Q&A: Cellphones, texting and driving

March 2013

1 How many people use cellphones to talk or text?

Cellphone use in the United States has grown quickly during the past decade. There were about 322 million wireless cellphone subscribers as of June 2012. CTIA – The Wireless Association. 2012. CTIA's semi-annual wireless industry survey results, June 1985-June 2012. Washington, DC. Available: http://files.ctia.org/pdf/CTIA_Survey_MY_2012_Graphics-_final.pdf. Accessed: March 21, 2013.  That's up 32 percent since June 2007 and 2.4 times the number of subscribers in June 2002. Since June 2007, minutes of use have increased 18 percent to 2.3 trillion. Texting has grown even more rapidly. Text messages soared to about 2.3 trillion in the year ending June 2012 — more than 9 times the number in June 2007.  

2 Do drivers frequently talk on the phone or text behind the wheel?

Yes, though it's hard to accurately determine just how often. Federal observational data indicate that 5 percent of drivers in 2010 were talking on hand-held phones at any moment during the day. This means about 660,000 passenger vehicles on the road at any moment during the day were driven by people talking on hand-held
phones. National Highway Traffic Safety Administration. 2011. Driver electronic device use in 2010. Report no. DOT HS-811-3517. Washington, DC: U.S. Department of Transportation. Combining this observational data with self-reported data on hand-held and hands-free phone use, the government estimates that the number of drivers having phone conversations nearly tripled during 2000-08, from 4 percent to 11 percent, and then declined to 9 percent in 2009-10. The percentage of drivers who were observed texting or otherwise manipulating hand-held devices increased 50 percent from 0.6 percent in 2009 to 0.9 percent in 2010.

A 2009 Institute telephone survey of 1,219 drivers 18 and older indicates phone use may be somewhat lower than government estimates. Farmer, C.M.; Braitman, K.A.; and Lund, A.K. 2010. Cellphone use while driving and attributable crash risk. Traffic Injury Prevention 11(5):466-70.  Drivers on average reported spending about an hour in the car each day, with about four minutes of that time on the phone. This translates into roughly 7 percent of time behind the wheel on the phone.  The Institute’s estimate is consistent with an analysis of cellphone use among a small sample of volunteer drivers who were continuously videotaped while participating in a field operational test of crash avoidance technologies in 2009-10. During the first week, before the crash avoidance technologies were activated, drivers engaged in hands-free or hand-held cellphone conversations about 7 percent of the time. Funkhouser, D. and Sayer, J. 2012. A naturalistic cell phone use census (Paper No. 12-4104). In Transportation Research Board 91st Annual Meeting Compendium of Papers. Washington, DC: Transportation Research Board.

In the Institute’s 2009 survey, 13 percent of drivers of all ages reported texting while driving. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8. In a survey conducted by the U.S. government in 2011, 18 percent of drivers older than 18 said they had sent a text message or e-mail while driving. Tison, J.; Chaudhary, N.; and Cosgrove, L. 2011. National phone survey on distracted driving attitudes and behaviors. Report no. DOT HS 811-555. Washington, DC: U.S. Department of Transportation.

3 Who is most likely to use a cellphone while driving?

Young drivers are more likely than other drivers to talk on hand-held cellphones, according to national daytime observational surveys the federal government conducted in 2010. Seven percent of drivers ages 16-24 were observed talking on hand-held phones, compared with 5 percent of those ages 25-69 and 1 percent of drivers 70 and older. National Highway Traffic Safety Administration. 2011. Driver electronic device use in 2010. Report no. DOT HS-811-3517. Washington, DC: U.S. Department of Transportation. In the Institute's 2009 survey of drivers' self-reported phone use, people younger than 30 spent 16 percent of driving time on the phone, compared with 7 percent for drivers 30-59 years old and just 2 percent for drivers 60 and older. Farmer, C.M.; Braitman, K.A.; and Lund, A.K. 2010. Cellphone use while driving and attributable crash risk. Traffic Injury Prevention 11(5):466-70.  In an online survey of 872 licensed drivers conducted in 2012, 74% of drivers 18-29 years-old said they talked on hand-held cellphones while driving compared with 57% of all drivers surveyed. State Farm. 2012. Distracted Driving. Available: http://www.multivu.com/assets/56793/documents/56793-Distracted-Driving-Consumer-Survey-2012-original.pdf. Accessed: March 21, 2013.

