Should US national speed limits revert back to 55 miles per hour?

No

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by Dick Stewart

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In the USA we know we have to accept some restrictions on our freedom to promote the overall good. Generally these restrictions are limited to actions that impinge on others' freedoms, or on their safety. There is a fuzzy line, however, between genuine public concern and the temptation among some to impose on others a restriction "for the good of us all" that is founded in Puritan morality. Federal Prohibition is the foremost example.

This Puritan impulse to force others to do "what's good for them" is also at the root of proposals to impose a Federal 55 mile per hour speed limit. It is founded in the objection to driving fast as a stimulating, even fun activity. God forbid that we should enjoy driving!

The plain Newtonian fact that under ideal conditions the power required to maintain a higher steady speed requires more fuel per mile also offends the Puritan sensibility, but is an easier reason to defend when arguing for imposition of the proposed limit.

It is no coincidence that the sponsor of this proposal is Senator John Warner of Virginia, a state with beautiful scenery and winding country roads, where a leisurely drive through rolling countryside will not cost you much in elapsed travel time. He needs to make the 500 mile drive from Reno, Nevada to Fillmore, Utah on US Route 50, "The Loneliest Road in America." Then he would understand the folly of such a ridiculous restriction.

This is no conspiracy aimed at the elimination of all speed restrictions. Sensible limits, imposed to promote safety where higher speed would constitute a public danger, are necessary. For instance, children's behavior is unpredictable, and the extra margin allowed for a quick stop makes a low speed limit reasonable in school zones.

Open highways are a different story though. Our interstate highway system was designed to be safe at speeds beyond 55 mph at a time when cars had narrow, bias-ply tires, mushy suspensions, primitive steering and suspensions overtaxed by the slightest undulation or curve in the road, and drum brakes that could barely stop them. When I rode my Honda Super Hawk across the country in 1966 the speed limit in Kansas was 85 mph, and in Nevada it was defined as "reasonable and proper." In today's vehicles, those highways are as safe for our poorly-trained drivers as we can make them, at the speeds they actually drive.

Historically, there have been three criteria for setting highway speed limits: safety, fuel savings, and revenue. The last must only be imposed with full disclosure of intent, recognized as a tax and nothing more. Speed limits imposed for the other two reasons must be based on rational and defensible arguments, not ideological reasons.

A 55 mph speed limit, with the goal of fuel savings, just doesn't work though. They tried it in 1974, and it was the most universally ignored law in US history. It's an even less viable idea today. I recently drove the approximately 250 mile stretch of Interstate 5 between the Grapevine north of Los Angeles, and the Sacramento cutoff, setting my cruise control at the speed limit. I passed not one single passenger vehicle. Every one sailed by me as though I was a moving traffic pylon. And that was where the speed limit is 70 mph and regular gas was selling in the $4.00 a gallon range.

Collateral safety effects claimed by advocates of the 1974 law were eventually disproved as statistical variations. Traffic engineers state that the most important factor in most highway accidents is not absolute speed but relative speed. If we were a nation of automatons, acting in lock step with our fellows like in some science fiction dystopia, a lower speed limit would work perfectly. We would all travel at exactly the same speed and no one would ever rear-end anyone else. But we are not robots.

In fact we are independent, often irrational humans. Look at that trip I mentioned. We overwhelmingly support the idea of speed limits, and then almost universally ignore them. Why? Because every one of us is absolutely convinced that he or she is capable of driving safely above the legal limit, whereas everyone else on the highway was granted a license to drive only because testing is too lax, and we need speed limits so that we have a legal basis to arrest those incompetents when they drive beyond their ability.

A maximum national speed limit might almost work if it was set at what traffic engineers will tell you is the safest speed. It would not be uniform, but set at the speed under which 85% of people would drive on that particular section of road if there were no speed limit. That would minimize that dangerous speed differential between cars.

Any other method is just pulling a number out of the air. Any one you picked would be as good a speed limit as the next. Why 55? Why not 57? Or 48? No, the last time we tried it we proved it doesn't work. We'd end up with most people ignoring it again, while a few would crawl along, clogging traffic, and making life miserable and less safe for the rest of us.

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