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VI. Negligence: The Standard of Reasonable Care

We now shift gears away from intentional wrongdoing and its defenses and toward what many consider to be the heart of tort law, both in volume of cases (and damages) and in conceptual challenge: negligence. Under what circumstances should someone’s actions be deemed careless enough to warrant damages, while falling short of the level of riskiness (or even certainty) of harm associated with intentional tort? At the core of negligence is a deceptively simple-sounding standard: to behave reasonably.

In order to determine whether a party has satisfied the cause of action for negligence, courts examine five factors: whether the defendant owed a duty to the plaintiff; whether that duty has been breached; whether the defendant’s breach of duty caused the harm; whether “proximate cause” is satisfied, and whether cognizable harm has accrued. Duty, breach, cause, proximate cause, and harm. Each element poses interesting and unique questions. Among them: what factors lead a relationship to entail a heightened duty by one person to act in a way that takes account of the interests of another person? How do we unpack the standard of care needed to breach that duty? Must we only consider physical harm? And how many links from an upstream act to a downstream act may there be before we call into question causation? Torts students for time immemorial have asked themselves these questions.  

Negligence law naturally draws in a group of defendants rarely seen in intentional tort: corporations. Can a standard of reasonableness be as intuitively grasped by a jury for judgment of a firm’s behavior as for a person’s actions? How much of the application of that standard should be left to a jury, and how much to a judge, who can decide whether a fact pattern — even one most sympathetic to a plaintiff — merits a jury’s look at all?

The cases in these sections look at how the law conceives of a negligence standard by examining cases in which judges had to decide whether a jury should hear the case — or, if a jury heard it, whether they applied the negligence standard correctly. Included is a case famed among legal scholars but typically unremarkable to senior practitioners: U.S. v. Carroll Towing. Carroll Towing introduces a formula by which one judge thought negligence might be further fleshed out — “unreasonable” behavior unpacked. How helpful is Judge Hand’s formula of “b < pl”? When, if ever, should a jury be exposed to it? Are there elements of unreasonable behavior not always captured by those three variables?