Genesis of the 'speed kills' paradigm

In this and future comment pieces, I would like to discuss the true cause of, and possible cures for, roadway collisions.

To begin that discussion, it is worth looking back in time to discover why politicians around the world have been misled into promoting the ‘speed kills’ theory of traffic safety.

An excellent summary of the genesis of that ‘political emphasis’ on speed limits is provided by Stephen Godwin, of the US Transportation Research Board*.

“… the first speed regulations predate the invention of the automobile by over 200 years. The town of Newport, Rhode Island attempted to prevent the deaths of pedestrians by prohibiting the galloping of horses on major thoroughfares… In 1901, shortly after the advent of automobiles, the State of Connecticut set the first maximum speed limit in the US at…8mph … These policies were typical of the earliest approaches to speed limits. Local officials posted maximum limits to protect pedestrians rather than to benefit vehicular traffic flow.

“… By 1930, millions of motorists were driving cars capable of traveling at 80 to 100 mph when the maximum speed limit posted in most rural areas was about 40 mph …Traffic engineers, however, appeared to share the opinion that speed limits were ineffective. According to a University of Illinois study done in 1948, motorists drove at speeds they believed reasonable, regardless of the posted speed, and most maximum limits were considered below those deemed reasonable by motorists (The American City 1950).

“…During the 1950’s traffic engineers began advocating an approach to speed limits that accommodated the preferred driving speeds of the public. … the 85th percentile method [setting the speed limit at 85% of the established traffic flow] became the most popular method for setting speed limits, and by 1970 was by far the most frequently used method by cities and states …

“The 55 mph National Maximum Speed Limit was established by Congress during the energy crisis of 1973 … The fatality rate on rural Interstates declined by 34% … Because of this remarkable reduction in fatalities, the largest annual decline since World War Two, Congress made the temporary energy policy a permanent safety policy.”

This US experience is typical of other countries. Most countries in (then Western) Europe also reacted to the oil crisis by imposing speed limits on their motorways in ‘73 and were astonished when ‘74 brought the largest one-year reduction in the fatality rate (per kilometre traveled) they had ever seen.

Unfortunately they failed to notice that at least two countries, Germany and Italy, did not introduce speed limits on their motorways in ‘74, but saw the same huge reduction in their fatality rate. As any scientist will tell you the huge reductions in expressway fatality rates, which occurred in all European countries in ‘73/74, could not possibly have been caused by the speed limits imposed in only some countries.

At the next opportunity I will discuss the truly tragic coincidence, which explains what really happened in ‘73/’74.


(*Stephen R. Godwin, Implications of raising the US maximum speed limit to 65mph, Proceedings of Roads and Traffic Safety on two Continents VTI rapport 332A Väg–och Trafik Instituet, Linköping, Sweden, 1988)

It is not about speed, but speed differential. The safest way to drive is “go with the flow”, regardless of the speed limit. Slow moving vehicles may cause as many problems as the fast ones. Slow moving vehicles back up traffic, break uniformity of flow, and generate unnecessary gaps that get filled in by passing vehicles. So flow becomes more turbulent.

Passing and lane changing manoeuvers create much higher potential for accidents. Besides, drivers following slow moving vehicles and attempting to pass them become more aggressive. The longer you follow the “slow guy”, the more aggressive you get. This aggressiveness may remain for the rest of the trip. A driver who was following the flow all of a sudden becomes a speeder.

Alex Mirsakov, New York, USA - HSA Software Support

From my point of view the "speed kills" paradigm has some validity by sheer logic. It\'s obvious that for any traffic situation there is a limit in speed above which it is unsafe to go. And there is a propensity for motorists to drive as fast as possible.

Speed alone may not kill, but it certainly aggravates the consequences of mistakes and of bad luck, just as obesity and unhealthy lifestyles raise the risk for numerous diseases.

Reiner Dölger, Mainz, Germany

I believe the reduction in automotive fatalities in the West has been due to a combination of more seat belt use, more stringent drunk-driving enforcement, the advent of vehicle airbags, more energy-absorbent automobile bumper and door designs, and most importantly, much better handling and performing automobiles that can get out of their own way under emergency driving conditions.

In at least one part of the world, notably the Middle East /Gulf region, the fatality rates are climbing – due to a lethal combination of increasing traffic volumes and a broad vehicle and population demographic, which consists of the fortunate people in the Mercedes and Lamborghinis (who often want to demonstrate how fortunate they are in front of everyone else), and less fortunate people in overcrowded Nissan Sunny sedans, old buses, and underpowered, undersized trucks with wheezing engines, all mixing onto the same roads.

The answer is that, yes, speed kills – if the driver is an idiot.  Prevailing speeds are what they are, and trying to go 120 mph when everyone else is going 60 mph or less (unless you are wearing the appropriate uniform and have the flashing blue and red lights on your roof and a really loud siren) is ludicrous.

Glenn Havinoviski, Reston, Virginia, USA