Teen driver licensure provisions, licensing, and vehicular fatalities

Between 1996 and 2015, vehicular fatalities per capita involving 16- to 17-year-old drivers declined by 68.7%. During this same period, states enacted teen driver licensure provisions in an á la carte fashion, now collectively referred to as graduated driver licensing (GDL) programs, that restricted teen driving. While the literature demonstrates that 'good' GDL programs reduce vehicular fatalities, how these reductions occur remains open. In this study, separate GDL provisions and no pass, no drive laws are studied to understand reduction mechanisms. The evaluation is based on a state-by-year panel and uses difference-in-difference and triple-difference specifications to identify causal impacts on rates of licensing, vehicular fatalities, and fatalities per licensee. The empirical results find that the minimum intermediate licensing age of 16.5 or older provision reduces licensing of 16- to 17-year-old teens by 20.1%, and no other licensure provision consistently impacts licensing. In addition, vehicular fatalities decrease from the minimum intermediate licensing age of 16.5 or older provision by 22.7%, the driver's education reduces supervised hours provision by 5.9%, and no pass, no drive laws by 7.3%, while vehicular fatalities increase from the supervised driving hours required provision by 6.3%. Furthermore, only teen driver cellphone or texting bans have impacts on vehicular fatalities per 16- to 17-year-old licensed female and few long-term impacts are identified on those ages 18-20 who 'graduated' from licensing programs. This research suggests that GDL programs affect vehicular fatalities mostly through incapacitation, rather than programmatically.