Young drivers also are more likely to report texting while driving compared with older drivers. In the 2009 Institute survey, 43 percent of 18-24-year-old drivers reported texting while driving compared with 13 percent of drivers of all ages. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8. A 2011 survey conducted by the federal government found that 44 percent of drivers 18-20 years old and 49 percent of drivers 21-24 years old reported having sent a text message or e-mail while driving. Tison, J.; Chaudhary, N.; and Cosgrove, L. 2011. National phone survey on distracted driving attitudes and behaviors. Report no. DOT HS 811-555. Washington, DC: U.S. Department of Transportation. Only 18 percent of all drivers included in this study reported the same. In the 2012 online survey twice as many 18-29 year-old drivers said they texted while driving compared with all drivers surveyed.

People who are riskier drivers also may use cellphones more frequently while driving than other drivers.  A recent study compared self-reported frequency of cellphone use while driving with driving performance monitored on actual roads. Drivers who reported using cellhpones frequently drove faster, changed lanes more often and made more hard braking maneuvers than drivers who said they rarely used cellphones while driving. Zhao, N.; Reimer, B.; Mehler, B.; D’Ambrosio, L. A.; and Coughlin, J. A. 2013. Self-reported and observed risky driving behaviors among frequent and infrequent cell phone users. Accident Analysis and Prevention  In press.

4 How does using a cellphone or texting while driving affect crash risk?

Two controlled studies link talking on a cellphone directly to increased crash risk. A 2005 Institute study of drivers in Western Australia found cellphone users 4 times as likely to get into crashes serious enough to injure themselves. McEvoy, S.P.; Stevenson, M.R.; McCartt, A.T.; Woodward, M.; Haworth, C.; Palamara, P.; and Cercarelli, R. 2005. Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study. British Medical Journal 331(7514):428.  The study used cellphone billing records to verify phone use of crash-involved drivers. Increased risk was similar for males and females, drivers younger than 30 and those 30 and older and hands-free and hand-held phones. The findings were consistent with 1997 research that showed phone use among Canadian drivers was associated with a fourfold increase in the risk of a property damage crash. Redelmeier, D.A. and Tibshirani, R.J. 1997. Association between cellular-telephone calls and motor vehicle collisions. The New England Journal of Medicine 336:453-58.  The Canadian study also used cellphone billing records to verify phone use by drivers. A recent study independently determined driver culpability in a set of police-reported crashes in British Columbia and found that drivers using cellphones at the time of the crash were 70 percent more likely to be responsible for the crash than drivers not using cellphones. However, cellphone use can't be reliably documented in police crash reports so this estimate is likely imprecise. Asbridge, M.; Brubacher, J. R.; and Chan, H. 2012. Cell phone use and traffic crash risk: a culpability analysis. International Journal of Epidemiology 2012:1-9.

Research linking texting to crash risk is sparse. In a study of large trucks instrumented with video cameras and other monitoring technology, the odds of a traffic conflict, lane drift, near-crash or crash were 23 times higher when a truck driver was texting. Olson, R.L.; Hanowski, R.J.; Hickman, J.S.; and Bocanegra, J. 2009. Driver distraction in commercial vehicle operations. Report No. FMCSA-RRR-09-242. Washington, DC: Federal Motor Carrier Safety Administration.  A limitation of the study is that less than 1 percent of the incidents were crashes; most were lane drifts or other driver errors. It’s not known how such incidents relate to actual crashes, and it's also unclear whether the results generalize to passenger vehicle drivers. 

