Keeping Teen Drivers Safe

When it comes to graduated driver licensing programs (GDLs), more means less: The more limits a GDL imposes on teenage drivers, the fewer fatal crashes they'll have. That's the finding of a recent study by the Bloomberg School's Susan Baker and colleagues, which appeared in the July issue of Pediatrics.

Graduated driver licensing programs, currently on the books in 36 states, are laws that dictate such criteria as the minimum age when a beginning driver can get a learner's permit, and that put restrictions on such things as nighttime driving and the number of passengers allowed. Some states' GDLs have more restrictions, some fewer.

The strictest graduated driver licensing programs decrease fatal crashes by about 20 percent, according to a new study by the Bloomberg School's Susan Baker.

When Baker, MPH '68, a professor of Health Policy and Management, and colleagues Li-hui Chen and Guohua Li, looked at data from all 36 GDLs in the United States, they found that the overall incidence of fatal crashes involving 16-year-old drivers was reduced in those states by an average of 11 percent. Further, they concluded that the most stringent GDLs—those that incorporate at least five of the seven components most commonly found in state systems—decrease fatal crashes by about 20 percent.

Still, Baker says the take-away lesson from the study involves more than statistics. GDLs can be difficult for the police to enforce: Unless a teen crashes or is driving erratically, the police aren't apt to stop those violating a GDL's conditions. This means, Baker emphasizes, that the parents of teen drivers must be the linchpins in any plan to reduce teen crashes.

"Sometimes parents of teens are so glad they won't have to drive their kids someplace, they're tempted not to check into the situation very thoroughly," says Baker, who founded the School's Center for Injury Research and Policy. "But parents need to be in close contact with each other so they're all in agreement as to who can drive, who and how many can be driven around, and under what circumstances."