Legal community warns that abolishing prosecutors' supplementary investigation authority would collapse the criminal justice system

The Supreme Prosecutors' Office of the Republic of Korea (SPO) said on the 19th that it held a meeting with the heads of major petrochemical companies, chaired by Justice Minister Ahn Duk-geun, to explore ways to strengthen the industry's competitiveness amid a global supply glut. The meeting comes 100 days before the SPO is dismantled, the Public Prosecution Office is created to handle only prosecution functions, and the Serious Crime Investigation Agency is established to investigate major crimes. However, legal experts are warning that separating investigation and prosecution could throw the criminal justice system into confusion. They argue that prosecutors' controversial supplementary investigation authority should be retained, along with tools such as evidence-collection powers that would allow prosecutors to effectively intervene in cases transferred by police.
At the Criminal Justice Forum held on the 25th at L Tower in Seoul's Seocho-gu, the Supreme Prosecutors' Office Legal Training Institute and the Korean Institute of Criminology and Justice (KICJ) offered similar advice from legal practitioners.
In his presentation, Park Kyung-kyu, Director-General of the Criminal Legislation Research Division at KICJ, argued that investigative authority and prosecutorial authority cannot be fully separated in functional terms, and that police-prosecutor cooperation must be strengthened during the investigation process. He pointed out that it would not be easy for prosecutors to judge the legality of a police investigation or whether to indict based only on written records. Referring to the Crown Prosecution Service Charging Guidelines in the United Kingdom, which are seen as the origin of prosecution reform centered on separating investigative and prosecutorial powers, he said that the Criminal Procedure Act of the Republic of Korea regulates cooperation only "in a much narrower scope and in a weaker form." In other words, he said the current system is overly focused on post-investigation oversight after police close a case for the first time, which could lead to poor investigations and delays.
In his second presentation, Jang Jun-ho, Chief Prosecutor of the Gangneung Branch of the Chuncheon District Prosecutors' Office, directly raised the issue of supplementing evidence in transferred cases. He said that if prosecutors lose their direct investigative authority, they would "have no choice but to assess the level of proof in a case by looking only at the transferred records," and predicted that "differences in evidentiary standards between police and prosecutors will not be resolved by requests for supplementary investigation alone, which will lead to more non-indictment decisions made without sufficient investigation." He also said that if prosecutors no longer review transferred records, investigative gaps will inevitably emerge in cases involving police misconduct and offenses that undermine judicial order, such as false accusation and perjury. He added that after the 2022 revision of the Regulations on the Scope of Crimes for Which Prosecutors May Initiate Investigations partially restored prosecutors' ability to investigate, perjury cases increased by 59.2 percent and false accusation cases by 68.8 percent.
Jang also stressed that the core of the system lies in effectiveness, not in the name of the authority. "What really matters is not whether the power called 'supplementary investigation authority' is retained, but whether there are effective and clear rules on evidence-collection powers," he said, adding that any future revision of the Criminal Procedure Act of the Republic of Korea must include evidence-gathering tools that allow prosecutors to uncover the truth and quickly free unjustly accused suspects from the process.
Panelists agreed with the thrust of the two presentations and warned that if prosecutors' supplementary investigation authority is abolished, the criminal procedure system will collapse.
Lee Chang-hyun, a professor at Hankuk University of Foreign Studies Law School, said that because the Constitution grants only prosecutors the right to request warrants, it recognizes prosecutors' ability to exercise investigative authority directly or through investigative command. "We cannot deny prosecutors supplementary investigation authority," he said. He added that the Public Prosecution Office Act's reference to "deciding whether to file charges and matters necessary to maintain them" is effectively supplementary investigation, and stressed that any revision of the Criminal Procedure Act of the Republic of Korea must include provisions enabling such investigations.
Cha Ho-dong, a partner attorney at Lee & Ko, approached the issue from the perspective that investigations belong to the judicial sphere. He said that "the entity that imposes punishment when wrongdoing occurs must be the 'judiciary' under our constitutional system," and added that "the determination of guilt and whether punishment should be imposed must fall within the judicial domain." He argued that giving a first-stage investigative agency with strong investigative powers de facto prosecutorial authority, through non-transfer decisions, while removing the prosecutor's active and preemptive oversight as a quasi-judicial body amounts to "strong investigative power plus weak oversight" and violates the rule of law.
kyu0705@fnnews.com Kim Dong-gyu Reporter