Clearly, violation of this WAC cannot be used to support a claim against a third party insurer under IFCA: http://apps.leg.wa.gov/RCW/default.aspx?cite=48.30.015 That is one of the major reasons I recommend my clients use their first party coverage (if available) to settle their property damage claims. I am assuming you don't have first party coverage. It looks like the third party insurer has decided there is comparative fault, and in my opinion WAC 284-30-391 probably won't be effective as a tool to get the insurer to give up their right to defend their insured's driving (liability). I strongly recommend you consult a competent attorney in your jurisdiction to discuss these issues as soon as possible.
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