The Rationale and Limitations of the Retroactive Principle in Terrorism Crimes

Abstract

The principle of legality is a fundamental norm in criminal law that prohibits the retroactive application of penal provisions. However, in the context of terrorism, several states, including Indonesia, have implemented retroactive measures as a response to extraordinary crimes that were not yet comprehensively regulated. The issuance of Government Regulation instead of Law (Perppu) No. 1 of 2002 and Perppu No. 2 of 2002 following the 2002 Bali Bombings illustrates the state’s urgent need to address terrorism, which is characterized by its massive, organized, and far-reaching impact on public security. This phenomenon highlights a tension between the legality principle and the retroactive application of terrorism legislation. This study aims to analyze the underlying rationale for the application of retroactivity in terrorism cases in Indonesia and to examine the ideal limits for its implementation. The research employs a normative legal method with historical and conceptual approaches, drawing on primary and secondary legal materials. The findings show that the application of retroactivity is grounded in the characterization of terrorism as an extraordinary crime, the absence of comprehensive legal provisions at the time, and the state’s need to restore public security. Comparative analysis reveals two general models of limiting retroactive legislation: provisions that clearly define temporal boundaries for retroactivity, and those that apply retroactive measures without explicit limitations. Based on these findings, the most appropriate limitation is the establishment of a clear temporal cut-off date that explicitly determines the period from which a regulation is deemed effective.