One-third of US drivers are first licensed at age ≥18 and may differ from earlier licensees in important ways (e.g., socioeconomic status). Most US states’ Graduated Driver Licensing (GDL) policies apply only to novice drivers age <18. Four (of 51) US jurisdictions have extended GDL restrictions (nighttime, passenger) to older novice drivers; others are considering the appropriateness and feasibility of extending coverage as well.
To directly inform this discussion, we conducted novel analyses in New Jersey (NJ)—a state that applies GDL through age 20—and critically reviewed the evidence related to extending GDL restrictions.
We analyzed a unique linked database containing the licensing and crash history of all NJ drivers to estimate monthly per-driver rates of overall, nighttime, and multiple-passenger crashes for all novice drivers (license age 17; 18–20; 21–24; and ≥25). Additionally, we reviewed US and international literature to assess: the effect of extending GDL to cover older novices on crash rates; issues with compliance, acceptance, and enforcement; and evidence related to specific provisions.
Initial crash rates of novice NJ drivers first licensed at age ≥21 were substantially lower than those of novices licensed at age 17–20; further, novices licensed at age ≥21 experienced less steep crash reductions over the first year of licensure. Differences in crash reduction curves between periods covered by current NJ restrictions (11 pm–5 am) and earlier nighttime crashes (9 pm–11 pm) support a 9 pm starting time for nighttime restrictions for novice drivers licensed at age <20.
Collective evidence—including novel analyses conducted in NJ—suggests that drivers licensed at ages 18–20 would benefit from GDL restrictions limiting high risk exposure. There is a lack of compelling evidence for additional GDL policies for drivers licensed at age 21–24 and no evidence to indicate a need for drivers licensed at age ≥25.