Concurrent Causation and Efficient Proximate Cause: Why the Same Damage Can Be Both Covered and Excluded
When a covered peril and an excluded peril combine to cause one loss, the answer depends on which state's causation rule applies — and how well the damage is segregated.
Property losses rarely have one clean cause. A hurricane brings wind and flood. A pipe burst brings water damage on top of pre-existing wear. The legal question is what happens when a covered peril and an excluded peril combine to cause a single loss.
Texas follows the doctrine of concurrent causation. Under JAW The Pointe, L.L.C. v. Lexington Insurance Co., 460 S.W.3d 597 (Tex. 2015), the insured bears the burden of segregating covered damage from excluded damage. If the record cannot distinguish wind damage from flood damage, the insured loses the disputed portion.
Many other states — including Oklahoma in most contexts — apply the Efficient Proximate Cause (EPC) rule. Under EPC, if the dominant, initiating cause of the loss is a covered peril, the entire loss is covered even if excluded perils contributed downstream. Some states have modified EPC by statute or endorsement (California, Washington, and others), and 'anti-concurrent causation' clauses in modern HO-3 and commercial policies attempt to contract around EPC entirely.
The practical consequence: on the same set of facts, the same claim can pay in full in an EPC state and pay a fraction in a concurrent-causation state — depending entirely on how the damage is documented and segregated. That is why a line-item scope, dated photographs, and an engineer's causation opinion are worth more than any argument at the settlement table.
Citations: JAW The Pointe v. Lexington, 460 S.W.3d 597 (Tex. 2015); Garvey v. State Farm Fire & Cas. Co., 770 P.2d 704 (Cal. 1989) (EPC).