Here's a surprising result: Looking purely at the frequency of crashes before and after enactment, new laws that restrict the use of handheld cellphone use (calling and/or texting) while driving produce no recognizable reduction in crashes.
So find researchers from the Highway Loss Data Institute, an organization that is funded by the insurance industry. They looked at the rates of monthly collision claims per 100 insured vehicle years—one car insured for one year—for vehicles up to three years old in the months right before and after hand-held bans went into effect in New York (November 2001), D.C. (July 2004), Connecticut (October 2005), and California (July 2008). This data set was then compared with nearby areas without a ban—for instance, D.C. was compared both with statewide trends in Virginia and Maryland, and with the city of Baltimore.
The methodology effectively corrected for economic swings, seasonal changes in driving changes, and other variables, the researchers say.
The HLDI observed drivers in the affected areas and found that handheld use was down significantly after the ban—but that somehow didn't lead to a lower accident rate.
"The laws aren't reducing crashes, even though we know that such laws have reduced hand-held phone use, and several studies have established that phoning while driving increases crash risk," summed Adrian Lund, the president of the Insurance Institute for Highway Safety (IIHS) and the HLDI, in a release.
A large-scale Virginia Tech Transportation Institute study released last summer, with data gathered via cameras, of real-world drivers, found that drivers using handsets were at several times the risk of a crash or near-crash when dialing and up to 23.2 times the risk when texting (for truck drivers). U.S. Transportation Secretary Ray LaHood is taking these results, along with others suggesting various levels of distraction, very seriously and earlier this week announced a nationwide texting ban for commercial truck drivers.
The results of the HLDI research are to be presented to the SAE Government/Industry Meeting in Washington, D.C. today.
One possibility is that hands-free phones might be placing users at virtually the same overall risk as hand-held devices, despite recent results linking higher rates of distraction with the physical act of pushing buttons and holding the phone. Another possibility yet is that with a migration to "safer" hands-free options, people are communicating more while driving—or that for some drivers, having their hands free frees them up for other types of distractions, like eating or drinking.
"So the new findings don't match what we already know about the risk of phoning and texting while driving," Lund points out. "If crash risk increases with phone use and fewer drivers use phones where it's illegal to do so, we would expect to see a decrease in crashes. But we aren't seeing it."
There's surely more to this story, and the HLDI is now gathering data to try to understand the other factors involved and why the perceived lowering of risk didn't result in a reduced crash rate. Stay tuned.
Currently just seven states—California, Oregon, Washington, New York, New Jersey, and Connecticut—have full hand-held bans in effect for all drivers; four others—Texas, Louisiana, Arkansas, and Illinois—have partial bans. Hand-held cellphone bans affecting only young drivers are now enforced in 21 states plus the District of Columbia.