Abolition of Prosecutors' Supplementary Investigation Powers: "Redesign of Corporate Criminal Response Strategies Inevitable"

The initial investigative framework determines the course of the case
Complete legal arguments and evidence must be prepared from the complaint stage

With the amended Criminal Procedure Act, which will take effect on October 2, 2026 and completely abolish prosecutors' supplementary investigation rights, legal experts say that corporate criminal risk management strategies will inevitably need to be redesigned. Professionals from the legal community point out that companies now bear a significant burden of proof from the early stages of an investigation, due to a confluence of factors: a lack of prosecutorial and trial know-how among the police and special judicial police officers, disparities in response capabilities depending on corporate size, and an expansion of unchecked investigative powers leading to broader compulsory investigations.

Democratic Party lawmakers applaud as the partial amendment bill to the Criminal Procedure Act, which mainly abolishes the prosecutor's supplementary investigation authority and was submitted the previous day, passes during the third plenary session of the July extraordinary session of the National Assembly held on the 31st of last month. Photo by Yonhap News Agency

According to the legal community on August 13, with the new law coming into effect, the initial investigative framework established by judicial police and special judicial police officers will likely have a greater impact on the entire direction of each case. This is because prosecutors are now prohibited from directly conducting supplementary investigations and can only intervene by requesting further investigation. The problem is that police and special judicial police officers—often lacking experience in prosecution and trial maintenance—may be unable to anticipate and thoroughly collect evidence on legal issues that could arise as grounds for acquittal during trial. This is especially true for complex corporate cases, such as those involving finance, fair trade, or technology leakage, where investigative gaps are more likely to occur and even when indictments are filed, cases may proceed to trial in an insufficient state.

These changes also introduce new risks for companies acting as victims seeking to file complaints or accusations. Previously, even if police investigations were inadequate, prosecutors could make up for shortcomings through direct supplementary investigations before proceeding to prosecution. With the revised act, however, prosecutors must now decide whether to indict solely based on the investigation records, and—if the police’s supplementary investigation is lacking—they can issue a non-indictment decision without filling in the gaps themselves as was possible in the past. As a result, companies looking to file complaints now face a heavier burden to meticulously assemble the legal theories and evidence to support allegations from the outset. Furthermore, if the police decide not to refer a case for further action, the period for objecting to such a decision is now strictly limited to within three months of receiving the notification. Consequently, it is expected that lawyers with substantial criminal experience will need to essentially play the role of investigator even before a complaint is filed to ensure that enough evidence is collected.

The fact that special judicial police investigations—which were once coordinated under the direction of prosecutors—will now be conducted independently is also seen as a new source of risk. Because prosecutors’ involvement now starts later, only at the stage of search warrant application, there is concern that special judicial police officers—whose experience in prosecution and depth of legal training are limited—could push forward with flawed investigations by making incorrect judgments prior to prosecutorial involvement.

There are also concerns that such structural changes may initially weaken the expertise of investigative authorities. Even after the establishment of a Serious Crimes Investigation Agency specializing in corruption and economic crimes, it may prove difficult to quickly secure sufficient personnel with extensive investigative experience, raising questions about investigative competence. The reduction of the supplementary investigation processing period to one month also places further strain on the process. If supplementary investigations are not completed properly within this tight timeframe, repeated requests and responses between prosecutors and investigative agencies may prolong or frustrate case handling even further.

Jo Kyu-ung, attorney at the Corporate Criminal Response Strategy Center of HwaWoo, commented, "When the point of prosecutorial involvement is delayed until the search warrant application stage, cases will have already undergone considerable preliminary investigation and inquiry." He added, "Even if a company is ultimately exonerated, it will be difficult to avoid substantial real-world damage such as industry rumors and business disruption in the interim." He further noted, "With the diversification of investigative authorities—including the National Police Agency’s Criminal Investigation Headquarters, the new Serious Crimes Investigation Agency, and various special judicial police—companies now face an even greater number of investigative bodies to which they must respond."

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