日本国憲法第21条
Freedom of association, movement and choice of abode are guaranteed to every person to the extent they do not conflict with the general welfare.
All persons shall be free to emigrate and to change their nationality.
Freedom of assembly, speech and press and all other forms of expression are guaranteed. No censorship shall be maintained, nor shall the secrecy of any means of communication be violated.
東京法律研究会 p.8
日本臣民ハ法律ニ定メタル場合ヲ除ク外信書ノ祕密ヲ侵󠄁サルヽコトナシ