Looked at logically, society takes a leap of faith in entrusting motor vehicles weighing several thousand pounds to drivers who are still growing in every way including good judgment. But at 16¹/₂ in Pennsylvania, a young motorist can get a junior license that puts him (or her) on the road without adult supervision.

It's a leap of faith that sometimes ends in tragedy -- and state Rep. Katherine Watson, a Republican from Bucks County, wants to reduce the chances of grief by toughening the requirements for drivers 16 and 17 years old.

It is a decent impulse. While the number of youthful deaths has actually fallen recently -- in 2004, for example, 21 drivers who were 16 died compared with 50 in 2003, according to PennDOT -- every one is a parent's worst nightmare and a terrible blow to individual communities. Rep. Watson thinks something more needs to be done to help teen drivers stay alive and unhurt.

She is preparing a bill that she intends to introduce in mid-April. While it is still a work in progress, one of the requirements would be a prohibition on a junior driver carrying more than one teenage passenger in the vehicle. As the Post-Gazette reported Monday, studies do confirm the risks associated with teenagers driving their friends around -- with the greater the number of passengers, the more the danger. Common intuition says the same thing -- because teens are notorious for egging each other on.

Such a rule might be inconvenient for some teens but an exception is contemplated for siblings, which seems reasonable. Another good proposal has to do with the number of hours that a teen needs to drive with a licensed driver who is at least 21 before taking the test.

Currently, a teen with a learner's permit at age 16 must have 50 hours of such experience over six months before taking the driver's test. Rep. Watson wants to increase that to 65 hours -- with 10 hours of that being devoted to driving at night under adult supervision and five hours driving in inclement weather.

Piling on is a danger in all this, because junior drivers are already limited to a large extent. They have an 11 p.m. curfew in most cases. They face tougher penalties for infractions than drivers with regular licenses (which are usually issued at age 18). A zero tolerance policy exists for any alcohol use -- as it should.

That is why we balk at the proposal that police be allowed to stop junior drivers who don't wear seat belts, when for everybody else the offense is a secondary infraction. Seat-belt use is important but so is fair play. How would officers even know who was a junior driver? This seems to be an invitation for some official fishing expeditions.

That said, the proposed bill has a lot of promise and deserves serious consideration. More can be done to reduce the terrible accidents that sear everyone. The trick is to make teen drivers more responsible without overreaching.