According to, teens are driving drowsy and falling a sleep at the wheel and parents may be contributing to that behavior, based on a new study by Liberty Mutual Insurance and Students Against Destructive Decisions.

In that study of 2,500 high school students from across the country, nearly one in ten of the licensed teens surveyed said they had fallen asleep while driving.  32 percent said they drive drowsy at least some of the time and more than half admitted to driving when they felt too tired to do their best.

One expert said, "probably the most compelling results from the study are the prevalence of some of these behaviors."