July 11, 2011
Do Increased Fuel Mileage Standards Make It More Dangerous to Drive?

So a post from one of my followers, who works for the Richmond Times-Dispatch, got me thinking. While I can’t find the original post, I have linked to the followup post he made in which he explored the question of whether making cars more fuel efficient would necessarily lead to more deaths on the highways. You can read Barticles’ post here.

Barticles, who blogs from an interesting, right-libertarian perspective, concluded that increased fuel economy standards will inevitably lead to more road deaths in America—ceteris paribus (everything else being equal). Several reasons pop to mind why this might be true: cars that are more fuel efficient also tend to be smaller, and smaller vehicles might provide less protection from accidents than bigger ones—especially in wrecks between large and small vehicles. Greater fuel efficiency might also make driving cheaper, thus encouraging more miles be driven, and thereby increasing the opportunity we all have to run into one another—literally. Logically, then, increasing requirements for miles per gallon might well increase American highway fatalities—an example of the law of unintended consequences.

As it happens, car manufacturers have spent 40 years screaming that more fuel efficient cars will be small and dangerous and that Americans will die in huge numbers if manufacturers are forced to sell fuel efficient death traps to the general public. (That it is much easier to make money on a big, luxurious vehicle than it is on a cheap econobox plays no part in their calculation, I am sure.) Indeed, as a long time subscriber (in print no less!) to a range of car magazines, and as someone who believes that the boys with car toys BBC show Top Gear is the funniest, best produced show on TV (but not the American version, which is abysmal), I have seen screed after screed that all comes to the same conclusion: increased fuel efficiency standards will cause deaths because Americans will drive their now-unsafe cars more.

Notably, there are some logical gaps in Barticles’ argument: for example, if the roads in a high mileage American future are so dangerous we all start killing each other in car wrecks, my guess is we’ll drive less, and so the death rate would go down. But the real problem with the argument is that in the real world, nothing is ceteris paribus. Nothing is ever held equal. And in the real world, the evidence is entirely against him.

Three easily available pieces of evidence demonstrate the utter falsehood of the claim that fuel efficient cars lead to more highway deaths.

In the late 1970s, passenger cars in the US barely averaged 17 mpg. Today they average over 27. (My European readers will scoff at such tiny numbers, but there you are.) In 1971, Americans collectively drove a little less than 1.2 trillion miles. Today, they drive nearly 3 trillion miles per year. In 1971, there were 52,542 highway deaths in the US. In 2009, there were 30,797 deaths.

Put simply, Americans have spent 40 years driving cars that have gotten more fuel efficient over time. They have been driving them more miles per year. And yet fewer Americans die on the road than died 40 years ago.

There are many reasons for why we don’t die in car wrecks as much as we used to despite driving more miles in more fuel efficient cars, of course. Cars today have anti-lock brakes and airbags. Most states have mandatory seat belt laws; seat belts weren’t even standard equipment in cars until 1973 or so. (Notably, manufacturers screamed that the cost of installing seat belts would make their cars uncompetitive in the marketplace… just as they did with airbags and anti-lock brakes.) We have drunk driving laws and designated drivers. We’ve rebuilt highways to make access easier and more predictable.

But the fact is that cars are more fuel efficient today than they were 40 years ago. They are driven more miles per year than they used to be. And fewer Americans die on the highways than used to.

Making cars more fuel efficient does not necessarily lead to more highway deaths. This isn’t a matter of abstract logic. It’s a matter of evidence.