A friend drives semi's for a living. His greatest annoyance is when people do this to his big-rig. In fact, car drivers will do the same thing to a gravel-hauler!

After the truck attempts to stop (with a braking distance far greater than even the worst of the cars out there) and runs out of room, hitting the vehicle in front, the truck's driver usually comes out worse. 18-wheelers don't yet have all of the built-in crash-resistance features and airbags of required of even the most basic cars.

The law usually insists that it was the truck's fault!