Teenage Crash Reduction Associated with Delayed Licensure in Louisiana

Abstract

Effective July 1, 1993, Louisiana added a provision to its driver licensing law that requires 15-year-olds to complete 36 hours of driver education before they obtain driver’s licenses. The subsequent crash experience of 15-year-olds in Louisiana was compared with that of 15-year-olds in Mississippi, which at the time of this study licensed at age 15; and experience in north Florida, which licenses at age 16. The effect of the new requirement was a 33% reduction in the number of licenses issued to 15-year-olds during the first full year following the law change. The fatal and injury crash involvements of Louisiana 15-year-old drivers declined by as much as 20% annually in the two years following the law change. Involvement rates of older teenagers in Louisiana as well as Florida and Mississippi remained unchanged or increased during the same time period. Louisiana’s night driving restrictions—applicable to drivers younger than age 17 and shown to be effective in previous research—were even more effective after the law change. Fatal and injury crash involvements during the restricted hours for 15- and 16-year-olds were, respectively, 51% and 27% lower than estimated involvements if the night driving restriction had not been in effect. The results of this study provide additional evidence that elements of graduated licensing systems, such as delaying the age of full licensure and night driving restrictions, are effective in reducing the very high rate of teenage involvements in serious motor-vehicle crashes.

Introduction

The rate of involvement of young people in serious motor-vehicle crashes is much higher than that of all but the most elderly drivers Massie et al. 1995, Williams et al. 1995. However, young driver crash rates vary considerably among states as a function of when and under what conditions teenagers become licensed (Preusser, 1996). Crash risks of 15–17-year-olds vary by more than 100% among states; the age at which practice driving is first allowed and the age at which licenses may first be issued are the most important factors in this variance.

Younger learning and licensing are associated with higher young driver crash rates (Table 1). In 1993, eight states and the District of Columbia prohibited practice driving before age 16 and licensed at age 16 or older; these jurisdictions had the lowest crash rates among 15–17-year-olds. Thirty-four states allowed practice driving before age 16 and licensed at age 16; these states had higher crash rates that increased with decreasing practice age. The remaining eight states, which allowed practice driving and licensed before age 16, had the highest crash rates Williams et al. 1996, Preusser 1996.

There is growing interest in the United States to examine the conditions under which young people become licensed, with graduated licensing systems being adopted or under consideration in several states. The purpose of graduated licensing is to phase in exposure to increasingly complex driving tasks and environments for young people as they mature and develop their driving skills. In such a system, beginning young drivers might have a learning period in which only supervised driving is permitted, a restricted period in which night driving is not permitted, followed by unrestricted licensure. New Zealand’s graduated licensing system is credited with reducing crashes among young drivers (Langley et al., 1996). In the United States, Ferguson et al. (1996) used differences occurring in licensing practices in five contiguous northeast states to evaluate the effectiveness of the possible elements of a graduated licensing system. Results showed that teenage driver crash rates were lowest in states with licensing practices, such as night driving restrictions, that came closest to the graduated licensing model.

Louisiana permits licensing at age 15. However, effective July 1, 1993, the state made it more difficult for 15-year-olds to quickly obtain licenses by adding a 36-hour driver education requirement, which includes 6 hours of on-road instruction. Although this program provides more instruction, it takes some time to complete and costs several hundred dollars. Alternatively, 15-year-olds can avoid this requirement by waiting until age 16 because the education requirement for 16-year-olds is a less costly 6-hour prelicensing course.

Louisiana also has had nighttime driving restrictions for drivers younger than 17 between 11 p.m. and 5 a.m. on Mondays through Thursdays and between midnight and 5 a.m. on Fridays through Sundays. Previous research shows these curfews have reduced crash involvements (Preusser et al., 1984).

The main objectives of this study are to determine if Louisiana’s new driver education requirement is associated with reductions in both the number of 15-year-olds who become licensed and the number of crash involvements of 15-year-old drivers. This study also examines the effect of the new requirement on this state’s night driving curfews.