You may be familiar with signs that state that trucks need to stay in the right-hand lane. Is that a law, though, and if so, why do so many people violate it?
It certainly is irritating to see a truck driver in the left-hand lane, especially when it slows others down. Slower-moving vehicles in the left-lane are potentially dangerous to drivers. This is why slow-moving vehicles, and sometimes large trucks, are required to stay in the right lane and only use the left lane for passing.
When a slower vehicle is in the left lane, it causes all kinds of problems. The left lane is intended to be used for passing only. When a driver is there holding up traffic, traffic becomes backed up. Drivers become frustrated, and that's when road rage begins to become a problem.
Sometimes, truck drivers like to drive on the left to avoid slower-moving vehicles in the right-hand lane. Since they're passing, that's usually legal. On the other hand, if a truck driver won't move back over, he or she could slow down traffic in the left-hand lane as well. Now, two lanes are slowed down and traffic becomes congested and backed up. This makes conditions ripe for crashes, since drivers may weave around the trucks to try to avoid being slowed down by their presence.
On the whole, states either require or prefer larger and slow-moving vehicles to stay in the right-hand lane. Even if it's not illegal, it's still the kind and respectful thing to do. If you're hit by a driver who is negligent because of a truck driver or hit by the truck driver himself- or herself, remember that you have every right to pursue your claim.