Torts Legal Terms Glossary
Key tort concepts covering negligence, intentional torts, and liability doctrines.
Definitions
Negligence
Negligence is a tort consisting of a failure to exercise the standard of care that a reasonably prudent person would exercise in a similar situation. A negligence claim requires four elements: duty, breach, causation (both actual and proximate), and damages. It is the most common basis for tort liability and contrasts with intentional torts and strict liability, which do not depend on the defendant's degree of care.
Duty of Care
Duty of care is the legal obligation to conform to a standard of reasonable conduct to protect others from foreseeable risks of harm. Whether a duty exists is a question of law for the court. The general rule is that everyone owes a duty to act as a reasonably prudent person under the circumstances. Special relationships, such as innkeeper-guest or common carrier-passenger, may impose heightened duties. Foreseeability of harm is the key factor in determining whether a duty exists.
Breach of Duty
Breach of duty occurs when a person fails to meet the applicable standard of care. Courts use the reasonable person standard — an objective measure of how a person of ordinary prudence would act under the same circumstances. The Hand Formula (B < P x L) is an influential economic approach: a party breaches their duty when the burden of precaution (B) is less than the probability of harm (P) multiplied by the gravity of the harm (L). Custom in an industry is relevant but not dispositive.
Proximate Cause
Proximate cause (or legal cause) limits liability to harms that bear a sufficiently close relationship to the defendant's negligent conduct. Even when the defendant's act is the actual cause of harm, liability may be cut off if the harm was too remote, unforeseeable, or attenuated. The Cardozo view focuses on foreseeability of the plaintiff, while the Andrews view focuses on whether the harm was a natural and continuous sequence from the defendant's act.
Actual Cause (Cause-in-Fact)
Actual cause, or cause-in-fact, establishes the factual link between the defendant's conduct and the plaintiff's injury. The standard test is the but-for test: but for the defendant's negligence, would the harm have occurred? When multiple actors contribute to an indivisible injury and the but-for test fails, courts may apply the substantial factor test. The burden of proof is on the plaintiff to establish actual causation by a preponderance of the evidence.
But-For Test
The but-for test is the foundational test for actual causation in tort law. It asks: but for the defendant's negligent act or omission, would the plaintiff's injury have occurred? If the injury would have happened regardless of the defendant's conduct, the defendant's negligence is not an actual cause. The but-for test can be difficult to apply in cases of concurrent causation or when multiple defendants are involved, prompting courts to use alternative tests such as the substantial factor test.
Res Ipsa Loquitur
Res ipsa loquitur ("the thing speaks for itself") is a doctrine that permits an inference of negligence when the accident is of a type that ordinarily does not occur without negligence, the instrumentality causing the harm was in the defendant's exclusive control, and the plaintiff did not contribute to the injury. It does not shift the burden of proof but creates a permissible inference that the jury may draw. The doctrine is particularly useful when direct evidence of negligence is unavailable.
Strict Liability
Strict liability imposes legal responsibility on a defendant without requiring proof of negligence or fault. It applies in certain well-defined contexts: abnormally dangerous activities, defective products (under Restatement (Second) of Torts Section 402A), and the keeping of wild animals. The policy rationale is that certain activities are so inherently risky that the party engaging in them should bear the cost of resulting injuries, regardless of the precautions taken.
Intentional Infliction of Emotional Distress (IIED)
IIED is an intentional tort that imposes liability when the defendant, by extreme and outrageous conduct, intentionally or recklessly causes severe emotional distress to another. The conduct must be beyond all bounds of decency tolerated in a civilized society. Mere insults, indignities, or annoyances are generally insufficient. Some jurisdictions require a physical manifestation of the distress, though this requirement has been relaxed in many courts.
Battery
Battery is an intentional tort involving the harmful or offensive contact with another person's body without their consent. The defendant must intend to cause the contact (or an imminent apprehension of contact), and the contact must be harmful or offensive to a reasonable person. The plaintiff need not be aware of the contact at the time. Battery is both a tort and a crime, though the elements and burdens of proof differ in civil and criminal proceedings.
Assault
Assault is an intentional tort involving an act that creates a reasonable apprehension of imminent harmful or offensive contact with the plaintiff's person. Unlike battery, assault does not require actual physical contact — only the apprehension of it. Words alone are generally insufficient; there must be an overt act. The apprehension must be of imminent contact, and the defendant must have the apparent ability to carry out the threat.
False Imprisonment
False imprisonment is an intentional tort that occurs when the defendant unlawfully confines the plaintiff within fixed boundaries without consent and without legal authority. The confinement may be accomplished by physical barriers, physical force, threats, or the assertion of legal authority. The plaintiff must be aware of the confinement or harmed by it. There must be no reasonable means of escape of which the plaintiff is aware.
