He returned home after two months and although it was a capital offence to leave one's domain, the domain lord Naomasa NABESHIMA highly regarded Shinpei's views and reduced his punishment to indefinite house arrest via his own direct judgement.
2ヶ月ほどで帰郷し通常脱藩は死罪であったが、新平の見識を高く評価した藩主・鍋島直正の直截裁断により永蟄居（無期謹慎）に罪を軽減されたとされる。