Ban on overnight-hours passengers leads to fewer crashes, study of young drivers shows

West Lafayette, IN — When young drivers aren’t allowed to have passengers in their vehicle during overnight hours, crashes and related injuries go down significantly, according to researchers from Purdue University and the Max Planck Institute for Social Law and Social Policy in Germany.

In a recently published working paper, the researchers detail their examination of a ban – implemented in 2007 in New South Wales, a state in southwestern Australia that includes Sydney – in which driving with multiple passengers in the vehicle between 11 p.m. and 4:59 a.m. is prohibited for first-year drivers younger than 21.

The regulation, the researchers estimate, reduced reported hospitalizations and fatalities 58%. Overall, 41 fewer hospitalizations, 98 fewer minor injuries and 164 fewer crashes with property damage were reported per 100,000 first-year drivers.

The ban also seems to have a positive effect on driving behaviors, unlike some other restrictions, the release notes. That effect was more persistent among teens who started driving while the ban was in place.

The researchers note that although some restrictions reduce crashes, few lead to persistent behavioral changes. For instance, the effectiveness of speed-monitoring campaigns ceases when they conclude, while texting bans typically reduce crashes for only a month or two.

“We find significant reductions in nighttime multi-passenger crashes in the second and third years of driving,” Tim Moore, co-author of the paper and an associate professor of economics at Purdue, said in the release. “We see no differences beyond the third year, but by that time, teens have become much safer drivers – their crash rates are one-fifth of those of first-year drivers.”

The paper was published by the nonprofit National Bureau of Economic Research.