Some say Masako HOJO, in fear of decline of her own influence in the Kamakura bakufu due to having no blood relationship with the Shogun family and the weak connection with the head family of HOJO, designed this incident, which has the same content with the Incident of Maki clan, in order to forcibly ruin the Iga clan, who were to hold strong power as Yoshitoki's widow.
この事件は、すでに将軍家と血縁もなく、北条本家との関係も希薄となって影響力の低下を恐れた政子が、牧氏事件と同じ構図を創り上げて義時後家として強い立場を持つ事になる伊賀氏を強引に潰そうとして仕掛けたものとする見方もある。