Trespass
Trespass to land is an intentional tort involving the unauthorized physical entry onto or remaining on another person's real property. The defendant need only intend the act of entering — not intend to trespass — making mistake as to ownership no defense. Trespass protects the possessory interest in land and is actionable without proof of damages. It can also occur through causing a physical object to enter the land or by staying beyond the scope of permission granted.
Nuisance
Nuisance is a substantial and unreasonable interference with the plaintiff's use and enjoyment of their property (private nuisance) or with a right held in common by the general public (public nuisance). Unlike trespass, nuisance does not require a physical invasion — noise, odors, pollution, and vibrations can all constitute nuisances. Courts balance the severity of the interference against the utility of the defendant's conduct to determine reasonableness.
Defamation
Defamation is a tort involving the publication of a false statement of fact that harms the reputation of another. It encompasses both libel (written or recorded) and slander (spoken). The plaintiff must show that the statement was false, published to a third party, and caused reputational harm. Public figures must also prove actual malice — knowledge of falsity or reckless disregard for the truth — under New York Times v. Sullivan.
Libel
Libel is the form of defamation that occurs through a written, printed, or otherwise fixed medium, including publications, broadcasts, and online posts. Because of its permanent nature and wider potential reach, libel is generally treated as more serious than slander. At common law, libel is actionable per se — the plaintiff need not prove special damages. Modern applications extend libel to social media posts, blog articles, and other digital communications.
Slander
Slander is the form of defamation that occurs through spoken words or transient gestures. Unlike libel, slander generally requires proof of special damages — actual, quantifiable economic loss — unless it falls within the slander per se categories. Slander per se covers false statements imputing a serious crime, a loathsome disease, unfitness in one's business or profession, or serious sexual misconduct. In slander per se cases, damages are presumed.
Negligence Per Se
Negligence per se is a doctrine under which a court adopts a legislative or regulatory standard as the applicable standard of care. If the defendant violated a statute designed to protect the class of persons to which the plaintiff belongs against the type of harm the plaintiff suffered, the violation establishes breach of duty as a matter of law. The plaintiff must still prove causation and damages. Some jurisdictions treat the statutory violation as only a rebuttable presumption of negligence.
Comparative Negligence
Comparative negligence is a defense that reduces the plaintiff's recovery by the percentage of fault attributable to the plaintiff. Under pure comparative negligence, the plaintiff can recover even if more at fault than the defendant, minus their share. Under modified comparative negligence (the majority rule), the plaintiff is barred if their fault reaches 50% or 51%, depending on the jurisdiction. Comparative negligence has largely replaced contributory negligence in American jurisdictions.
Contributory Negligence
Contributory negligence is a common-law defense that completely bars the plaintiff from recovery if the plaintiff's own negligence contributed to the harm in any degree. This harsh all-or-nothing approach has been abandoned by most American jurisdictions in favor of comparative negligence. It survives in only a handful of states and the District of Columbia. The last clear chance doctrine developed as an exception, allowing a plaintiff to recover despite their contributory negligence if the defendant had the last opportunity to avoid the harm.
Assumption of Risk
Assumption of risk is a defense asserting that the plaintiff voluntarily encountered a known danger and, by doing so, implicitly consented to relieve the defendant of liability. Express assumption of risk occurs through a waiver or exculpatory clause. Implied assumption of risk arises from conduct showing voluntary acceptance of a known risk. In jurisdictions that have adopted comparative negligence, implied assumption of risk is often subsumed into the comparative fault analysis.
Vicarious Liability
Vicarious liability is a legal doctrine that imposes liability on one party for the tortious acts of another, based on the relationship between them. The most common application is respondeat superior, holding employers liable for torts committed by employees within the scope of employment. Vicarious liability does not require any fault on the part of the vicariously liable party. It serves the policy goal of placing the risk of loss on the party best able to absorb or distribute it.
Respondeat Superior
Respondeat superior ("let the master answer") is a specific form of vicarious liability that holds an employer liable for the torts of an employee committed within the scope of employment. The critical question is whether the employee was acting in furtherance of the employer's business at the time of the tort. A frolic (a substantial departure) takes the employee outside the scope, while a detour (a minor deviation) does not. Independent contractors generally do not trigger respondeat superior liability.
Joint and Several Liability
Joint and several liability is a doctrine that holds each defendant individually liable for the full amount of the plaintiff's damages, regardless of that defendant's proportionate share of fault. The plaintiff may collect the entire judgment from any one defendant, and that defendant must then seek contribution from the other defendants. Many jurisdictions have modified or abolished joint and several liability through tort reform legislation, replacing it with proportionate liability.
Attractive Nuisance
The attractive nuisance doctrine imposes a heightened duty of care on landowners with respect to artificial conditions on their property that are likely to attract trespassing children. Under the Restatement (Second) of Torts Section 339, a landowner is liable if the owner knows or should know children are likely to trespass, the condition poses an unreasonable risk of serious harm, children because of their youth cannot appreciate the danger, and the burden of eliminating the danger is slight compared to the risk.