Negligent infliction of emotional distress (NIED) is a personal injury claim, cause of action, or tort (wrongful act) that is recognized in some states. NIED claims seek to hold another person or entity civilly liable (for money damages) caused by careless or negligent conduct that causes mental or emotional damage (severe emotional distress) to the injured claimant or plaintiff.

Some states that recognize an NIED claim have additional requirements that the claimant or plaintiff suffered a physical injury or was “in the zone of danger” created by the negligent conduct, for example.

And in many states there is no recognized cause of action or claim for the negligent infliction of emotional distress, and no general duty not to negligently inflict emotional distress. A claimant may recover mental anguish damages only in connection with defendant's breach of some other legal duty.

But some states, such as California, recognize an NIED claim by a direct victim as well as for a bystander who observed the negligent infliction of emotional distress. A bystander claim is often limited to close relatives of the direct victim.

Laws vary from state to state and the law regarding the tort of negligent infliction of emotional distress is often located in a state’s court opinions (also known as case law, common law, or judicial decisions).

In California, the tort of negligent infliction of emotional distress (NIED) is recognized and can be claimed by both direct victims and bystanders who witness the infliction of emotional distress. For direct victims, the claim arises when a person's negligent act or omission causes emotional or mental harm to another. California law does not always require a physical injury for an NIED claim, but the emotional distress must be serious and not trivial or transient. For bystander NIED claims, the claimant must be closely related to the injury victim, have been present at the scene of the injury, and have personally observed or perceived the injury. These requirements stem from the landmark case of 'Thing v. La Chusa' which established the criteria for bystander NIED claims in California. The specifics of NIED claims, including the standards for proving such claims, are largely derived from case law rather than statutes, and thus can be subject to interpretation and refinement by the courts over time.