Did the CT Teen Driving Law Save Lives?

Authors: Ilya Ilyankou, Transport Hartford Ambassador and Anthony Cherolis, Transport Hartford Coordinator

In 2008, Connecticut introduced tougher laws for 16- and 17-year old drivers. The graduated driver’s license laws went into effect on August 1st, 2008 and included:

  • A two-hour joint parent-teen safety information class
  • Enhanced penalties, including fines and license suspensions for violations
  • Prohibition of cell phone use while driving, even hands free
  • Driving curfews and passenger restrictions

As shown in a prior article, teens and young adults have a much higher rate of fatal crashes than other ages. That spike in fatal crashes drops for both men and women in their late twenties. Laws that address high risk behaviors and reduce the number of inexperienced, immature drivers on the road are likely to reduce severe crashes and fatalities. Does that common sense prove effective?

First, we see that after the 2008 law was implemented, fewer age 16 and 17 obtained a driver’s license, a 15% reduction. That means that after the 2008 law was passed, there were fewer inexperienced drivers on the road.

Did these changes reduce the number of teen driver fatalities on the roads of Connecticut? We looked at the crashes that involved teen drivers aged 15-19 (data available from UCONN Crash Data Repository) and plotted the number of fatalities for 6 years before and after the law was introduced: years 2003-2008 and 2009-2014 respectively.  There was noticeable drop in the number of teen crash fatalities after the law was implemented.

The average number of teen driver fatalities between 2003 and 2008 was twenty per year, with the maximum of twenty four in years 2004 and 2007. The average number of teen driver fatalities in 2009-2014 was eleven, which is 47% lower than the average for the previous 6-year period. The maximum number of fatalities was in 2009 with fourteen young driver fatalities, which is the minimum of the previous six year period.

Now, to what extent can we say that it was the new teen driving law that helped the number of fatalities decrease? Let’s compare that with the numbers of drivers of all ages who ended up dead or seriously injured for the same time periods.  We know that after 2007 a reduction in US vehicle miles traveled occurred. Vehicle miles bottomed out in 2011 after a 3% reduction before beginning again to climb.  When there are fewer miles driven, we would expect fewer severe and fatal crashes. This is just one example of an external factor that could reduce crashes overall.  By comparing all ages to the isolated teen age group, we will see if the teen age group benefited from an even lower crash rate than that caused by common factors across all ages.

% Change In Driving Outcomes between 2003-2008 and 2009-2014

Category Description% Change for teens aged 15-19% Change for all ages
Drivers, Fatalities-47%-11%
Drivers, Seriously Injured-52%-30%
Passengers, Fatalities-45%-24%
Passengers, Seriously Injured-48%-36%

(click on % values in the table above for the full charts)

Yes.  All ages did show a decrease, but for all categories the much greater reduction in crashes was for teens aged 15-19. For example, the average annual number of teen drivers who ended up seriously injured in 2009-2014 was 52% below the value of 2003-2008, while drivers of all ages experienced only a 30% decrease.

So while the roads are becoming generally safer for all drivers and their passengers, teens experienced a much greater reduction in bad outcomes after the tougher teen driver laws were introduced.

Continuing this discussion – Should we keep making teen driving laws tougher until Vision Zero becomes a reality? What could be done to address the high crash fatality rate for drivers up into their mid-twenties, shown in the chart below? The European Union’s requirement to use GPS enabled speed limiters in all new cars seems like an effective safety improvement across all ages, including those risky years between 16 to 25.

Data, Resources, and Links