Car's 'black box' and what it tells

The modern EDR grew out of research begun in the 1970s, as carmakers tinkered with sensors that could reliably trigger air bags. The big carmakers, technical editor Warren Webb explained in Electronics Design, Strategy, News, knew customers wouldn't pay extra for a safety item if they didn't believe it actually made them safer. As air-bag controls grew more sophisticated, so did the ability to gather data, Webb wrote.

One early court test involved the reliability of the black box in the Corvette of Eagles star Jerome Brown, who died in a one-car crash in Florida in 1992. In 1999, Brown's survivors sued GM for $30 million, claiming the air bag in his car deployed when he hit a pothole, causing him to smash into a tree. However, black-box data showed the air bag went off, properly, on impact, and the family lost the case.

EDRs have evolved enormously since then - and will continue to do so, said George Hoffer, a Virginia Commonwealth University professor who studies the auto industry.

"It's the ultimate Big Brother," he said. "Where does it stop?"

Hard to say.

But McCartt, of the Insurance Institute, hopes privacy concerns can be assuaged, as the black box is too valuable to limit its use.

"EDR data just have really enormous, almost unlimited, potential to help us understand information about crashes," she said.

So, does her car have one?

She paused. "I don't know."