Does graduated driver licensing reduce drinking and driving? : an examination of California's teen driving restrictions.

In July 1998, California passed one of the U.S.'s toughest graduated driver licensing (GDL) laws. This study evaluates the effect of the state's GDL provisions-a strict teen passenger restriction and nighttime driving limitation-on alcohol-related crashes. While prior studies do not clearly demonstrate that GDL leads to alcohol-related crash reductions among teens, results in California show sharp reductions in had been drinking crash rates of 16-year-olds, especially in comparison to crash rates for a control series of 19-year-old drivers. The reduction in the had been drinking driver crash rate (per 100,000 drivers) for 16-year-olds from pre-GDL to one year post GDL is 16.0%; during the second post GDL year, it is 13.1%. When crash rates are standardized to control for crash trends of 19-year-olds, reductions are 21.0% and 22.0% in post GDL periods. (Author/publisher) For the covering abstract of the conference see ITRD Abstract No. E201067.