I will make two points on this discussion.
1. Road deaths have been dropping ever since records started, and are now well below other causes of death, including suicide. This does not match the statements above about how bad driving is. Certainly it is not perfect, but in most cases it is adequate. In my view the only changes that have had a major impact on road fatalities have been seat belts and random breath testing. Most of the rest of the improvement has been from improved road conditions and driver attitude.
2. One of the advantages of random breath testing is that it gives a direct measure of what proportion of drivers are intoxicated. This figure, for recent campaigns, is always well below 1%, often a long way below. All drivers involved in fatalities are tested for blood alcohol (post mortem if necessary). Recent figures run from 20 to 30% above the limit. This data does not support speed as being a primary cause of accidents - draw your own conclusions. Of course this leaves teh cause of the other 70-80% unclear, but considering that many of the fatal accidents involve two or more drivers, and only one may be intoxicated, add in the undetected drug affected drivers, and subtract the deaths that are really suicide, and it is, to me, fairly clear that substance abuse is far more important than speed.
I would also caution that any accident will not have a single, or even necessarily a major, cause. See references to the "swiss cheese model".
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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