5 How many crashes have been caused by drivers using cellphones?

Based on analysis of police-reported data from the U.S. Department of Transportation’s Fatality Analysis Reporting System, 3,331 people were killed in motor vehicle crashes that involved distracted driving in 2011. Insurance Institute for Highway Safety. 2013. [Unpublished analysis of data from the U.S. Department of Transportation's Fatality Analysis Reporting System and the NASS General Estimates System]. Arlington, VA.  Cellphone use was indicated as a contributing factor in 12 percent of these crashes. According to data from a nationally representative sample of police-reported crashes of all severities, 393,355 people were injured in crashes that were reported by police to have involved distracted driving. Five percent of these injuries involved talking, listening, dialing or other cellphone use.  However, these estimates are imprecise and likely underestimate distraction's role in crashes, as many police reports don't have information on distracting events. Police crash reports aren't a reliable way to count cellphone-related collisions because drivers often don't volunteer that they were on the phone.

Estimates of the crash risk of cellphone use have been used to project the expected number of crashes linked to cellphone use while driving. An Institute analysis suggests this practice could account for 22 percent of all crashes, or about 1.3 million in 2008, based on how frequently motorists admitted using cellphones while driving and an estimated four-fold increase in the risk of crashes while on the phone. Farmer, C.M.; Braitman, K.A.; and Lund, A.K. 2010. Cellphone use while driving and attributable crash risk. Traffic Injury Prevention 11(5):466-70. However, there is a disconnect between estimated crashes due to cellphone use and real-world crash trends, which indicate that crashes have been declining in recent years, even as driver phone use has increased. About 5.3 million police-reported crashes occurred during 2011, the latest year for which federal data are available. This count is less than the estimated 6-6.8 million crashes recorded annually during the early to mid 1990s, when cellphones started becoming popular, and it is lower than the 6.4 million crashes in 2000, when federal researchers began documenting the increase in phone use while driving.

An increase in crashes isn't showing up in insurance claims either. An analysis by the Highway Loss Data Institute (HLDI) indicates that the frequency of insurance claims for crash damage filed under collision coverage during 1998-2011 has declined. Highway Loss Data Institute. 2013. [Unpublished analysis of collision claim frequencies].  Arlington, VA.

6 How do cellphone use and texting affect drivers and driving performance?

The effect of cellphone use on driving performance has been extensively researched. An Institute review of cellphone and driving research found that out of 54 experimental studies using driving simulators or vehicles instrumented with video cameras, sensors and other equipment, nearly all reported that some measures of driver performance were affected by the cognitive distractions associated with cellphone tasks. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106. Phone conversation tasks typically increased reaction times, reduced speeds and increased lane deviations and steering wheel movements. Statistical analyses that aggregated the results of 33 studies in one analysis and 23 in another reported similar findings. Caird, J.K.; Willness, C.R.; Steel, P.; and Scialfa, C. 2008. A meta-analysis of the effects of cell phones on driver performance. Accident Analysis and Prevention 40(4):1282-93. Horrey, W.J. and Wickens, C.D. 2006. Examining the impact of cell phone conversations on driving using meta-analytic techniques. Human Factors 48(1):196-205. The Institute review also found that in the few studies that explicitly examined it, dialing on a cellphone affects driver performance. Like phone conversations, dialing leads to longer reaction times and greater variability in steering. Unlike conversation, however, drivers generally take their eyes off the road when dialing or manipulating a hand-held phone and may take longer glances away from the roadway than when tuning the radio or performing similar tasks. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106.

