Effect of Florida’s graduated licensing program on the crash rate of teenage drivers

Abstract

On 1 July 1996, Florida instituted a graduated licensing program for drivers younger than age 18. For the first 3 months, holders of learner’s licenses are not allowed to drive at all between 19:00 and 06:00 h; thereafter, they may drive until 22:00 h. Learner’s licenses must be held for 6 months prior to eligibility for the intermediate license. Sixteen-year-old intermediate license holders are not permitted to drive unsupervised from 23:00 to 06:00 h, 17 year-olds from 01:00 to 06:00 h. All drivers younger than 18 have strict limits on the number of traffic violations they can accumulate and, effective 1 January 1997, all drivers younger than 21 are subject to a zero tolerance law for drinking and driving. Florida crash data for 1995–1997 were obtained and compared with similar data from Alabama, a state that borders Florida but does not have graduated licensing. For 15, 16, and 17 year-olds combined, there was a 9% reduction in the fatal and injury crash involvement rate in Florida during 1997, the first full year of graduated licensing, compared with 1995. On a percentage basis, crashes declined most among 15 year-olds, followed by 16 year-olds and then 17 year-olds. Reductions were not seen among Alabama teenagers nor among 18 year-olds in Florida.

Introduction

Crash rates of young drivers on a per-mile basis are four to eight times higher than those of older drivers (Massie and Campbell, 1993). Both immaturity and lack of driving experience have been implicated (Mayhew and Simpson, 1990). In response, a number of states have begun to replace traditional licensing methods that typically allow quick and easy access to a driver’s license with a graduated licensing approach.

Graduated licensing is a system in which driving privileges are phased in, allowing initial experience to be gained in situations of lesser risk. The core provisions of graduated licensing include a required period of practice driving under the supervision of an experienced licensed driver and then an intermediate driving phase during which the young person is prohibited from unsupervised high-risk driving, e.g. late at night. Also, convictions for alcohol or other traffic violations during the intermediate phase can delay full-licensure status. Other possible provisions are a restriction against carrying teenage passengers and a requirement for two-stage driver education to coincide with the learning and intermediate phases.

The prohibition against unsupervised night-time driving during the intermediate license phase, other than for work or school, is of particular importance. Night driving restrictions have been shown to be highly effective in reducing teenage driver crash involvements. Reductions in fatal crash involvements nationally have been shown by comparing states with and without such restrictions (Levy, 1988) and for selected cities (Preusser et al., 1993). Reductions in nonfatal injury crashes also have been found for selected states (Preusser et al., 1984) and cities (Preusser et al., 1990).

Some elements of graduated licensing first were studied in the United States as part of a demonstration project in Maryland that began in 1979. Among its features were a provisional license that prohibited late-night driving and delayed full licensure if certain traffic convictions occurred. Results of the demonstration showed a 5% crash reduction among 16- and 17-year-old drivers (McKnight et al., 1983). In 1987, New Zealand adopted a graduated licensing system that includes a learning phase of 3–6 months followed by a 9–18 month intermediate license phase. During the intermediate license phase, the novice driver is prohibited from unsupervised nighttime driving, unsupervised carrying of passengers, and driving after consumption of even small amounts of alcohol. Evaluation of the New Zealand program was confounded by population declines among young people and economic recession. Nevertheless, motor vehicle injury reductions of 7% or more have been credited to this graduated licensing approach (Langley et al., 1996).

Ferguson et al. (1996) used different licensing practices in five contiguous Northeastern states to evaluate the effectiveness of various provisions of graduated licensing. Results showed that teenage driver crash rates were lower in states that restricted unsupervised driving by 16 year-olds, including night-time driving, than in those states that allowed unrestricted licensing of 16 year-olds.

In 1993, Louisiana began requiring 15 year-olds to complete 36 hours of driver education before becoming eligible for a driver’s license. Ulmer et al., (1999) found that this requirement reduced by one-third the number of 15 year-olds becoming licensed and reduced their fatal and injury crash involvements by as much as 20%. The delayed licensure of 15 year-olds also was found to enhance the effectiveness of a preexisting night driving restriction.

On 1 July 1996, Florida became the first state to adopt the main elements of a graduated licensing system, including a lengthy required learning period followed by an intermediate licensing phase during which unsupervised nighttime driving is prohibited (see Table 1). Also, traffic violations during the intermediate phase can lengthen the time needed to obtain a full-privilege license. In addition, on 1 January 1997, Florida adopted a zero tolerance statute applicable to drivers younger than age 21, prohibiting them from driving with a blood alcohol concentration of 0.02% or more. Sixteen and 17 year-olds who already had learner’s or driver’s licenses at the time of the new law also were subject to the night driving restriction, traffic conviction, and zero tolerance provisions. Florida therefore offers the first opportunity to evaluate a full graduated licensing system in the United States. The present study was undertaken to examine the effects of the law on the crash rates of Florida’s teenage drivers.