Federal Study Finds Lighter Vehicles Cause More Deaths

Published November 21, 2003

Reducing the weight of cars and sport utility vehicles (SUVs) results in significantly higher death rates among American motorists, concluded an October 14 study by the National Highway Transportation Safety Administration (NHTSA).

The study is expected to have important implications for the NHTSA’s ongoing examination of new fuel economy mandates that would inevitably downsize the nation’s cars and light trucks.

Hundreds More Will Die

The new study found that weight reductions in the most popular SUVs—those weighing less than 5,000 pounds—would make travel significantly less safe for vehicles’ occupants. Most SUVs are used by families to transport their children.

For the popular light and midsized SUVs, such as the Ford Explorer, a 100-pound reduction in weight would result in 234 additional traffic fatalities every year.

The study also determined that the most fuel-efficient cars have a fatality rate twice that of even the smaller SUVs, and four times the fatality rate of minivans. A 100-pound reduction in the weight of small passenger cars, such as the Toyota Corolla, would result in 597 additional deaths every year.

“The study confirms what we’ve known for a long time, that the downweighting of vehicles has an adverse impact on safety,” said Eron Shosteck, spokesperson for the Alliance of Automobile Manufacturers.

Questioning CAFE

The timing of the study is significant, as the NHTSA is currently considering proposals to force vehicles sold in the U.S. to become more fuel-efficient. Prior restrictions on fuel economy have required automakers to lightweight their vehicles.

“We’re probably not too far away from releasing a notice on our thoughts on post-2007 fuel economy,” said NHTSA spokesperson Rae Tyson on October 14. “I would say weeks rather than months.”

Although the study adds to the weight of evidence that fuel economy standards sacrifice human life for energy conservation, the NHTSA did not explicitly reach that conclusion in its report.

“The NHTSA press release accompanying the study makes no mention of its implications for CAFE,” according to a statement issued by the Competitive Enterprise Institute.

Nevertheless, asserted CEI, the study “indicates that its fuel economy program (CAFE) is even deadlier than previously estimated.

“In 2001, a National Academy of Sciences panel concluded that CAFE contributes to between 1,300 and 2,600 traffic deaths per year, by restricting the production of large cars. NHTSA’s newest study, however, finds that the effect of this downsizing on safety is ‘substantially larger’ than previously thought.”


James M. Taylor is managing editor of Environment & Climate News. His email address is [email protected].


For more information …

The full 334-page text of the NHTSA’s October 2003 report, Vehicle Weight, Fatality Risk, and Crash Compatibility of Model Year 1991-99, is available through PolicyBot. Point your Web browser to http://www.heartland.org, click on the PolicyBot icon, and search for document #13559. A 23-page summary is available as document #13560.