This is believed to have occurred because his oldest brother Koretada had a plan to hold power over the Imperial Court in order to establish his own government and Kaneie was involved in this plan, and this has been believed to prove that Kaneie was involved in the Anna no hen (the Anna Incident).
これは、長兄伊尹が自己の政権基盤確立のための宮中掌握政策の一翼を兼家が担っていたからだと考えられ、安和の変に兼家が関与していたとされる説の根拠とされている。