日本国憲法第38条
No person shall be compelled to testify against himself.
No confession shall be admitted in evidence if made under compulsion, torture or threat, or after prolonged arrest or detention.
No person shall be convicted or punished in cases where the only proof against him is his own confession.
「GHQ草案」、国立国会図書館「日本国憲法の誕生」。