Customary international law

Estonia

Estonia - Penal Code 2001 (2020) EN

Part 1 GENERAL PART
Chapter 1 GENERAL PROVISIONS

ยง 5. Temporal applicability of penal law
(4) Offences against humanity and war crimes shall be punishable regardless of the time of commission of the offence.

Rome Statute

Article 10

Nothing in this Part shall be interpreted as limiting or prejudicing in any way existing or developing rules of international law for purposes other than this Statute.