Also known as:forces of nature · act of God · vis major
Written by attorneys · grounded in primary & secondary sources — see below
An intervening natural event that may break the chain of proximate causation in a negligence action. The event qualifies as superseding when its operation is extraordinary and the resulting harm differs in kind from the risk that made the defendant's conduct negligent in the first place.
Sources & Authorities· 10 sources
Select any source to read its text and confirm it supports the definition.
Restatements
Casebooks
How it applies
Common Examples
6
Balcony Collapse During Rare Storm
Ocean Crest Resort installed lightweight balcony railings despite warnings they could fail in ordinary coastal storms. An exceedingly rare storm surge and high tide undermined the cliff and caused entire building sections to shear off onto beach restrooms below, injuring patron Maria. Maria sued the resort for negligence. The extraordinary natural event produced a different kind of harm than the guest falls the railings risked, relieving the resort of liability.
Accelerated Roof Collapse From Winds
A building owner negligently failed to repair a defective roof. Extremely high winds caused the roof section to crash down and kill a passerby. The owner argued the winds relieved liability. Because the winds merely accelerated harm that the defective roof would have caused anyway, the owner remained liable.
Birch Media allowed unsecured glass bottles in an upper balcony despite warnings about intoxicated patrons jostling there. An unprecedented localized downburst struck during a concert. The storm caused an intoxicated patron to drop a bottle from the balcony, injuring Norman below. The storm produced a balcony-to-ground injury different from the trampling harm the inadequate barriers risked, operating as a superseding cause.
Record Winds Topple Unsecured Lumber
Harbor Builders left a tall stack of lumber unsecured against an unfinished wall for five days in a high-traffic urban area. An unexpected windstorm with record gusts caused the wall to collapse and the lumber to fall onto the sidewalk, injuring Marie. The extraordinary operation of the windstorm prevented the builders from being liable.
Storm Drives Boat Ashore
A boat owner moored his vessel near shore during calm weather. A sudden tempest drove the boat onto a neighbor's beach. The owner entered the neighbor's land to secure the boat and prevent it from being carried out to sea. The force of nature created the necessity that justified the entry.
Ploof v. Putnam71 A. 188 (Vt. 1908)
Mother Witnesses Child's Injury
A driver negligently struck a child in view of the child's mother standing nearby. The mother suffered emotional distress from witnessing the event. The force of nature did not intervene. The driver's conduct directly created the foreseeable risk of harm to the mother through the impact on her child.
When does an extraordinary force of nature relieve a negligent defendant of liability?+
An extraordinary force of nature relieves liability when its operation is extraordinary and the resulting harm is of a different kind from the risk that made the defendant's conduct negligent.
Supporting sources
Does every intervening force of nature break the chain of causation?+
No. Only an extraordinary force of nature that produces a different kind of harm operates as a superseding cause. Ordinary natural events or those that merely accelerate the same type of harm do not relieve the defendant.
Supporting sources
L.R. 3 H.L. 330 (1868)Torts
…that the escape was owing to the Plaintiff's default; or, perhaps, that the escape was the consequence of vis major, or the act of God; but as nothing of this sort exists here, it is unnecessary to inquire what excuse would be sufficient. The general rule, as above stated, seems on principle just. The person whose grass or…