The content of his confession was that after the coup of August 18, the Choshu-jin (Choshu citizen,) etc. forced out of Kyo would set fire to the Imperial Palace on an certain very windy day in late June, thus confining Crown Prince Asahiko KUNINOMIYA, a Sabaku-ha (a group of feudal government supporters) court noble; and would then kill Katamori MATSUDAIRA and other Sabaku-ha Daimyo (feudal lords who supported the feudal government) and take the Emperor to Choshu.
その内容は、八月十八日の政変後、京を追われた長州人らが六月下旬の強風の日を選んで御所に火を放ち、佐幕派公家の久邇宮朝彦親王を幽閉し京都守護職の松平容保以下佐幕派大名を殺害し、天皇を長州へ連れ去ろうとするものだった。