One reason cellphone conversations degrade driving performance is that listening and processing information from a phone conversation draws mental resources away from driving. Using functional magnetic resonance imaging, researchers at Carnegie Mellon University found a 37 percent reduction in brain activity associated with driving when research subjects listened via a headset to spoken sentences that they judged as true or false while steering in a driving simulator. Just, M.A.; Keller, T.A.; and Cynkar, J. 2008. A decrease in brain activation with driving when listening to someone speak. Brain Research 1205(2008):70-80. Other studies measuring activity in the brain have found similar suppression of signals in brain areas associated with visual processing and attention during distracted driving. Bowyer, S.M.; Hsieh L.; Moran, J.E.; Young, R.A.; Manoharan, A.; Liao, C.J.; Yu, Y.; Chiang, Y.; and Tepley, N. 2009. Conversation effects on neural mechanisms underlying reaction time to visual vents while viewing a driving scene using MEG. Brain Research 1251(28):151-61. Strayer, D.L.; Martinez, M.; Cooper, J.M.; and Drews, F.A. 2006. Brain waves suppressed by cell phone conversations (pp. 2364-2367). Proceedings of the human Factors and Ergonomics Society 50th Annual Meeting. The diversion of mental resources from driving to cellphone conversation can result in a phenomenon known as “inattention blindness” where drivers fail to “see” or process information from objects in the roadway even when they are looking at them. Strayer, D.L.; Drews, F.A.; and Crouch, D.J. 2003. Fatal distraction? A comparison of the cell-phone driver and the drunk driver,Proceedings of the Second International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design, 25-30. Iowa City, IA: University of Iowa Public Policy Center.  There is some evidence that mind wandering reduces people's ability to process visual information and, if intense enough, may even increase crash risk. Barron, E.; Riby, L. M.; Greer, J.; and Smallwood, J. 2011. Absorbed in thought: the effect of mind wandering on the processing of relevant and irrelevant events. Psychological Science 22(5):596-601. Galera, C.; Orriols, L.; M’Bailara, K.; Laborey, M.; Contrand, B.; Ribereau-Gayon, R.; Masson, F.; Bakiri, S.; Gabaude, C.; Fort, A.; Maury, B.; Lemercier, C.; Cours, M.; Bouvard, M.P.; and Lagarde, E. 2012. Mind wandering and driving: responsibility case-control study. BMJ 2012(345).

Conversations and other cognitive distractions also change the way drivers scan the roadway environment and process information. Drivers engaged in cognitive distractions like cellphone conversations tend to concentrate their gaze toward the center of the roadway Recarte, M.A. and Nunes, L.M. 2000. Effects of verbal and spatial-imagery tasks on eye fixations while driving. J. Exp. Psychol. Appl. 6(1):31-43. Recarte, M.A. and  Nunes, L.M. 2003. Mental workload while driving: effects on visual search, discrimination, and decision making. J. Exp. Psychol. Appl. 9(2):119-37. Reimer, B.; Mehler, B.; Wang, Y.; and Coughlin, J. F. 2012. A field study on the impact of variations in short-term memory demands on drivers’ visual attention and driving performance across three age groups. Human Factors 54(3):454-68.
and look at their mirrors, instrument clusters and other peripheral areas significantly less often. Recarte, M.A. and Nunes, L.M. 2000. Effects of verbal and spatial-imagery tasks on eye fixations while driving. J. Exp. Psychol. Appl. 6(1):31-43. Recarte, M.A. and  Nunes, L.M. 2003. Mental workload while driving: effects on visual search, discrimination, and decision making. J. Exp. Psychol. Appl. 9(2):119-37. Harbluk, J. L.; Noy, Y. I.; Trbovich, P. L.; and Eizenman, M. 2007. An on-road assessment of cognitive distraction: Impacts on drivers’ visual behavior and braking performance. Accident Analysis and Prevention 39(2):372-9.

