A seat belt would have made the difference for Natalie Thompson. Instead of spending this week preparing for Christmas, the family of the 17-year-old girl will prepare for her funeral.

The Salt Lake teenager was killed last weekend. She was a back-seat passenger in a car that went through an intersection and was hit broadside by another vehicle.None of the six other occupants in the vehicle was wearing a seat belt either, said Salt Lake police Sgt. Scott Folsom. Two occupants were seriously injured; the others were treated and released from area hospitals.

"What killed this girl, and this is still under investigation, was she wasn't wearing a seat belt and she was partially ejected," Folsom said of the early Saturday accident at 27th South and Ninth East.

"Had they all been wearing their seat belts, the likelihood was no one would have been seriously injured," said Folsom, who is the investigating sergeant in the department's traffic division.

Consumer safety groups have howled for years to get harness-type restraint devices for the back seats of vehicles. The federal government now requires all vehicles made after 1990 to have the shoulder-harness seat belt for the back seats.

But an estimated 150 million cars on U.S. roads have the old-style belts.

The Institute for Injury Reduction, a group of trial lawyers involved in automobile accident litigation, has criticized lap-only safety belts and suggested the devices may in some accidents actually cause serious injury.

Despite the arguments that a small percentage of people may be injured in an accident while wearing the lap belts, health and law enforcement professionals contend passengers are better off wearing the devices.

"They're not ejected. We have a lot of our patients who come that are sleeping in the back seat and there are too many of them in the car and they're ejected. And they're either not living or not surviving in a normal state," said Charlene Barrett, nursing supervisor University Health Sciences Center.

Whether the accident victim was wearing seat belt is "the first question we ask," Barrett said.

Rear seat belts "save more people than they hurt," said Folsom, who has seen thousands of accidents in Salt Lake City.