Every day, between 4,000 and 8,000 crashes related to distracted driving occur in the United States. Despite the record drop in the 2009 national highway fatality rate, crashes in which distracted driving played a role are increasing, according to American Automobile Association (AAA) data. These types of collisions account for as many as half of the six million crashes reported in the U.S. annually, resulting in state initiatives to discourage the use of handheld devices while driving.    

Though cell phones are among the top distractions for drivers, the National Highway Traffic Safety Administration (NHTSA) includes eating, drinking, talking to passengers, interaction with in-car technologies, and use of portable electronic devices under secondary task involvement.

Drivers who use mobile phones while driving were four times more likely to crash than drivers who were not, a rate equal to that of driving while under the influence at 20 percent above the current nationwide 0.08 limit, according to a study from the New England Journal of Medicine.

However, studies show hands-free devices are not necessarily risk-free and distract drivers as much as handheld phones. The argument states it is the conversation that distracts the driver, not the handheld device.

States Quickly Adopting Legislation

State-proposed laws that target distracted driving are materializing quickly, with 11 laws taking effect in 2010 alone. State governments are quickly drafting new legislation to help deter the rising number of distracted driving-related crashes.

According to Federal Highway Administration (FHA) data, the 8.9 percent highway fatality rate drop is the lowest on record, showing that nationwide efforts such as the "Click it or Ticket" campaign may have proved beneficial. Increased awareness about the dangers of common distractions while driving might also help the fatality rate continue to drop in the future.

Primary laws that ban handheld cell phones for all drivers are currently enforced in California, Connecticut, New Jersey, New York, Oregon, Washington, and the District of Columbia. Delaware has signed similar legislation, effective Jan. 2, 2011.

Maryland enforces a secondary law that bans handheld cell phone use while driving. Utah has a secondary law under the broader term "careless driving," against committing a moving violation (other than speeding) while distracted by use of a handheld cell phone or other activities not related to driving.

Currently, 30 states and the District of Columbia have legislation in place banning text messaging for all drivers. Of the 30 states enforcing the ban, 23 states have a primary ban, four states have a secondary ban, and three states have legislation that have been signed but are not effective until the end of the year.

The difference between primary and secondary laws is noteworthy. Primary laws are stricter, stating drivers may be pulled over and cited if an officer sees them operating a cell phone while driving. In states with secondary laws, officers will pull over distracted drivers only if they are seen violating another primary law, such as speeding.

Approximately half of the states in the U.S. currently include a category for handheld or electronic equipment distraction on police accident report forms. However, recently proposed federal legislation would require all states to include this data to qualify for certain federal funding, according to the Governors Highway Safety Association (GHSA).

Most states allow local political subdivisions to enforce their own laws against distracted driving. However, Florida, Kentucky, Louisiana, Mississippi, Nevada, and Oklahoma have preemption laws that prohibit political subdivisions in their states from doing so.

Despite the fact that California and Oregon have strict primary legislation enforced, NHTSA observed more drivers in Western states operating handheld electronic devices than in other regions of the country. In 2008, use of handheld devices also increased the most in the Western states, rising from 0.6 percent in 2007 to 2.1 percent in 2008.

Characterizing Different Distractions

NHTSA categorizes driving distractions into three categories: visual, manual, and cognitive. Visual distraction involves actions that require the driver to look away from the road to obtain information visually. The use of handheld devices falls under manual distraction, which requires the driver to take one hand off the steering wheel and operate a device. Cognitive distraction occurs when the driver focuses on something other than driving, shifting mental weight away from safety.

The duration and/or frequency of engaging in any distracted driving task is directly proportionate with the crash-risk level involved, according to NHTSA data. The crash risk increases to a level comparable to a difficult task performed less often as the duration and/or frequency of the task increases.  

A 2008 NHTSA report found distracted drivers were 50 percent more likely to have been seriously injured or killed in crashes compared to attentive drivers. The report also showed that about 70 percent of distracted-driver crashes involved non-collision or rear-end crashes, with the remainder being mostly angle collisions.

Distracted drivers were also more likely to crash during the evening or night-time hours and less likely on high-speed roadways, multi-lane roadways, curves, and intersections. Drivers usually spend about 10 percent of the time looking away from the road when driving normally, compared to 40 percent while sending text messages.

Studies funded by the AAA Foundation for Traffic Safety found the effect of hands-free cell phone use on driver attention is comparable to tuning a radio. In addition, the studies found hands-free devices do not have an effect on other distractions that may be present in or outside of the vehicle, which have proven to be equally as distracting as cell phone use.