Study Weighs Costs of Cell Phone Use

Harvard research finds no net cost to banning cell phones in cars

Banning cell phone use on the road would save lives and the benefits to society would cancel out the costs of such a ban, according to a study released today by the Harvard Center for Risk Analysis.

The results contradict those from a similar study the center conducted in 2000, which found that a cell phone ban would be “premature” given limited data at the time. That study had been commissioned by AT&T Wireless, but the latest study was independently funded by the center.

The different funding sources did not affect the studies’ conclusions, and the turnaround resulted from information that had not been available when the 2000 report was compiled, according to the latest study’s author.

“The major factor in the change was new federal information on how much people use cell phones,” said Joshua T. Cohen ’86, a senior research scientist at the center. “The new estimate was four times higher.”

The study measured the benefits of a ban by considering medical costs, property damage and estimates of what people would be willing to pay to avoid pain, suffering and death.


That evaluation found that a ban would be worth about $43 billion a year, although the estimate is imprecise and researchers place the range of possible values anywhere from $9 to $193 billion. Those savings would be roughly offset by the economic impact of unmade calls, also estimated to be around $43 billion annually and to range from $17 to $151 billion.

The estimates could prove useful despite the significant uncertainty, according to Cohen. Overall, the ranges suggest that a cell phone ban would be “a wash” in its economic costs and benefits.

He said the risk people face when drivers use cellular phones is fairly small.

A cell phone driver has a 13 in 1,000,000 chance of dying per year, but for pedestrians and other drivers the chance of getting killed because of someone else using a cell phone on the road is just 4 in 1,000,000, according to Cohen.

That finding suggests other measures, such as reducing the speed limit, could be more effective in reducing motor vehicle fatalities and more cost effective.

But even these small risks can add up. The center’s study estimated that the use of cell phones by drivers results in about 2,600 deaths and more than 500,000 injuries each year in the United States.

Researchers acknowledged these figures remain imprecise. The number of fatalities could range from 800 to 8,000 and the estimate of injuries is between 100,000 and 1 million.

“While the risk to any individual driver or passenger or pedestrian is very low, because so many people use cell phones now, the overall risk to society raises an important issue for policy makers,” Cohen said.

The idea of banning cell phones while driving remains a controversial political issue, and several students who hold opposite opinions on the subject said the study would only reinforce their view.

“Given that the economics are the same, and there are innocent lives being lost on one side and not on the other, I don’t think there is a question of where we should go,” said Andrew Chi ’05, a regular cell phone user.

But Qian Zhang ’04, another cell user, said a ban would be more trouble than it is worth.

“Since the study took into account how much people value their own lives, and the economic consequences are equal, I think we should just keep things the way they are to save time,” he said.