Proximate Cause
Proximate cause is the dominant, effective cause of an insurance loss — the event that set the chain of events in motion leading to the claim. Insurers use proximate cause to determine whether a loss falls within policy coverage or an exclusion.
Definition
In insurance, proximate cause is the active, efficient cause that produces a loss — the event that is most directly responsible for the outcome, even when other events contributed to the chain. It is not necessarily the first event in a sequence, nor the last — it is the dominant or effective cause.
The classic insurance law formulation comes from the UK House of Lords case Leyland Shipping Co v Norwich Union Fire Insurance Society (1918): "The causa proxima non remota spectatur" — look to the proximate, not the remote, cause. This principle means insurers do not consider every event in a causal chain — they ask which cause was most directly operative in producing the loss.
Proximate cause in practice
Fire following earthquake
Earthquake (excluded) → gas pipe rupture → fire → property damage. If earthquake is excluded, is the loss excluded? The proximate cause is the earthquake; fire is the consequence. Most policies treat this as an excluded loss.
Storm causes flooding
Storm (covered) → water enters property → water damage. Even if the policy excludes "flood," if the proximate cause is storm rather than an independent flood event, the claim may succeed under the storm peril.
Pre-existing condition and accident
Fall (accident) → injury worsened by pre-existing bone condition (excluded). If the accident is the proximate cause and the pre-existing condition merely made the injury worse, the accidental loss is often covered, though the extent of cover may be disputed.
Proximate cause FAQ
Frequently asked questions
- When multiple events contribute to a loss, insurers apply the proximate cause doctrine to identify the dominant cause. If the proximate cause is a covered peril, the loss is typically covered even if a contributing cause is not. If the proximate cause is an excluded peril, the claim is typically declined even if contributing causes were covered. Courts have developed tests to identify the proximate cause — "efficient proximate cause" and "dominant cause" are the most commonly applied formulations.
- A common proximate cause dispute arises when a storm causes water to enter a property. The question is whether the proximate cause is "storm" (covered) or "flood" (sometimes excluded). Courts have generally held that if the storm was the dominant cause and flooding was a consequence of the storm rather than a pre-existing or independent flood event, the claim should be covered under the storm peril. The specific policy wording and local case law determine the outcome. See our flood insurance guide for more on peril definitions.
- The insurance concept of proximate cause is related to but not identical to legal causation in tort. In law, "but for" causation and remoteness of damage are the key tests. In insurance, the question is more specifically about which peril is the dominant cause — because the policy only covers named or all-risks perils, and specific exclusions apply. Insurance case law has developed its own proximate cause doctrine, drawing on but not identical to general negligence principles.