As a result of recent studies on Heiji War, it has become a prevailing view that Kiyomori was in a neutral position from any party including the Cloistered Emperor Goshirakawa, Emperor Nijo, Shinzei and FUJIWARA no Nobuyori because Kiyomori had a matrimonial relation with Shinzei and was united through marital relations with the son of Nobuyori.
また、近年の平治の乱に対する研究では、清盛は信西と姻戚であると同時に信頼の息子とも婚姻関係を結んでおり、後白河法皇や二条天皇をとりまく勢力や信西、藤原信頼などどの勢力から見ても中立な立場であるという見方が強まりつつある。