Section I. Criminal Law
Article 4. The Action of the Criminal Code in Time
The criminality and punishability of an act shall be defined by the law which was in effect during the time of the commission of that crime. The time of the commission of a socially dangerous act (failure to act), irrespective of the time of the emergence of consequences, shall be recognised as the time of the commission of a given crime.
Non-retroactivity
Nullum crimen sine lege
Nulla poena sine lege
EDIT.