New research out of Washington University suggests the answer is "yes" to our headline question - that laws restricting how late at night teens can drive or how many passengers they can have may also be keeping teens from driving drunk.
The study used data from 1999 to 2009 on teen drinking and driving in 45 states with graduated driving licensing laws.
Wash U. psychologist Patricia Cavazos-Rehg led the study. She says states adopted teen driving restrictions at different times, and that some states are stricter than others.
(To see how individual states compare in their teen driving restrictions, see the chart in the gallery above, and see more charts here).
She says Missouri only started restricting teen driving in 2007.
"We didn't specifically look at Missouri, but we can say that for those states with strict graduated driving licensing laws, we are observing a reduction in teen drinking and driving behaviors," Cavazos-Rehg said.
Cavazos-Rehg says the next step will be to determine what kinds of restrictions are most effective at keeping teens from driving under the influence.
"Is it the nighttime restriction, the passenger restriction, is it that teens are afraid of losing their drivers license?" Cavazos-Rehg said. "So we want to look more closely at what specific components of these laws are contributing to these reduced hazardous driving behaviors."
According to the US Centers for Disease Control and Prevention, a quarter of young drivers who died in car crashes in 2008 were driving under the influence.
- Missouri's graduated driving licensing law
- Missouri's use-and-lose law
- Illinois' graduated driving licensing law
- Illinois' use-and-lose law
- CDC fact sheet on teen driving
Follow Véronique LaCapra on Twitter: @KWMUScience