Also known as: superseding cause · intervening cause · superseding causes · intervening causes
Written by attorneys · grounded in primary & secondary sources — see below
A doctrine under which an intervening act or force that is not a normal consequence of the actor's negligence breaks the chain of proximate causation and relieves the original actor of liability for the resulting harm.
Select any source to read its text and confirm it supports the definition.
Sabrina Shah left her front door unlocked after forgetting to secure it following a delivery. A burglar entered hours later and assaulted Scott Summers who was visiting. The burglar's deliberate criminal act relieved Sabrina of liability for Scott's injuries even though her unlocked door created the opportunity.
Sophia Singh left a ladder leaning against a building without securing it. Sasha Stone climbed the ladder to rescue a child who had become stuck on a ledge after the ladder shifted. Sasha's rescue effort was a normal response and did not relieve Sophia of liability for Sasha's resulting fall.
Simone Sanders positioned a large crane load near a public viewing area at a wind farm. A sudden gust swung the load and injured Steven Silva. The gust's operation appeared extraordinary rather than normal given the circumstances and therefore constituted a superseding cause relieving Simone of liability.
Starlight Media stored unstable scaffolding near a busy sidewalk without barriers. A pedestrian's ordinary use of the sidewalk caused the scaffolding to topple onto a passerby. Because the media company had increased the foreseeable risk of harm through the intervention of another force the intervention was not superseding.
Synergy Systems left an unsecured gate open near a playground. A child panicked and ran into traffic upon seeing a loose dog approach. The child's fear-driven act was a normal response to the situation created by the company's negligence and did not relieve the company of liability for the resulting injuries.
Summit Bank left a heavy vault door propped open in a customer area. A teller attempted to close the door to prevent it from falling on customers. The teller's normal effort to avert the threatened harm was not a superseding cause of injuries sustained when the door shifted.
A superseding cause is an intervening force that by its intervention prevents the original actor from being liable because it is not a normal consequence of the actor's negligence. The Restatement lists factors such as whether the harm differs in kind from that which would otherwise have resulted and whether the intervention appears extraordinary rather than normal.
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…knocks down with his car a pedestrian and a third person then ran over the prostrate person. That involves the question of intervening cause which we do not have here. Moreover it is out of harmony with the current rule on that subject and was properly questioned in Hill v. Peres , 136 Cal.App. 132 [28 P.2d 946] (hearing in…
…the buyer's knowledge of a defect breaks the chain of proximate causation because
…of its approach limit a manufacturer’s liability if the subsequent alteration or modification was the sole proximate cause
…first place, we are committed to the rule in negligence cases that where in the natural and continual sequence, unbroken by any intervening cause
…city’s failure to maintain its sewer line were directly and proximately cause
No. A natural force such as wind qualifies as superseding only when its operation or consequences appear extraordinary rather than normal in view of the circumstances existing at the time. When the actor has created a situation in which the force is foreseeable the intervention does not relieve liability.
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An intervening criminal act is superseding when it prevents the actor from being liable for harm that the antecedent negligence was a substantial factor in bringing about. The act must not be a normal consequence of the situation the actor created.
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Normal efforts by the victim or a third person to avert harm threatened by the actor's negligence are not a superseding cause. The original actor remains liable for harm resulting from those efforts.
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No. The fact that an intervening act of a third person is negligent in itself does not make it a superseding cause if the actor's negligent conduct remains a substantial factor in bringing about the harm.
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