Taking another example, consider how toughening night driving restrictions could yield benefits. Iowa’s restriction begins at 12:30 a.m., while in South Dakota, the restriction starts at 10 p.m. If Iowa adopted an 8 p.m. restriction, teen fatal crashes would be reduced 10 percent.
There are no restrictions on teen passengers in either state. If Iowa and South Dakota both adopt bans on teen passengers for beginner drivers, the result would be a 21 percent drop in teen fatalities (among 15- to 17-year-old drivers) and a 5 percent drop in collision claim rates (among drivers aged 16 to 17).
But the best-case scenario is if both states toughen provisions across the board by implementing the best practices. South Dakota would realize reductions of 63 percent in fatal crashes and 37 percent in collision claims. Iowa could see a 55 percent fatal crash rate reduction and 29 percent in collision claims.
New online calculator measures effects of state GDL changes
The Institute and HLDI have developed an online calculator to estimate the effects of strengthening or weakening the five key GDL provisions on a state-by-state basis. The projections are based on results showing what matters most in preventing fatal crashes and collision rates among teen drivers.
The estimated percent reductions in teen driver fatal crashes and collision claims if states adopted the best GDL provisions ranges from 17 percent in Washington, D.C. and Connecticut to 56 percent in North Dakota (fatal teen crashes) and from 6 percent in Pennsylvania to 37 percent in South Dakota (collision claims).
Here are two examples of how individual states can significantly reduce teen crash fatalities and collision rates by adopting the best practice provisions.
- Alaska – Currently, Alaska has a permit age of 14, 40 hours practice hours, license age of 16, night driving restriction beginning at 1 a.m. and no teen passengers allowed. By raising the permit age to 16, increasing practice hours to 65, raising license age to 17 and imposing night driving restrictions beginning at 8 p.m., Alaska could see a 42 percent reduction in teen fatalities and 21 percent drop in collision rates.
- New York –Currently, New York has a permit age of 15, 50 practice hours, license age of 16 years, 6 months, night driving restriction starting at 9 p.m. and one teen passenger permitted. By implementing changes in four key provisions – increasing practice hours to 65, raising license age to 17, imposing an 8 p.m. night driving restriction and banning all teen passengers, New York could see a 24 percent reduction in fatal teen crashes and 7 percent reduction in collision claims.
See more information from the IIHS on young driver licensing systems in the United States, along with calculator methodology, click here.