There hasn't been a lot of research on the safety effects of texting and driving, but three studies of young drivers using driving simulators all found that receiving and especially sending text messages impeded reaction times and lane-keeping ability. Hosking, S.; Young, K.; and Regan, M. 2006. The effects of text messaging on young novice driver performance. Monash University Accident Research Center. Report no. 246. Melbourne, Victoria: Monash University.
Reed, N. and Robbins, R. 2008. The effect of text messaging on driver behavior: a simulator study. Published report PPR 367. Berkshire, United Kingdom: Transport Research Laboratory. Drews, F.A.; Yazdani, H.; Godfrey, C.N.; Cooper, J.M.; and Strayer, D.L. 2009. Text messaging during simulated driving. Human Factors 51(5):762-70.

7 Are hands-free cellphones safer than hand-held cellphones?

No, at least not after the conversation begins. Two studies of crashes using cellphone billing records to verify phone use found about a fourfold increase in crash risk when conversing on either hands-free or hand-held phones. McEvoy, S.P.; Stevenson, M.R.; McCartt, A.T.; Woodward, M.; Haworth, C.; Palamara, P.; and Cercarelli, R. 2005. Role of mobile phones in motor vehicle crashes resulting in hospital attendance: a case-crossover study. British Medical Journal 331(7514):428. Redelmeier, D.A. and Tibshirani, R.J. 1997. Association between cellular-telephone calls and motor vehicle collisions. The New England Journal of Medicine 336:453-58. The studies were unable to estimate crash risk from different types of hands-free devices. They also were unable to determine whether there was any benefit associated with hands-free devices while placing the call. Experimental research using driving simulators indicates that phone conversation tasks, whether using hand-held or hands-free devices, affect some measures of driving performance. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106. Caird, J.K.; Willness, C.R.; Steel, P.; and Scialfa, C. 2008. A meta-analysis of the effects of cell phones on driver performance. Accident Analysis and Prevention 40(4):1282-93. Hands-free phones may eliminate some of the physical and visual distraction of handling phones or dialing, but the cognitive distraction remains.

8 Are cellphone conversations riskier than other distractions or impairments?

Evidence is mixed. Conversations with passengers can be distracting, especially to teenage drivers. An Institute-sponsored review of research studying the effects of passengers on teen drivers indicated that passenger presence increases teen driver crash risk, especially when the passengers are teens. Williams, A. F.; Ferguson, S. A.; and McCartt, A. T. 2007. Passenger effects on teenage driving and opportunities for reducing the risks of such travel. Journal of Safety Research 38(4):381-90. Passenger-related distraction seems to play a large role in crashes involving teenage drivers with teen passengers. Using 2005-07 data documenting the factors that contributed to crashes resulting in injury or property damage, researchers found that in crashes where a teenage driver 16-18 years old was distracted by something inside the vehicle, about 47 percent of females and 71 percent of males were distracted by a peer passenger. Curry, A. E.; Mirman, J. H.; Kallan, M. J.; Winston, F. K.; and Durbin, D. R. 2012. Peer passengers: How do they affect teen crashes. Journal of Adolescent Health 50(6):588-94.

In some cases passengers reduce crash risk. In a study of actual driving where people were videotaped driving for one year, drivers were less likely to be involved in a near-crash or crash when talking to a passenger in an adjacent seat compared with when they were talking on a cellphone. Klauer, S.G.; Dingus, T.A.; Neale, V.L.; Sudweeks, J.D.; and Ramsey, D.J. 2006. The impact of driver inattention on near-crash/crash risk: an analysis using the 100-car naturalistic driving study data. Report no. DOT HS-810-594. Washington, DC: National Highway Traffic Safety Administration. In a different naturalistic study that recorded 16-year-old drivers, there was a 75 percent reduction in the rate of near-crashes and crashes when the teens had an adult passenger compared with when they were driving alone. Simons-Morton, B.G.; Ouimet, M.C.; Zhang, Z.; Klauer, S.E.; Lee, S.E.; Wang, J.; Chen, R.; Albert, P.; and Dingus, T.A. 2011. The effect of passengers and risk-taking friends on risky driving and crashes/near crashes among novice teenagers. Journal of Adolescent Health 49(6):587-93. One possible reason why crash risk might be lower when passengers are present is because passenger conversations can support the driver by pointing out safety risks, helping the driver navigate or modulating the conversation when driving becomes challenging. Driving simulator experiments have shown that conversations with passengers contain more pauses and include more references to the traffic situation or driving environment than cellphone conversations. Charlton, S.G. 2009. Driving while conversing: Cell phones that distract and passengers who react. Accident Analysis and Prevention 41(1):160-73. Drews, F.A.; Pasupathi, M.; and Strayer, D.L. 2008. Passenger and cell phone conversation in simulated driving. Journal of Experimental Psychology: Applied 14(4):392-400.

