THE SHAPE OF SUVS

America’s favorite vehicle could become an endangered species. The so-called sport utility vehicle, or SUV, has been an object of controversy and the butt of talk-show jokes. Now the nation’s chief auto safety regulator has it in his sights. Jeffrey W. Runge, administrator of the National Highway Traffic Safety Administration, has made that clear in interviews and speeches.

Speaking of pickups and SUVs, he told The New York Times: “The theory that I’m going to protect myself and my family even if it costs other people’s lives has been the operative incentive for the design of these vehicles, and that’s just wrong. Not to sound like a politician, but that’s not compassionate conservatism.” He told The Wall Street Journal that consumers should think twice before buying them.

Dr. Runge, who was an emergency room physician in Charlotte, N.C., accepted the Washington job partly because of an accident victim who never made it to the hospital. He recalls with horror the death of 17-year-old Sarah Longstreet on her way to high school. She was killed when a 1991 Ford Explorer collided with her Mazda sedan.

Drivers like SUVs because of their reputation for safety, because they are big and powerful, and sometimes because they are threatening and intimidating to other motorists. Critics object that they are deadly in collisions with smaller cars, get poor gasoline mileage and often have such large profiles that they block visibility at intersections and in parking lots.

The safety argument comes partly from the size and strength of SUV frames and bodies, but also because of their height off the ground. In a collision with a smaller car, bumpers and frame rails can override a smaller car’s bumper or doorsill. Dr. Runge says that when a light truck hits a car in the side, the car’s occupants are 26 times as likely to die as the truck’s occupants. But the safety notion can be illusory. SUVs roll over three times as often as cars. And SUV rollovers more often end with fatalities.

Safety-minded motorists who check with the five-star rollover crash ratings on the safety administration’s Web site often insist on at least four stars. Only two SUVs made four stars in the 2002 ratings, the Pontiac Aztek 4-dr and the Acura MDX. The rest were mainly two-star and three-stars.

Dr. Runge has teams preparing recommendations on what to do about rollover and compatibility – how different vehicles match up in a collision. He can set safety standards for vehicle manufacturers, but the Bureau of the Budget, which rejected a tire-safety proposal last year, must review them.

Enthusiasts for the SUVs can hope that manufacturers will make them safer, by lowering their frames and improving air bags. Critics can hope for the same thing.