There’s an argument against higher fuel economy that’s often dismissed by environmentalists, but resonates with a lot of people. The line of reasoning goes like this: small cars may be more fuel-efficient, but big cars are safer. If you took this to its logical conclusion, of course, we’d all be doing our car buying at Ed’s Used Monster Truck and Big Rig Emporium. But is this really a choice we have to make?

There is evidence to support the bigger-is-safer theory. When the National Research Council assessed the impact of federal fuel economy rules in 2002, they concluded that one of the downsides was auto safety. In the 1970s and 1980s, manufacturers had made cars smaller and lighter to improve mileage, and the research council concluded that led to an additional 1,300 to 2,600 traffic fatalities in 1993. Just to put those numbers in perspective, nearly 34,000 people died in traffic accidents in 2009.

The government has taken that research seriously. When both the Bush and Obama administrations decided to raise fuel-economy standards, they tried to do it without forcing manufacturers into making smaller cars. Instead of across-the-board rules, the latest standards factor size into the equation. Instead of requiring specific car models to meet specific numbers, manufacturers have overall goals they have to meet: smaller cars are expected to have higher mileage, while bigger vehicles have lower targets.

Yet, auto safety is actually a complicated phenomenon, and if you examine the trends, the most striking thing is how much safer the roadways are than they used to be. If you look at it by traffic deaths per miles traveled, we’ve cut the death rate by more than half over the past 35 years (there were 3.2 fatalities for every 100 million vehicle miles traveled in 1975; by 2009, that was down to 1.13). That’s even more impressive when you consider that the U.S. population has increased by more than 80 million people over that time, and we’re driving more than twice as many miles per year.

Those who make the connection between size and safety point out that after slimming down in the 1980s, the average American light-duty vehicle has bulked up over the past two decades. Today’s average weight of about 4,000 pounds, however, has only brought American vehicles back to the size they were in 1975. But the auto death rate then was more than double what it is now.
The average American car started big, got smaller, then bulked up again, but the traffic death rate has consistently gone down. (NHTSA graph)

There are a lot of things going on here. The National Highway Traffic Safety Administration says traffic deaths drop during recessions, because people (and particularly teenagers who don’t have a lot of money) cut back on their travel, so that has affected the recent numbers. It’s also true that some notable safety advances have come into play: improved air bags, antilock brakes, and daytime running lights, for a start.

There have also been many social changes as well. All 50 states now have mandatory seat-belt and child-restraint laws. Attitudes about drunk driving have changed dramatically – and so have the penalties. In the TV series Mad Men, set in the 1960s, there are scenes of parents letting their children crawl around inside a moving car, of people swigging while they drive, and even shouting pointers to a drunk trying to start his car (“Your lights, Roger! Don’t forget your lights!”). There’s more truth in that picture of a cavalier attitude about driving than your parents or grandparents might care to admit.

Federal officials have even higher hopes for new technology entering the market, like electronic stability control, which allows for computer-controlled braking of individual wheels. That alone could save 5,300 to 9,600 lives.

What’s more, it’s worth remembering that the biggest factor in traffic accidents isn’t the car at all, but how the human beings driving the car choose to drive. The National Highway Traffic Safety Administration says that the major contributors to traffic deaths are alcohol (32 percent of all cases), and not wearing a seat belt (a whopping 54 percent).

Energy choices are full of tradeoffs – that’s inevitable. And it’s our failure, as a nation, to make tradeoffs that are keeping us from solving our energy and climate problems. But maybe one tradeoff we don’t have to make is between “big” and “dead” when it comes to driving.


  1. Walt
    October 21, 2011, 3:56 pm

    Anytime someone claims that SUVs are safer, I respond, “Maybe for you, but tell that to the poor chap you kill”.

    One of my favorite quotes about safety is by Joe Simpson, in Touching the Void:
    “These safety measures introduced to make motoring survivable have made people drive faster and more dangerously. I’ve always agree that the most effective safety device would be a viciously sharp spike protruding from the center of the steering wheel to a point some ten inches from the driver’s chest. No seat belts allowed.”

  2. Phil Cooper
    San Jose, California
    October 12, 2011, 6:38 pm

    Daytime running lights as a safety feature? Whoever thought of this lame idea apparently never heard of Project Yehudi, a British scheme in World War II to make aircraft disappear against the sky background by mounting sealed beam lights on them.

    One version of the story is that American auto manufacturers copied daytime running lights from the Europeans. When the source was traced to Volvo, they explained that they had copied it from Greyhound Bus Lines in the U.S., who gave orders to their drivers to run with headlights on in the daytime after too many motorists claimed they had run into their buses because “they didn’t see them”.

  3. Noah
    October 12, 2011, 10:15 am

    Whether you drive a small car or a big truck, you can never tell if its safe or not. I would use both fuel efficient small cars and those big time SUV’s just to indulge my love to cars. And you are right, people are the one to blame why accidents happen.

    Health and Wellness