Research In Action
Research In Action
As states consider whether to improve existing Graduated Driver Licensing (GDL) provisions or to extend current requirements to include older novice driver populations, it is critical for the research community to provide rigorous scientific evidence. Seeing the need, I recently published a conceptual analysis of the issues and review of the existing evidence involved in extending GDL to older novice drivers in collaboration with Robert D. Foss, PhD, of the Highway Safety Research Center at the University of North Carolina at Chapel Hill, and Allan F. Williams, PhD, and with support from State Farm Mutual Automobile Insurance Company.
Key Points to Share With Policymakers
- There is solid evidence that appropriately calibrated GDL provisions result in substantial crash reduction among the youngest novice drivers.
- Currently 36 states have a nighttime limit that begins at 11 pm or later—even for the youngest drivers. This is too late to produce the intended benefit of protecting novices from the most risky driving condition as they begin driving without adult supervision. Approximately 60 percent of all nighttime crashes among young novice drivers occur from 9 pm to 11 pm.
- Further understanding of older novice drivers’ crash risks across different jurisdictions, as well as how their driving patterns, travel needs, and support systems differ from those of the youngest novice drivers, is urgently needed. These data would provide important evidence on whether the US GDL approach—which was originally designed for high school aged teens—is logistically feasible for, acceptable to, and able to produce similar benefits among older novice drivers.
Currently NJ has provided the best opportunity to study this important topic. NJ is only one of three jurisdictions in the US that apply full GDL rules, including nighttime and passenger restrictions, to all novice drivers under age 21. With funding support from the AAA Foundaton for Traffic Safety, I recently published a study with colleagues in Accident Analysis and Prevention that provides new findings to help inform the debate.
Using the New Jersey Traffic Safety Outcomes (NJ-TSO) Data Warehouse, we conducted a longitudinal analysis of more than 1 million novice drivers in NJ who got licensed from January 2006 through December 2014 to compare crash rates of older and younger novice drivers over the initial four years of licensure. Roughly, two-thirds were licensed at age 17, 16 percent were licensed from the ages of 18 to 20, another 5 percent were licensed at age 21 to 24, and 10 percent were licensed at age 25 or older.
- Study findings suggest NJ’s current GDL policy is making 17- to 20-year-olds safer.
- Conversely, there was a lack of compelling evidence for additional policies for drivers licensed at age 21 to 24 and no evidence to indicate a need for additional GDL policies for NJ novice drivers age 25 years and older.
To provide further evidence to inform extending GDL to older novice drivers, research in other states that have recently extended some GDL requirements to older novice drivers is urgently needed.