1.5 GDL Cell Phone Restrictions

Overall Effectiveness Concerns: The effectiveness of this widely used countermeasure has been examined in a few research studies. Despite some positive research findings, the balance of evidence regarding countermeasure effectiveness remains inconclusive.

As discussed in the Distracted Driving chapter, Section 1.2, young drivers are at a greater risk of crashing when they engage in distracting behaviors (Ferguson, 2003; Klauer et al., 2014). Specifically, with regard to cell phone use, young drivers are at higher risk of crashing when they reach for cell phones, dial cell phones, or text while driving compared to when they do not engage in these behaviors (Klauer et al., 2014). In one study the use of cell phones was associated with significantly longer response times (including no response, measured in seconds) than when drivers were not engaged in any cell phone use (2.8 s versus 2.1 s) (Carney et al., 2016). Drivers operating or looking at cell phones had longer response times than those engaged in phone calls (3.4 s versus 2.8 s), and they were more likely to make no evasive responses before collision compared to drivers engaged in conversations with passengers. Generally, the use of cell phones was associated with significantly longer eyes-off-road duration (4.1 s versus 0.9 s) and significantly longer response times (3.4 s versus 2.1 s) than when drivers were not distracted. These results further show the need for interventions that curb cell phone use by young drivers. A growing number of States include cell phone restrictions in their GDL laws. See the Distracted Driving chapter, Section 1.2 for a discussion of cell phone laws applying to all drivers.

Use: As of September 2019 there were 38 States and the District of Columbia that prohibit cell phone use for young drivers. These bans cover all cell phone use, not just handheld phones. In some States the cell phone restrictions cover teenagers holding learner permits and intermediate licenses; in other States, the restrictions cover all drivers under a certain age such as 18 or 19 (GHSA, 2019a). Twenty States and the District of Columbia prohibit handheld cell phone use for all drivers. In addition, 48 States and the District of Columbia prohibit text messaging for all drivers. One of the 2 States without cell phone bans prohibits text messaging among novice drivers (see the Distracted Driving chapter, Section 1.2).

Effectiveness: There is conflicting evidence regarding the effectiveness of cell phone restrictions on young drivers’ phone use and crash outcomes (McCartt et al., 2014; Delgado et al., 2016). See also Ehsani et al. (2016) for a review of research published in 2014 or earlier. Ehsani et al. conclude that cell phone restrictions may not result in a long-term deterrence of cell phone use by young drivers. Part of the reason for the lack of consistent evidence is the methodological differences among the  studies. The authors highlight the need for future analysis to distinguish between novice (e.g., early stages of driving, 16 or 17 years old) and more experienced young drivers and to include distraction-affected crashes as an outcome measure.

Cell phone restrictions do not seem to reduce young drivers’ phone use. One study examined the prevalence of distracting behaviors, including cell phone use, among drivers 16 to 19 years old enrolled in teen driving programs and involved in 412 rear-end crashes (Carney et al., 2018). The crashes occurred from August 2007 to July 2013 in Arizona, Colorado, Illinois, Iowa, Minnesota, Missouri, Nevada, and Wisconsin. Except Missouri and Nevada, these States have some form of ban on young driver cell phone use (GHSA, 2019b). In the 6 seconds before collision, drivers were most often using cell phones (18% of all distracting behaviors before rear-end crashes). Some 95% of these behaviors were coded as “operating/looking at phone” and included actions such as texting. A 2009 study examined the short-term effects of a teenage driver cell phone restriction in North Carolina and found that 5 months after a ban on cell phones took effect, the proportion of teens using cell phones while driving was unchanged (Foss et al., 2009). A follow-up study evaluated the long-term effect of North Carolina’s cell phone restriction 2 years after the law went into effect (Goodwin et al., 2011). Teenagers were observed at high schools in North Carolina and South Carolina, which did not have a cell phone restriction. In both States, there was a decrease in cell phone use. However, the decrease in cell phone use did not significantly differ between the two States, despite increased awareness of the restriction among licensed teens in North Carolina.

Some studies have examined the effects of cell phone bans on young-driver crashes. The outcomes provide inconclusive evidence of the effectiveness of cell phone restrictions. The HLDI conducted two studies to compare the collision claims of drivers 25 or younger in a few States with some form of cell phone restrictions relative to control States without these restrictions (HLDI, 2009, 2010). There were no significant differences in the collision claims of young drivers in States with handheld cell phone restrictions as compared to control States. However, collision claims of young drivers were found to increase 5% to 11.5% in States with texting restrictions relative to control States, perhaps as the result of concealing phones from view to avoid fines (HLDI, 2010). The outcomes from Ehsani et al. (2014) follow similar trends. They examined the effects of Michigan’s universal texting law on crash types among 16- and 17-year-old drivers and found a slight increase in the more serious crashes including fatal/disabling injury crashes and non-disabling injury crashes. However, they found a slight decrease in less severe crashes (e.g., possible injury/property damage only crashes). A study by Lim and Chi (2013) provides contradictory findings. Lim and Chi (2013) examined the relationship between cell phone bans and fatal crashes among drivers 20 and younger. They compared States across the United States that had no cell phone restrictions, cell phone restrictions that applied only to young drivers, and cell phone restrictions that applied to all drivers regardless of age. They found that cell phone restrictions that applied to all drivers regardless of age were associated with decreases in fatal crashes among young drivers. However, States that had cell phone restrictions that only applied to young drivers had no significant effect.

Delgado et al. (2016) suggest that a multi-pronged approach consisting of legal bans, HVE, increased financial and legal penalties, and greater parental involvement will be more effective in preventing phone-related distractions of young drivers.

Costs: Once GDL is in place, a cell phone restriction can be implemented at very little cost.

Time to implement: GDL requirement changes typically require about 6 months to notify the public and implement the changes.