C Corruption is a serious problem in indonesia, one of which is reflected in the e-ktp procurement case involving paulus tannos as the former director of pt sandipala arthaputra. this case raises legal issues regarding the application of the active nationality principle, as the perpetrator fled abroad and changed his identity and citizenship. this research examines the application of the active nationality principle to the corruption offense committed by paulus tannos, as well as his role as a participant in the e-ktp project. the research employs a normative juridical method with a descriptive-analytical approach. the data used consist of primary data as supporting material and secondary data as the main source. the analysis is conducted qualitatively using deductive reasoning. the results show that the active nationality principle remains applicable because paulus tannos was an indonesian citizen at the time the criminal act was committed, thereby subjecting him to indonesian criminal law. the application of this principle is strengthened by expert opinions emphasizing that effective law enforcement requires the support of extradition mechanisms and the fulfillment of the double criminality principle. furthermore, paulus tannos’s involvement in the e-ktp project consortium indicates his role as a form of criminal participation, specifically as a co-perpetrator (medeplegen) together with other offenders.