involved) is reported in detail by the police on the scene on a standardized form which is then filed for central aggregation.
Reduction of driving related fatalities has been a major political objective in the past few years—moreover, one that is showing actual results. There are few enough instances of such efforts bearing fruit that this exception is worth noting. So, at present I have no particular reason to believe that sleep-deprived driving is “more dangerous” than drunk driving and that the focus on the latter reflects anything other than an appropriate evaluation of the relative safety gains.
I might change my mind if I came across a specific critique of the methodology used to collect accident data and likely causal factors.
I do wonder if ‘sleep-deprived’ is even suspected / reported in someone who is also drunk. I would imagine that a lot of drunk drivers are also sleepy, and I’m not sure you’d notice the symptoms of sleepiness and not attribute that to the alcohol.
You’d have to look closer at the statistics, I suspect that the clustering of fatalities would give a fairly clear picture: for instance, an altogether too frequent type of DUI fatality is young adults driving home from a night out, dancing and drinking, in the wee hours of the morning. Obviously fatigue is a factor on top of alcohol, but it’s not clear that anything would be gained by counting those as “sleep deprivation related accidents”.
I suspect that a kind of Pareto analysis is what’s really called for in limiting the costs of traffic accident; you want to target, not generic causes (e.g. speeding or drunk driving or fatigue) but specific clusters of behaviours that account for disproportionate numbers of accidents. If you can stamp out driving-home-drunk-and-tired-from-nights-out behaviours, you’re already reducing the total fatality count by a lot. (This is precisely how traffic safety campaigns have been organized lately here.)
But any time alcohol is involved in a fatal car accident, it will be identified as ‘the cause’, regardless of whether the accident would have happened anyway, or would not have happened if some other factor had been fixed.
If it were the case that drunk driving was fairly common and it was only slightly correlated with higher incidence of accidents, I would still expect folks to blame accidents where the driver was drunk on the alcohol.
You’re right, I was careless in speaking of “cause” when I really mean “present in a larger proportion of fatal car accidents than any other measured risk factor”.
In my neck of the woods,
This relies on a method for estimating the “base rate” which isn’t disclosed, but if correct this seems on its face to support the causal inference. By comparison, from the same study,
This is a report by professional accidentologists, and in France at least there is serious pressure on everyone involved to do a thorough job of analysis and reporting. Every single accident involving physical injury (severe enough for police to be involved) is reported in detail by the police on the scene on a standardized form which is then filed for central aggregation.
Reduction of driving related fatalities has been a major political objective in the past few years—moreover, one that is showing actual results. There are few enough instances of such efforts bearing fruit that this exception is worth noting. So, at present I have no particular reason to believe that sleep-deprived driving is “more dangerous” than drunk driving and that the focus on the latter reflects anything other than an appropriate evaluation of the relative safety gains.
I might change my mind if I came across a specific critique of the methodology used to collect accident data and likely causal factors.
I do wonder if ‘sleep-deprived’ is even suspected / reported in someone who is also drunk. I would imagine that a lot of drunk drivers are also sleepy, and I’m not sure you’d notice the symptoms of sleepiness and not attribute that to the alcohol.
You’d have to look closer at the statistics, I suspect that the clustering of fatalities would give a fairly clear picture: for instance, an altogether too frequent type of DUI fatality is young adults driving home from a night out, dancing and drinking, in the wee hours of the morning. Obviously fatigue is a factor on top of alcohol, but it’s not clear that anything would be gained by counting those as “sleep deprivation related accidents”.
I suspect that a kind of Pareto analysis is what’s really called for in limiting the costs of traffic accident; you want to target, not generic causes (e.g. speeding or drunk driving or fatigue) but specific clusters of behaviours that account for disproportionate numbers of accidents. If you can stamp out driving-home-drunk-and-tired-from-nights-out behaviours, you’re already reducing the total fatality count by a lot. (This is precisely how traffic safety campaigns have been organized lately here.)