Here's a gender-bender. New federal research says teenage drivers take more risks and drive more recklessly when other teenagers — particularly boys — are in the passenger seat. But boys become slightly safer drivers in the presence of a female companion. Perhaps more surprising was the finding that teenage girls took more risks when accompanied by either male or female passengers.

Researchers from the National Institute of Child Health and Human Development can't fully explain these findings. It could be that teen drivers tend to drive more recklessly to show off when they have a male front-seat passenger. Or perhaps the male passenger exerts pressure on the driver. Could it be that teen brains aren't fully developed, so they — male and female — take stupid risks they shouldn't?

If trained researchers can't tell us why, I hesitate to venture a guess why this is so. But it makes me glad for Utah's graduated drivers' licensing laws and hope for some refinements.

Utah's laws, which went into effect in recent years, have improved on-road safety of teenage drivers. Crashes involving 16-year-old drivers dropped 5 percent in the three years after the laws were changed. That's encouraging, but far less than the 20-30 percent reductions experienced in other states.

One explanation may be that Utah's laws are structured differently than those of other states, where driving violations are tied directly to license point systems. In those states, teens who violate traffic safety laws do not advance as quickly to the next level of privilege, en route to receiving a full license. Utah's laws are based on time, not the successful completion of various stages of a graduated license program.

Invariably, legislative debates over graduated driver licenses have rural-urban divisions. People who live in rural places balk at restrictions on driving because parents need their teens to be able to help with chores on farms and ranches.

I struggle with the rural arguments, because I grew up in a very rural place. Teens in rural places tend to drive more than their urban counterparts. Many drive roads that are more treacherous than their urban counterparts. Fewer and fewer teen drivers can legitimately claim an "agricultural-related work" exemption.

Urban lawmakers who live in more populated metropolitan areas recognize that they share the road with a greater concentration of teen drivers. If graduated driver licenses mean safer roads, it's good public policy.