Speed Limit Rhetoric Plays Fast and Loose with Facts

January 01, 1996  ·  Michael Fumento  ·  Airbags

It’s "a death sentence for a lot of Americans on the highways." That’s how Joan Claybrook, president of the Naderite group Public Citizen, characterized the Senate voted to end the national speed limit for cars and let the states again choose their speeds. The White House has joined the cry, as has Transportation Secretary Federico Pena who estimates eliminating the national speed limit will cost an additional 5,000 lives a year. It does seem intuitive that higher speed limits means more deaths. After all, the faster the speed at which two objects collide, the harder the impact and the more things go snap, crackle, and pop. It’s also true that the faster you’re going when you hit the brakes, the longer it takes to stop.

The problem with applying these two physical laws and coming up with 4,000 more traffic deaths annually is that people are not simple crash dummies - though to look at the decline in SAT scores that may not be true for long.

For one thing, people forced to drive slowly may be less alert and aware than they would be at higher speeds. Speaking from experience, one drives with amazing alertness on the German autobahn when keeping up with most of the traffic at 100 miles an hour and yet regularly forced to move aside by cars blinking their headlights because they want to pass at 150. Still, low-speed proponents claim they have figures to prove their case. They say, for example, that death rate on the nation’s roads declined dramatically after the federal speed limit was imposed in 1974. Yes, but death rates have always been declining.

In 1925, 35 Americans died per hundred million miles driven. By the first full year of the 55-mile-per-hour national speed limit that was 3.45. Today it is less than two, even though the great majority of states have pushed their limits up to 65. There are many reasons for this decline, but mainly it’s because cars and roads just keeping getting safer.

Only in 1991, three years after states began pushing their limits back to 65, did the fatalities-per-miles driven rate inch up, only to fall again the next year. Preliminary data shows that 1994 will probably have fewer deaths per mile than any year in history.

National speed limit proponents also note that almost one-third of highway fatalities are "attributed to" speeding. But this means little. If a driver is rip-roaring drunk, swerves all over the highway, and then finally has an accident while doing 75, this gets categorized as "attributed to speeding." Reckless drivers and drunks tend to have accidents and to speed, so it all gets wrapped together. Finally there is an oft-cited study showing that after some states increased their limits from 55 to 65, accident deaths went up on those roads.

But another study commissioned by the American Automobile Association Foundation for Traffic Safety showed that looking statewide, states which increased their speed limits saw fatalities fall by an average of 3.4 to 5.1 percent. The study author, economist Charles Lave of the University of California at Irvine, said part of the drop appeared to be from drivers switching away from back roads to safer freeways now that they could drive faster on them. Also highway patrols shifted resources away from pulling over safe but speeding drivers and towards catching unsafe drivers.

Lave also speculated that reducing "speed variance" might have made the highways safer. Speed variance means vehicles passing each other - the most likely time for a crash to occur on an interstate highway. By eliminating an artificially low speed limit and allowing drivers to drive closer to what feels natural, raising speed limits can reduce variance, thereby reducing passing and crashes and deaths.

Indeed, an earlier AAA report looking at a number of different studies confirmed "accident rates increase with increasing speed variance for all classes of roads." This is why it wasn’t smart for the Senate bill to maintain the national speed limit for commercial trucks and buses, effectively ensuring they will go slower than cars. What’s worst about the national speed limit’s approach to saving lives is that it uses a shotgun approach, instead of dealing with specific problems.

For example, drivers under the age of 20, for example, are involved in more than twice as many fatal accidents as those over 20. Such a disparity results in part from a system that makes getting a driver’s license far easier than passing a high school final exam. Make driving a privilege instead of a right and watch traffic deaths plummet.

Finally, even were it conclusively proven that the national speed limits saves lives, it would not be the end of the matter. Why not just lower speed limits all the way down to 20? For that matter, why not mandate that we all drive armored cars?

Because all safety regulations involve tradeoffs. A speed limit is a tradeoff between allowing people and goods to get to their destinations quickly and the possibility of more accidents. Contrast this with seat-belt laws, which impose a real but tiny inconvenience and reap a tremendous award.

In any case, why congressmen from tiny Rhode Island are better able to make the speed-versus-time decision for huge states like Texas is beyond comprehension. Let’s let the states set the speed limits where they think they belong and then focus on more useful laws the states can implement that will reduce the deaths on our nation’s roads.