Contradicting claims equating drunk driving with cellphone use behind the wheel, a University of Colorado Boulder study has found no evidence of decreased accident rates following California’s usage ban.
The potential dangers of distracted driving have been well established, however the latest research, published in the journal Transportation Research Part A: Policy and Practice, suggests the real-world implications may not be as substantial as safety advocates have claimed.
“If it’s really that dangerous, and if even just a fraction of people stop using their phones, we would expect to find some decrease in accidents,” said co-author Daniel Kaffine, associate professor of economics at CU-Boulder. “We didn’t find any statistical evidence of a reduction.”
The study compared accident data from California before and after the state enacted its 2008 ban on handheld cellphone use by drivers. The researchers attempted to correct the data for bad weather, gas prices and other variables that are known to influence accident rates.
Kaffine proposes several theoretical explanations for the findings, including the possibility that hands-free devices are just as distracting. The type of driver who would be most distracted by handheld cellphone use may also be prone to distraction from a long list of other things in a car, such as a radio or navigation system.
The researchers considered the possibility that few people were complying with the law, however separate studies are said to have found that cellphone usage rates typically drop when restrictive laws are put in place.
Perhaps more importantly, the professor suggests previous laboratory studies — performed in simulators — may have misinterpreted how people actually use cellphones in vehicles. Cellphones have been directly linked to many fatal accidents, however most drivers may be more careful in their usage habits.
“Disentangling these effects will be useful for policymakers in other states who are considering policies to address distracted driving,” Kaffine said. “However, our results suggest that simply banning hand-held cellphone use may not produce the desired increase in traffic safety.”