248 N.Y. 339, 162 N.E. 99 (1928).

The plaintiff, Helen Palsgraf, was waiting for a train on a station platform. A man carrying a package was rushing to catch a train that was moving away from a platform across the tracks from Palsgraf. As the man attempted to jump aboard the moving train, he seemed unsteady and about to fall. A railroad guard on the car reached forward to grab him, and another guard on the platform pushed him from behind to help him board the train. In the process, the man's package, which (unknown to the railroad guards) contained fireworks, fell on the railroad tracks and exploded. There was nothing about the package to indicate its contents. The repercussions of the explosion caused scales at the other end of the train platform to fall on Palsgraf, causing injuries for which she sued the railroad company. At the trial, the jury found that the railroad guards had been negligent in their conduct. The railroad company appealed. The appellate court affirmed the trial court's judgment, and the railroad company appealed to New York's highest state court.

The New York Court of Appeals dismissed Palsgraf's complaint. The conduct of the railroad employees may have been negligent toward the man with the package, but it was not negligent in relation to Palsgraf, who was standing far away. The railroad was not negligent toward her because her injury had not been foreseeable. “Nothing in the situation gave notice … of peril to persons thus removed. … [No] hazard was apparent to the eye of ordinary vigilance … with reference to her.” The court stated the principle as “the risk reasonably to be perceived defines the duty to be obeyed.” To rule otherwise “would entail liability for any and all consequences, however novel or extraordinary.”