Rates and predictors of teen driver crash culpability

Motor-vehicle crash risk is highest among teen drivers. Despite a wealth of research on the topic, there are still many contributors to these crashes that are not well understood. The current study sought to examine the contribution of graduated driver licensing (GDL) restrictions, sex, age, roadway circumstances, and citation history to teen drivers' crash culpability.

Crash system data from the Iowa Department of Transportation were linked with traffic-related charges from the Iowa Court Information System. Crashes involving teens aged 14 to 17 years between 2016 and 2019 were analyzed (N = 19,847). Culpability was determined using the driver contributing circumstances from the crash report. Moving and non-moving traffic citations issued prior to the date of each crash were considered. A multivariable logistic regression model was constructed to examine predictors of crash culpability.

Teen drivers were determined to be culpable for more than two thirds of crashes (N = 13,604, 68.54%). Culpability was more prevalent among males, younger teens, in rural areas, in the presence of reported roadway contributing circumstances, during hours of restricted nighttime driving, and among teens with citation histories that included both moving and non-moving citations. Similarly, multivariable model results indicated that the likelihood of culpability was higher among males, in rural areas, and at each stage of GDL compared to teen drivers with unrestricted licenses. While drivers with a history of both moving and non-moving violations were more likely to be culpable, those with a history of only moving or only non-moving violations were less likely to be culpable compared to those with no violation history.

Sex, crash location, and GDL stage were associated with teen driver crash culpability. A singular prior moving or non-moving violation may play a protective role in teen crash culpability.