[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 7. (1) No person shall be punished for an act or omission which was not punishable by law when it was done or made, and no person shall suffer greater punishment for an offence than was prescribed by law at the time it was committed. (2) A person who has been acquitted or convicted of an offence shall not be tried again for the same offence except where the conviction or acquittal has been quashed and a retrial ordered by a court superior to that by which he was acquitted or convicted. Equality 8. (1) All persons are equal before the law and entitled to the equal protection of the law. (2) Except as expressly authorized by this Constitution, there shall be no discrimination against citizens on the ground only of religion, race, descent, place of birth or gender in any law or in the appointment to any office or employment under a public authority or in the administration of any law relating to the acquisition, holding or disposition of property or the establishing or carrying on of any trade, business, profession, vocation or employment. (3) There shall be no discrimination in favour of any person on the ground that he is a subject of the Ruler of any State. (4) No public authority shall discriminate against any person on the ground that he is resident or carrying on business in any part of the Federation outside the jurisdiction of the authority. (5) This Article does not invalidate or prohibit— (a) any provision regulating personal law; (b) any provision or practice restricting office or employment