Naturalistic studies that continuously videotaped people driving found dialing a cellphone increases the risk of crashes, near-crashes and other safety-critical events more than talking on a cellphone. Olson, R.L.; Hanowski, R.J.; Hickman, J.S.; and Bocanegra, J. 2009. Driver distraction in commercial vehicle operations. Report No. FMCSA-RRR-09-242. Washington, DC: Federal Motor Carrier Safety Administration. Klauer, S.G.; Dingus, T.A.; Neale, V.L.; Sudweeks, J.D.; and Ramsey, D.J. 2006. The impact of driver inattention on near-crash/crash risk: an analysis using the 100-car naturalistic driving study data. Report no. DOT HS-810-594. Washington, DC: National Highway Traffic Safety Administration. However, distraction from conversation generally lasts longer than distraction from dialing, resulting in longer exposure to distraction. For instance, in a field operational test of crash avoidance technologies, hand-held and hands-free phone conversations lasted about three minutes on average, but other types of interactions with cellphones only lasted 30 seconds. Funkhouser, D. and Sayer, J. 2012. A naturalistic cell phone use census (Paper No. 12-4104). In Transportation Research Board 91st Annual Meeting Compendium of Papers. Washington, DC: Transportation Research Board. Because of the difference in time spent distracted by a cellphone conversation versus dialing a phone, one study estimated the percentage of crashes and near-crashes attributable to talking on and dialing hand-held phones both at about 4 percent. Klauer, S.G.; Dingus, T.A.; Neale, V.L.; Sudweeks, J.D.; and Ramsey, D.J. 2006. The impact of driver inattention on near-crash/crash risk: an analysis using the 100-car naturalistic driving study data. Report no. DOT HS-810-594. Washington, DC: National Highway Traffic Safety Administration.

Some experimental studies have found that phone conversations are more disruptive than adjusting a radio. McCartt, A.T.; Hellinga, L.A.; and Braitman, K.A. 2006. Cell phones and driving: review of research. Traffic Injury Prevention 7(2):89-106. Two studies reported that talking on a cellphone and having a 0.08 percent blood alcohol concentration (BAC) — the legal threshold for impairment — have comparable effects on some simulated driving tasks. Strayer, D.L.; Drews, F.A.; and Crouch, D.J. 2003. Fatal distraction? A comparison of the cell-phone driver and the drunk driver,Proceedings of the Second International Driving Symposium on Human Factors in Driver Assessment, Training, and Vehicle Design, 25-30. Iowa City, IA: University of Iowa Public Policy Center. Burns, P.C.; Parkes, A.; Burton, S.; and Smith, R.K. 2002. How dangerous is driving with a mobile phone? Benchmarking the impairment to alcohol. TRL Report 547. Berkshire, United Kingdom: Transport Research Laboratory.  However, the risks associated with alcohol impairment accumulate over the entire duration of a trip, whereas the risks of cellphone use generally apply for only a portion of a trip. In addition, crash risk increases substantially at very high BACs.

9 How common are bans on hand-held cellphones and texting?

Bans are widespread in other countries and are becoming more common in the U.S. Ten states (California, Connecticut, Delaware, Maryland, Nevada, New Jersey, New York, Oregon, Washington, and West Virginia) and the District of Columbia have enacted laws that ban drivers of all ages from using hand-held cellphones. School bus drivers in 19 states and the District of Columbia are restricted from using all cellphones while driving a bus.

