WASHINGTON - One was a lumber salesman who crippled a 78-year-old woman. Another was driving a toy company’s van when he killed a college sophomore. When a cable company driver rammed a stopped car at 71 miles per hour, a woman and her mother died. A driver in a company car didn’t react when traffic slowed, hitting a Honda and killing a 32-year-old woman.

All four drivers were using their cellphones. At a time when the National Safety Council estimates that about one-quarter of all crashes involve cellphones or texting - about 1.2 million accidents a year - these four crashes had something else in common.