Criminal Procedure Act Amendment Removes Prosecution's Investigative Authority... Joint Investigative Units Face Collapse, CIO and Special Prosecutors Also Face Legal Uncertainty

No Criteria Provided for Succession of Existing Cases
Transfer to Serious Crimes Investigation Agency
Makes It Difficult to Maintain Collaboration Networks
"Doubts Remain Whether Joint Units Will Function Properly"

Although the amendment to the Criminal Procedure Act, which abolishes prosecutors' authority to conduct direct investigations and supplementary investigations, has passed the National Assembly, it has been confirmed that a follow-up system for specialized joint investigation units—traditionally operated under the prosecution—has not yet been established. There are concerns that moving these organizations to agencies such as the Serious Crimes Investigation Agency or the police may weaken investigative capabilities, as it will be difficult to maintain the same pool of specialized personnel, investigative experience, and cooperation networks with related agencies.

Supreme Prosecutors' Office, Seocho-gu, Seoul. Photo by Yonhap News

According to the legal community on August 4, the recent amendment to the Criminal Procedure Act, which passed the plenary session on July 31, excludes prosecutors from being the main investigative body and eliminates the legal basis for direct investigations and supplementary investigations in transferred cases.

However, the amendment does not include separate grounds for prosecutors to participate in joint investigation headquarters, divisions, or teams, nor does it set criteria for the succession of existing cases or personnel. Although it may be interpreted that prosecutors without investigative authority can still engage in case consultations or legal reviews, if they become substantively involved in directing the investigation—such as determining the investigative direction, targets of search and seizure, or handling suspects' detention—it could be considered de facto command of the investigation. There are also concerns that the defense may claim violations of due process or illegal evidence collection, exposing significant legal risks if the current system were to be maintained based solely on such interpretations.

Currently, five specialized joint investigation units are operated with the prosecution as the base: the Suwon District Prosecutors’ Office Government Joint Anti-Narcotics Investigation Headquarters, the Seoul Southern District Prosecutors’ Office Financial & Securities Crime Joint Investigation Division, the Seoul Southern District Prosecutors’ Office Virtual Asset Crime Joint Investigation Division, the Seoul Eastern District Prosecutors’ Office Voice Phishing Crime Joint Investigation Division, and the Seoul Northern District Prosecutors’ Office National Finance Crime Joint Investigation Team. The strength of this model lies in the structure where dispatched personnel from the police, Korea Customs Service, and financial authorities share information with prosecutors from the early stages, enabling seamless cooperation from compulsory investigations and warrant applications to indictments.

A deputy chief prosecutor working in a joint investigation division stated, "The core of the joint investigation unit is that the police team's investigative plans are shared in the same space and that prosecutors can immediately review and request warrants, greatly improving both speed and quality of investigations. Without the prosecution, the joint investigation unit loses its meaning."

Even if the organization is transferred to the Serious Crimes Investigation Agency, there is no guarantee that existing prosecutors and investigators will move together. Intelligence networks, overseas cooperation channels, and informant networks that the joint investigation units have built would take time to rebuild if members disperse. A senior prosecutor specializing in narcotics investigations pointed out, "With the current system, it will be difficult for the joint investigation units to function properly after October. Once narcotics crimes start to rise, they rarely decrease, so the spread of investigative gaps is a serious concern."

Similar legal uncertainties are observed with the Corruption Investigation Office for High-ranking Officials (CIO) and the special prosecutor system. The amendment ties the investigative authority of CIO prosecutors to a transitional provision in the supplementary rules, rather than the main text of the Criminal Procedure Act. As a result, controversy is expected over the appropriateness of exercising key powers of a permanent investigative body based on a supplementary provision.

Although special prosecutors, their assistants, and dispatched prosecutors will, for the time being, be able to continue investigations in accordance with the respective special prosecutor laws and transitional measures, there remains the possibility that the defense will challenge the legitimacy of their investigative and evidence-gathering procedures due to the removal of prosecutors’ investigative authority in the main statute, raising questions about legal consistency.

Within the legal community, there are calls to clarify, by October 2 when the new system is slated to begin, the scope of prosecutors’ participation in joint investigation organizations as well as criteria for the succession of professional personnel and intelligence networks. It is also suggested that the legal basis and applicable scope of the CIO and special prosecutors' investigative authority require clearer statutory definitions.

This content was produced with the assistance of AI translation services.