This measure is thought to be taken due to the belief that if WATANABE, who was the chief officer of the Imperial mourning, was arrested during the time of the Imperial mourning which lasts for about three months, the Imperial Household Ministry's dignity would be lost.
大喪最高責任者となるはずの渡辺が大喪の終るまでの約3ヶ月の間にもし逮捕されると、宮内省の威信が地に落ちると考えられたためと思われる。