In areas such as pharmaceuticals, where licensing or restriction of use is based on statistical scientific evaluation of efficacy and safety, value conflicts between efficacy and safety always occur. In addition, serious value conflicts between the producers who develop pharmaceutical products and consumers who may have suffered their side effects or other safety-related damages have often resulted in litigation. Using two lawsuits concerning pharmaceutical products in which the author testified as examples, I would like to examine how this type of value conflict is statistically expressed and what criteria of ethics are involved in value conflicts.