(1) No person shall be held in slavery.

6. (1) No person shall be held in slavery. (2) All forms of forced labour are prohibited, but Parliament may by law provide for compulsory service for national purposes. (3) Work or service required from any person as a consequence of a conviction or a finding of guilt in a court of law shall not be taken to be forced labour within the meaning of this Article, provided that such work or service is carried out under the supervision and control of a public authority. (4) Where by any written law the whole or any part of the functions of any public authority is to be carried on by another public authority, for the purpose of enabling those functions to be performed the employees of the first-mentioned public authority shall be bound to serve the second-mentioned public authority, [Article 6] Federal Constitution 23 and their service with the second-mentioned public authority shall not be taken to be forced labour within the meaning of this Article, and no such employee shall be entitled to demand any right from either the first-mentioned or the second-mentioned public authority by reason of the transfer of his employment. Protection against retrospective criminal laws and repeated trials