We previously reported the Washington Supreme Court’s decision in Xia, et al. v. ProBuilders Specialty Insurance Company, et al., 188 Wn.2d 171, 393 P.3d 748 (2017), in which the Court applied the efficient proximate cause rule to a third-party liability policy to find a duty to defend.

To recap, Washington law requires insurers to assess and investigate coverage under first-party insurance policies by applying the efficient proximate cause analysis. Until Xia, the efficient proximate cause rule has only been applied to first party insurance policies in Washington. But the Washington Supreme Court’s decision in Xia changed that by holding that an insurer must consider the efficient proximate cause rule in determining its duty to defend under a CGL policy.

The issue in Xia was whether the pollution exclusion applied to relieve ProBuilders of its duty to defend a claim against the insured alleging that carbon monoxide was released into the claimant’s house through a defectively installed vent. ProBuilders denied coverage to the insured contractor, in part, under the pollution exclusion. The Washington Supreme Court held that while ProBuilders did not err in determining that the plain language of its pollution exclusion applied to the release of carbon monoxide into Xia’s home, “under the ‘eight corners rule’ of reviewing the complaint and the insurance policy, ProBuilders should have noted that a potential issue of efficient proximate cause existed,” as Xia alleged negligence in her original complaint, i.e. failure to properly install venting for the hot water heater and failure to properly discover the disconnected venting.

Ultimately, the Court concluded that the efficient proximate cause of the claimant’s loss was a covered peril – the negligent installation of a hot water heater. Even though ProBuilders correctly applied the language of its pollution exclusion to the release of carbon monoxide into the house, the Court ruled that ProBuilders breached its duty to defend as it failed to consider an alleged covered occurrence that was the efficient proximate cause of the loss. The Court granted judgment as a matter of law to the claimant with regard to her breach of contract and bad faith claims.

Soon after the Washington Supreme Court’s decision, ProBuilders filed a motion asking the Court to reconsider its decision. However, on August 17, 2017, the Washington Supreme Court denied the motion, leaving in place the holding that insurers must take the efficient proximate cause rule when analyzing coverage under third-party policies.

As discussed in our earlier post, the efficient proximate cause rule applies “when two or more perils combine in sequence to cause a loss and a covered peril is the predominant or efficient cause of the loss.” Vision One, LLC v. Philadelphia Indemnity Insurance Co., 174 Wn.2d 501, 276 P.3d 300 (2012). “If the initial event, the ‘efficient proximate cause,’ is a covered peril, then there is coverage under the policy regardless of whether subsequent events within the chain, which may be causes-in-fact of the loss, are excluded by the policy.” Key Tronic Corp., Inc. v. Aetna (CIGNA) Fire Underwriters Insurance Co., 124 Wn.2d 618, 881 P.2d 210 (1994).

Insurers must be extremely cautious when assessing the duty to defend and an exclusion that could potentially preclude coverage. Under Xia, liability insurers must examine the underlying complaint very carefully to determine whether there could potentially be multiple causes of a loss, and if so, which cause is the initiating cause. If the initiating cause is potentially a covered event, then there may be coverage and the insurer must provide a defense under reservation of rights in order to minimize bad faith exposure.