Article 7 of the European Convention for the Protection of Human Rights and Fundamental Freedoms and Its Eight Protocols also regulates matters relating to the prohibition of retroactivity, stating No one shall be held guilty of any criminal offence on account of any act or omission which did not constitute a criminal offence under national or international law at the time when it was committed.

Article 15 International Covenant on Civil and Political Rights also explains that:

No one shall be held guilty of any criminal offence on account of any act or omission which did not constitute a criminal offence, under national or international law, at the time when it was committed. Nor shall a heavier penalty be imposed than the one that was applicable at the time when the criminal offence was committed. If, subsequent to the commission of the offence, provision is made by law for the imposition of the lighter penalty, the offender shall benefit thereby.

Article 11 paragraph (2) United Nations Universal Declaration of Human Rights also regulates the prohibition of retroactivity, where No one shall be held guilty of any penal offence on account of any act or omission which did not constitute a penal offence, under national or international law, at the time when it was committed. Nor shall a heavier penalty be imposed than the one that was applicable at the time the penal offence was committed. In fact, Article 9 (Freedom from Ex Post Facto Laws) American Convention on Human Rights also regulates the same thing, namely:

No one shall be convicted of any act or omission that did not constitute a criminal offence, under the applicable law, at the time it was committed. A heavier penalty shall not be imposed than the one that was applicable at the time the criminal offence was committed. If subsequent to the commission of the offence the law provides for the imposition of a lighter punishment, the guilty person shall benefit there from.

If we trace its history further, the enactment of the principle of legality as opposed to the retroactive principle is actually an influence from the Bill of Rights of Virginia in 1776 in the United States. In this Bill of Rights it is only determined that no one may be prosecuted or arrested other than

by and by events contained in the law . Thus, this principle is seen as providing protection against arbitrary demands and arrests by the authorities against someone.According to Moeljanto, the spirit of the Bill of Rights was brought by General Lafayette to France through Article 8 of the Declaration Des Droits De L'Homme Et Du Citoyen in 1789 which reads: "No one can be punished except by the force of a pre-existing law" and included in Article 4 of the French Penal Code under the Napoleonic Government and subsequently adopted by the Netherlands through the Wetboek van Straftrecht and then entered by concordance through Article 1 paragraph 1 of the Indonesian Criminal Code.

This writing is an excerpt from the book:

Zaka Firma Aditya, Retroactive principle of the Constitutional Court's decision in theory and practice, (Jakarta: RajaGrafindo, 2020).

If Literacy Friends want to read it in full, you can buy the book through the following link:

Book Purchase Link

References:

Bryan A. Garner, Black’s Law Dictionary,Ninth Edition,