CHAPTER IV
HUMAN RIGHTS
42. Arrest, detention and fair trial
(2) Every person arrested for, or accused of, the alleged commission of an offence shall, in addition to the rights which he or she has as a detained person, have the right —
(f) as an accused person, to a fair trial, which shall include the right —
(vi) not to be convicted of an offence in respect of any act or omission which was
not an offence at the time when the act was committed or omitted to be done, and not to be sentenced to a more severe punishment than that which was applicable when the offence was committed ;
EDIT.