In the usual case of negligence an award for damages is given according to the foreseeability of the injury which occurred. In such instances a person is not guilty of negligence unless the harm that occurred was reasonably foreseeable given the negligent act. For example, in Abrams v. City of Chicago, 811 N.E. 2d 670 (Ill. 2004), a woman who was in labor with her contractions 10 minutes apart called 911 to have an ambulance transport her to the hospital. Since the contractions were so far apart the operator instructed her that an ambulance was not necessary and to have someone drive her to the hospital. On the way, they were hit by a car and the baby was killed. Neither the hospital nor the 911 operator were liable since the accident was not reasonably foreseeable. However, there are situations when the injury is outside the scope of foreseeable risk but the negligent party may still be held liable.

The “eggshell rule” addresses this scenario. It gets its name from a situation in which a person was injured by a falling object only because he had a thin, “eggshell,” skull. Let us imagine a situation in which the “eggshell rule” may provide relief. Suppose there is a man who has a bone spur on the inside of his spinal cavity in the middle portion of his neck. This condition is not visible by any outward manifestation but is extremely dangerous since the spur is impinging on the spinal cord. Now let us imagine that he was negligently hit in the back of the neck while he was shopping at the local lumber store when he bent down to pick up a quarter he dropped and a piece of wood fell off the shelf and hit him on the back of the neck. It was not a large piece of wood and would normally not have resulted in an injury. In this case, however, it causes instant paralysis from which there will be no recovery. Now we have a man who is paralyzed from the neck down and confined to a wheelchair for life. This is an obvious case of negligence because a piece of wood should not just fall off the shelf. But, is it foreseeable that a man would be paralyzed by this simple negligent act? Probably not. But does that mean the defendant should not be held liable? If he is not liable, who should bear the cost to the now handicapped man? In our example the man would not have been injured by this simple but negligent act had he not had the previous neck condition. However, he did have the condition and was paralyzed and the defendant is now responsible for the entire injury. The negligent actor is stuck with the victim as he finds him. For this reason the “eggshell rule” was adopted and is still in use today.