The purpose of this study is to draw out the social welfare meanings in the "Dementia Railroad Accident Trial" by analyzing articles and documents about the trial, and to examine the descriptions at issue in this trial. This study examines the organization of the defendant support network, the debate over the "socialization of risk," the relationship between the judiciary and the enforcement of the policy, and the discomfort of describing an accident caused by a dementia patient as an "assailant.” The organization of the defendant support network was deeply related to the philosophy of elderly welfare and mental health welfare administration. In addition, after the ruling from the Supreme Court, there was much discussion about the "socialization of risk.” Finally, I pointed out the inappropriateness of the descriptions of "assailant" and "wandering," which are strongly related to this court decision.