Constitution of the Republic of Singapore · 2020 Revised Edition · Part 4 · Fundamental Liberties
11. Protection against retrospective criminal laws and repeated trials
Feedback & supportNo 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.
law
“law” includes written law and any legislation of the United Kingdom or other enactment or instrument whatsoever which is in operation in Singapore and the common law in so far as it is in operation in Singapore and any custom or usage having the force of law in Singapore;
A person who has been convicted or acquitted 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 convicted or acquitted.