對配偶的不忠行為相對人的精神損害賠償請求—對最高裁判所2019年2月19日民集73卷2號187頁的評釋

Compensation Claim for Mental Damages of the Spouse's Infidelity Relative — Commentary on the Supreme Court’s Case of February 19, 2013 Vol. 73, No. 2, Page 187 of Collection of Civil Judgments

自1978年3月30日最高裁判所做出判決後，對配偶的不忠行為相對人的精神損害賠償請求的訴訟數量急劇增加。這種訴訟也形成了和交通事故案件類似的、所謂的賠償金額的“市場行情”，而在學界也存在否定這種請求權的有影響力學說。2019年2月19日最高裁判所的判決沒有否認以不忠行為為由的侵權責任，但是判決認為當事人不負有因不忠行為導致夫妻離婚為理由的侵權責任。這個判決認為夫妻關係是根據夫妻雙方的意思、由夫妻雙方進行決定。這個判決給配偶的不忠行為相對人責任問題以再度思考的機會，同時對離婚精神損害賠償金等離婚給付問題也造成了影響。

In Japan, the practice of one spouse exercising the right to claim compensation for mental damage against the other person in the spouse’s act of infidelity was established by case law in the 1920s. In recent years, some new developments have been made, such as stipulating the statute of limitations for the extinction of this right of claim; defining infidelity as a joint infringement, the liability for damages owed by both parties to the infidelity as the unreal joint obligation; the order of occurrence of marriage breaches and infidelity. The 2019 case of the Supreme Court further draws a line between the two kinds of right of claim， "compensation for mental damage based on infidelity" and "compensation for mental damage based on divorce". No matter how the case law develops and changes, the principle that should be grasped is: the legal interests suffered by the betrayed spouse are opposite to the legal interests of the spouse who did the infidelity act such as freedom of love and divorce, and the adjustment of these legal interests should be handled by the family law. Only in special cases can it be regulated by the law of tort liability.