The insuring agreement often incorporates the "known loss doctrine," generally with words to the effect that the policy covers "bodily injury or property damage that was not, prior to the policy period, known to have occurred by any insured."
The known loss doctrine is one of the most basic concepts of insurance coverage. Insurance is supposed to be a gamble: You pay $1.00 in premiums now as a gamble against the risk that without the insurance you would have to pay $10.00 in loss (or attorney's fees) in six months. You can play the odds by negotiating premiums against limits. If the premiums become too high vis a vis the chances of the insured event occurring (many people--but not me--say this is the case with disability insurance) or the maximum payout is too low (generally, dental insurance), you choose not to purchase the insurance.
The whole system falls apart if you purchase insurance for a loss you already know has occurred. In law school parlance, the insurance is no longer against a "fortuitous" event.
Litigation around the known loss doctrine predictably concerns what it means to be "known": who knew, what they knew, and when they knew it. The issue frequently comes up in environmental contamination litigation: An insured may argue that although there was some evidence of contamination at the time the policy began, the insured did not know the extent of the contamination. The Supreme Judicial Court of Massachusetts has stated in this context that the only requirement for the loss to be exempt from coverage is that "the insured has evidence of a probable loss when it purchases the policy." SCA Services, Inc. v. Transportation Ins. Co., 419 Mass. 528, 533 (1995).
Another common context for the known loss doctrine is construction defect litigation. Arguments frequently arise about punch lists demonstrating problems such as lack of caulking or other insufficiencies in the building envelope. Insurers argue that those punch lists show that the insured contractor was aware of probable water infiltration into the building, while the insureds argue that the punch list only demonstrated that the contractor had work to do before the job was finished.
In a future post I will discuss how the known loss doctrine applies where the insured knew of the occurrence but did not know that the occurrence could lead to liability.