The Eggshell rule
Understanding the Law
August 23, 2019
The Eggshell rule

EGGSHELL SKULL or thin skull rule is a well-established legal doctrine in criminal law, as well as tort. The rule is on the side of a victim harmed by the defendant. It draws attention to a person’s frailty or weakness and compares it to an “eggshell’. Eggshell is delicate, brittle and easy to break. Where a victim has certain frailty, weakness or feebleness or an eggshell skull and is harmed by another, he would be awarded damages even if the tortfeasor is unaware of the victim’s condition.

The defendant cannot use the defense that a person’s conditions should relieve him from damages. The tortfeasor is liable for all the consequences of not only his negligent action, but for the aggravation of the condition of the victim. However, the rule does not seek to put the claimant in a better position than his original position. The defendant is liable for the additional damage caused by his negligent action.

If a defendant commits a minor assault on a person with a heart condition and the victim dies of a heart attack, the defendant is liable, even though an ordinary victim might not have died. Where a person with a vulnerable condition dies from the effect of the act of another, then that defendant would be liable.

Where there is a pre-existing condition that would worsen over time it may be viewed as a crumbling skull. The thin skull rule must not to be confused with the “crumbling skull rule”, which refers to a condition, which would have naturally worsened over time. The defendant would only be liable to the degree the injury was worsened or the acceleration of the damage caused by the tortfeasor.

The thin skull rule takes into account the social, physical and economic characteristic of the plaintiff and including family environment.

In criminal law the maxim, “take a victim as you find him”, is often used. In other words one cannot separate the victim from his condition and the defendant must take responsibility for his action. In the case, R v Blaue (1975) 1WLR 1411 Court of Appeal (England and Wales), the facts show that the defendant entered the home of an 18-yearold and stabbed her four times after she refused his advances for sex. She was seriously wounded, but because she was a practising Jehovah’s Witness and she refused blood transfusion, she died as a result of loss of blood. The medical evidence showed that she would have lived if she had received the blood. The crown showed that the refusal to have the blood caused her death.

The defence argued on the basis of “novus actus interveniens”, (intervening cause), claiming that the refusal to accept medical treatment broke the chain of causation between the stabbing and her death.

Lord Lawson explained that the defendant could not blame the victim for her refusal of a blood transfusion. He did not

accept that this was “novus actus interveniens” (intervening cause) and ruled that as a matter of public policy, “those who use violence on others must take their victims as they find them”. The defendant’s conviction of manslaughter was upheld.

The eggshell skull, thin skull principle, is used in a wide range of torts including intentional tort, negligence and strict liability. There does not have to be personal contact. It is not easy to apply the rule in cases beyond physical injuries. Traumatic injuries are not easy to prove because they are invisible and difficult to measure.

It is also difficult to award damages for pre-existing conditions.

Ada Johnson is a solicitor and barrister-at-law.