In this court of appeal judgment, the court upheld the findings of the lower court discussed here.

The question was whether loss or damage caused in 2021 by the controlled detonation of a previously undiscovered World War II bomb was “occasioned by war” and excluded by the applicable insurance policy.

Damage had been suffered to the insured premises (which did not exist at the time that the bomb was dropped) when a controlled detonation of the discovered bomb took place in 2021.

Both the lower and appeal court accepted that the war exclusions were a part of the definition of the scope of cover.

On appeal the question was whether the dropping of the bomb was either the proximate cause of the damage or a proximate concurrent cause, for the exclusion clause to take effect.  It was agreed that “occasioned by” gave rise to the proximate cause test.  It did not matter that the clause did not refer to “directly or indirectly occasioned by”, and the parties agreed that the proximate cause test had to be applied.

It was agreed that the dropping of the bomb was an act of war. And it was agreed that the war exclusion clause would apply unless the insured could show that the dropping of the bomb was not the proximate cause, or a concurrent proximate cause of approximately equal efficiency, of the loss and damage.

It was also accepted that the mere fact that the detonation of the bomb occurred after the end of the war in which it was dropped did not automatically rule out the operation of the war exclusion clause.

The appeal court accepted that the lower court’s analysis that, on the application of the relevant law to the agreed facts, the loss and damage in 2021 resulted from two concurrent causes of approximately equal efficiency.  One was the dropping of the bomb in 1942. The other its controlled detonation almost 80 years later.  It was the combination of those two causes which made the loss inevitable.  Neither would have caused the loss without the other. They were of approximately equal efficiency. 

Because one of those concurrent causes was expressly excluded from cover under the policy, the exclusion prevailed and there was no cover.

The judgment contains a useful review of English law general principles of proximate cause and concurrent causes.