To sneak an extra half dozen into the drive-in? Sure. But a longer ride than that? I did look though and there are a couple more stories referencing this "trunking" practice. (the urls after the first)

Personally I'm not a fan of expanding restricted licenses, yet at the same time I didn't expect this sort of nonsense.

New Law Has Some Teens Riding Dangerously

(CBS13) A new state law now requires teens to have a provisional license for a year before anyone under 20-years old can hop in their car. Teenagers have found their way around this rule, like they have other laws.

Hiding in the trunk of cars, or what some teens have called 'trunking'.

So now firefighters are being trained to look out for this any accident from a fender bender, to a mulit-car pile up. Firefighters are checking the trunk.

Not all teens are taking the backseat, but for those who do, whether it's a weekend party or just out of a school parking lot, firefighter say they don't want any teen to see a chainsaw ripping into car, from the inside of a trunk.