Hand-held cellphone bans for young drivers are becoming more common. Thirty-six states and the District of Columbia have such restrictions. Distractions of any type are a common factor in crashes of newly licensed 16-year-old drivers. Braitman, K.A.; Kirley, B.B.; McCartt, A.T.; and Chaudhary, N.K. 2008. Crashes of novice teenage drivers: characteristics and contributing factors. Journal of Safety Research 39(1):47-54. Some research also shows teenage drivers tend to use cellphones and other technologies more than adult drivers. Lee, J.D. 2007. Technology and teen drivers. Journal of Safety Research 38(2):203-13.

Text messaging is banned for all drivers in 39 states and the District of Columbia. In addition, novice drivers are banned from texting in Six states (Mississippi, Missouri, New Mexico, Oklahoma, South Dakota, and Texas), and school bus drivers are banned from text messaging in Three states (Mississippi, Oklahoma, and Texas).

Cellphone laws in the U.S.

10 Do drivers comply with bans on hand-held phone use and texting?

Institute research has documented that all-driver bans on hand-held phone use can have large and lasting effects on overall phone use. Based on observations of drivers conducted before bans in New York, the District of Columbia and Connecticut and up to seven years after, driver hand-held cellphone use was an estimated 24-76 percent lower than would be expected without a ban. McCartt, A.T.; Hellinga, L.A.; Strouse, L.M.; and Farmer, C.M. 2009. Long-term effects of hand-held cellphone laws on driver hand-held cellphone use. Traffic Injury Prevention 11(2):133-41.

In the Institute's 2009 telephone survey of cellphone use, 56 percent of drivers in states with bans reported they use phones when driving, compared with 69 percent in states without such laws. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8.  The proportion of drivers who talk on phones and always talk hands-free was 22 percent in states with all-driver bans on hand-held phones and 13 percent in states without all-driver bans.

One Institute study suggested that bans seem to have less effect on younger drivers. Since Dec. 1, 2006, North Carolina has banned the use of any telecommunications device by drivers younger than 18. Observed cellphone use by teenagers leaving high schools in the afternoon five months after the restriction took effect had changed little from the 11 percent observed one to two months before the ban. Foss, R.D.; Goodwin, A.H.; McCartt, A.T.; and Hellinga, L.A. 2009. Short-term effects of a teenager driver cell phone restriction. Accident Analysis and Prevention 41(3):419-24.  Follow-up observations two years later found 10 percent of drivers at the high schools in North Carolina were using phones — again, not significantly different from the pre-ban period.  Teen cellphone use at the comparison sites in South Carolina remained steady at 12-13 percent. Goodwin, A. H.; O’Brien, N.; and Foss, R.D. 2012. Effect of North Carolina’s restriction on teenage driver cell phone use two years after implementation. Accident Analysis and Prevention 48:363-67.

When it comes to texting bans, it appears that drivers, especially young adults, largely shrug them off. An Institute study found that among 18-24 year-olds — the group most likely to text — 45 percent reported texting while driving in states that bar the practice, just shy of the 48 percent of drivers who reported texting in states without bans. Braitman, K.A. and McCartt, A.T. 2010. National reported patterns of driver cellphone use. Traffic Injury Prevention 11(6):543-8. Among drivers 25-29, 40 percent reported texting in states with bans, compared with 55 percent in states without bans.

High-visibility enforcement may be one way to increase compliance of cellphone and texting bans. After programs of publicized, high-intensity enforcement of hand-held cellphone and texting bans were implemented, observed hand-held phone use declined by 57 percent in Hartford, Conn., and 32 percent in Syracuse, N.Y. Observed manipulation of hand-held phones (e.g., dialing, texting) also decreased significantly in both cities following the enforcement initiative. Cosgrove, L.; Chaudhary, N.; and Reagan, I. 2011. Four high-visibility enforcement demonstration waves in Connecticut and New York reduce hand-held phone use. Report No. DOT HS 811-845. Washington, DC: U.S. Department of Transportation.

