Center for Injury Research and Prevention

GDL Compliance and Enforcement During Intermediate License Phase

Graduated Driver Licensing (GDL) programs -- which include limitations on passengers and nighttime driving restrictions during the first year of licensure -- are a cornerstone of public policy aimed at reducing the burden of crashes on adolescent health. Further reductions in teen crash rates will rely on strengthening specific provisions of GDL, as well as greater compliance with and enforcement of GDL provisions during the intermediate license phase. Thus, this program of research on GDL compliance and enforcement during the intermediate license phase led by Allison E. Curry, PhD, MPH has focused efforts to inform how best to improve GDL policy.

In a study published in the American Journal of Preventive Medicine, CIRP researchers reported the first population-level estimate of compliance with GDL among young drivers with an intermediate license. Using a novel application of the quasi-induced exposure technique, a method that has been developed to estimate driving exposure in the absence of more detailed information, the researchers determined rates of compliance with two GDL provisions—passenger limits and nighttime driving. This unique approach complements other current methods like naturalistic studies and paves the way for accurately measuring and improving GDL compliance and enforcement in the future.

For this study, the research team linked New Jersey’s licensing and crash record databases (July 2010 through June 2012), looking at data from 32,203 drivers and 30,594 crashes. They then focused on non-responsible crash-involved intermediate drivers to determine rates of compliance with two GDL provisions—passenger limits and nighttime driving.

Key Compliance Results

  • On the vast majority of trips, drivers with an intermediate license in New Jersey comply with the passenger and nighttime restrictions of the state’s GDL program.
  • More than 91 percent of young driver trips follow the state’s passenger restriction.
  • Nearly 97 percent comply with the nighttime restriction.

Although most young driver trips comply, 30,000 to 40,000 trips per day are still not in compliance with the passenger restriction and over 15,000 trips per day are not in compliance with the nighttime restriction, suggesting further work is needed to improve compliance. (Access the infographic on this page to learn more.)

Key Enforcement Results

  • The proportion of crash-involved drivers with an intermediate license that did not follow the restrictions who were issued a GDL citation was low (10.3 percent for non-responsible drivers and 19 percent for responsible drivers).
  • Enforcement rates were also highest among the youngest drivers: 18 percent of 17-year-old drivers known to be non-compliant with the GDL passenger restriction were issued a citation compared with 3 percent of 19-year-olds.

Read a blog post about the research.

View an infographic about the research.

Principal Investigator: Allison E. Curry, PhD, MPH; Funding: Eunice Kennedy Shriver National Institute of Child Health and Human Development at the National Institutes of Health