In a negligence case from Portland, Oregon, where the stopped car of a plaintiff with an “eggshell” neck and back was rear-ended, Roberta Haas requested a “substantial factor” instruction on causation because of concerns that “a but-for instruction can wrongly be understood to undermine what is commonly referred to as the ‘eggshell skull’ rule.” Although the Oregon Supreme Court affirmed a decision that rejected the request, it closed by discussing alternative instructions that may help jurors “understand the relationship …