11 Do bans on hand-held phone use and texting reduce crashes?

Despite any effects on phone use and texting, there is little evidence so far that banning hand-held phone use or texting reduces crashes. A 2009 HLDI analysis found that hand-held bans had no effect on insurance claims. Highway Loss Data Institute. 2009. Hand held cellphone laws and collision claim frequencies. HLDI Bulletin 26(17). Arlington, VA. Researchers compared claims for crash damage in four jurisdictions before and after hand-held phone use bans went into effect and found steady claim rates. A recent study of New York's hand-held cellphone ban found that crash rates in more densely populated areas were lower during the six year period after the ban than they were during a five year period before the ban. Crash rates did not decrease in very rural areas. Jacobson, S. H.; King, D. M.; Ryan, K. C.; and Robbins, M. J. 2012. Assessing the long term benefit of banning the use of hand-held wireless devices while driving. Transportation Research Part A: Policy and Practice 46(10):1586-93.

A 2011 study examined insurance claims filed for damage to vehicles before and after driver texting bans were enacted in four states. There was no reduction in claim rates relative to comparison states. Rather, there was a significant increase of 7-9 percent in three of the four study states. Increases in claim rates also were found for drivers 25 and younger in these three states. Trempel, R. E.; Kyrychenko, S. Y.; and Moore, M. J. 2011. Does banning hand-held cell phone use while driving reduce collisions? Chance 24(3):6-11.

It’s not clear why bans are not markedly reducing crashes despite reductions in hand-held phone use and texting while driving. Further research is needed in order to fully understand this disparity.

12 Can technology be used to reduce crash risks related to distracted driving?

Automakers are integrating "infotainment" systems into vehicles to let drivers and other occupants plug in or wirelessly connect portable electronic devices such as cellphones or MP3 players to vehicle entertainment and communication systems. Some of these systems allow drivers to interact with portable devices and other vehicle systems  using voice commands. Several studies have shown that using voice commands to interact with a portable device connected to a vehicle infotainment system reduces distraction but does not eliminate it. Ranney, T. A.; Harbluk, J. L.; and Noy, Y. I. 2005. Effects of voice technology on test track driving performance: implications for driver distraction. Human Factors 47(2):439-54. Owens, J. M.; McLaughlin, S.B.; and Sudweeks, J. 2010. On-road comparison of driving performance measures when using handheld and voice-control interfaces for mobile phones and portable music players. Paper No. 2010-01-1036. SAE 2010 World Congress & Exhibition. SAE International: Warrendale, PA. Owens, J. M.; McLaughlin, S. B.; and Sudweeks, J. 2011. Driver performance while text messaging using handheld and in-vehicle systems. Accident Analysis & Prevention 43(3): 939-47.  NHTSA has proposed voluntary guidelines for integrated infotainment systems in an effort to minimize the distraction potential of these systems. Office of the Federal Register. 2012. National Highway Traffic Safety Administration. Docket no. NHTSA-2010-0053 - Visual manual NHTSA Driver Distraction Guidelines for in-vehicle electronic devices. Federal Register, vol. 77, no. 80, pp. 24764-66. Washington, DC: National Archives and Records Administration.

Phone applications that restrict or limit access to electronic devices also have been developed. These apps aim to reduce device use by silencing the phone, redirecting incoming calls to voicemail or automatically responding to text messages with a preprogrammed message while a vehicle is in motion.

Crash avoidance technology is another promising avenue for reducing crash risk related to distracted driving. This technology can use warnings to redirect a distracted driver’s attention back to the roadway if it detects the potential for a collision.  These systems can even attempt to avoid the collision altogether if a distracted driver does not respond fast enough or does not respond at all.

See Q&A: Crash Avoidance Technology