Inappropriate sentencing causes a request for appeals. In this case, what criterion might be employed? Is there any conflict between the previous verdict and the laws? These are the concerns. Since the death penalty is the ultimate punishment, the ruling usually details the grounds which reveal the procedure of reviewing sentences in the court of appeals. Therefore, this article investigates two judgements of the Supreme Court of Japan on 3rd February 2015 acknowledging the reversed death sentencing on appeal. The rationales articulated by Japanese courts might shed light on the judicial path for Taiwanese theory and practice.