C Criminal law enforcement must ensure legal certainty, the protection of human rights, and adherence to the principle of due process of law. one form of oversight is implemented through the institution of pretrial proceedings (praperadilan). the determination of a suspect has become one of the objects of pretrial review whose legality may be examined since the issuance of constitutional court decision no. 21/puu-xii/2014. pursuant to this decision, the designation of a suspect must be based on at least two items of evidence and be accompanied by the examination of the prospective suspect.the main issue examined in this research is how the determination of a suspect in pretrial decision no. 1/pid.pra/2023/pn cjr should be assessed in light of the indonesian code of criminal procedure (kuhap), constitutional court decision no. 21/puu-xii/2014, and other relevant statutory regulations, as well as whether the legal considerations and ruling in pretrial decision no. 1/pid.pra/2023/pn cjr are consistent with the applicable indonesian criminal procedural law, particularly constitutional court decision no. 21/puu-xii/2014.this study employs a normative legal research method with a descriptive-analytical approach. the data are analyzed qualitatively, and conclusions are drawn using a deductive method.the findings indicate that the pretrial judge declared the designation of the applicant as a suspect to be lawful because it was based on evidence deemed to satisfy the requirements of indonesian criminal procedural law. nevertheless, issues remain concerning the examination of the prospective suspect in relation to the principle of due process of law, as emphasized in constitutional court decision no. 21/puu-xii/2014. therefore, the implementation of constitutional court decision no. 21/puu-xii/2014 in the a quo case is considered not to have been carried out comprehensively, particularly with respect to the judicial review of the procedural aspects of suspect designation.