Intentional infliction of emotional distress (IIED; sometimes called the tort of outrage) is a common law tort that allows individuals to recover for severe emotional distress caused by another individual who intentionally or recklessly inflicted the emotional distress by behaving in a way that was "extreme and outrageous". Some courts and commentators have substituted mental for emotional, but the tort is the same.
IIED was created in tort law to address a problem that would arise when applying the common law form of assault. The common law tort of assault did not allow for liability when a threat of battery was not imminent. A common case would be a future threat of harm that would not constitute common law assault, but would nevertheless cause emotional harm to the recipient. IIED was created to guard against this kind of emotional abuse, thereby allowing a victim of emotional distress to receive compensation in situations where he or she would otherwise be barred from compensation under the common law form.
According to the first doctrine articulated by common law courts, a plaintiff could not recover for physical injury from fright alone absent a physical impact from an external source ("shock without impact"), even if the fright was proven to have resulted from a defendant's negligence, with the case on point referring to the negligent operation of a railroad. Even with intentional conduct, absent material damage, claims for emotional harm were similarly barred. "Mental pain or anxiety, the law cannot value, and does not pretend to redress, when the unlawful act causes that alone. Though where a material damage occurs, and is connected with it, it is impossible a jury, in estimating it, should altogether overlook the feelings of the party interested." Courts had been reluctant to accept a tort for emotional harm for fear of opening a "wide door" to frivolous claims.
A change first occurred in the Irish courts which repudiated the English railroad decision. The idea that physical/mental shock without impact from an external source would be a bar to recovery was first questioned at the Queen's Bench in Pugh v. London etc. Railroad Co. In the following year, the tort was first formally recognised in the case of Wilkinson v. Downton [1897] 2 QB 57, although it was referred to as "intentional infliction of mental shock". Citing Pugh and the Irish courts as precedent, the Wilkinson court noted the willful nature of the act as a direct cause of the harm.
It is not necessary that an act be intentionally offensive. A reckless disregard for the likelihood of causing emotional distress is sufficient. For example, if a defendant refused to inform a plaintiff of the whereabouts of the plaintiff's child for several years, though that defendant knew where the child was the entire time, the defendant could be held liable for IIED even though the defendant had no intent to cause distress to the plaintiff.