Impact of Partial Graduated Driver’s License Program on Teen Motor Vehicle Crashes in Kentucky

Teen-driver motor vehicle crashes (MVCs), MVC-related injuries, and MVC-related costs before (1993-1995) and after (1997-1999) the implementation of the teen driver licensing (TDL) program in Kentucky are evaluated. Data collected as part of the study are used to recommend actions to enhance the effectiveness of Kentucky’s TDL program. The study involved the analysis of teen crash data pre-TDL and post-TDL by using data from the Kentucky Accident Reporting System database and the Kentucky Transportation Cabinet driver license file. The study also involved analysis of crash data in relation to crash costs by using the CrashCost software program. Findings indicate that implementation of the TDL program in Kentucky resulted in a substantial (32 percent) reduction in MVC rates for 16-year-old drivers from before the TDL program and a similar reduction in crashes after midnight, fatal crashes, and injury crashes for the 16-year-old age group. Cost analysis indicates an estimated annual reduction of $34.2 million in 16-year-old teen-driver MVC-related expenses. However, after a dramatic reduction in the number of crashes for ages 16 to 16.5 (learner permit stage), the number of crashes rose sharply for ages 16.5 to 17, when drivers may have progressed to independent driving. There were no decreases in crash rates for 17- and 18-year-old drivers under the TDL program. Results from this study indicate a need for more effective measures to decrease MVCs for ages 16.5 to 18, such as upgrading to a full graduated driver licensing program.