It is said that he attempted to disembowel himself at the time of arrest and died of the wound the next day in jail ("Zoku kojidan"(Ancient Matters)).
なお、逮捕の際、保輔は自らの腹部を刀で傷つけて自害を図り、翌日その傷がもとで獄中で没したという（『続古事談』）。