Police Investigation Scope Has Actually Shrunk

A document summarizing critical assessments and the background behind claims that after the adjustment of investigative powers between the prosecution and police, the police's substantive investigativ

Police Investigation Scope Has Actually Shrunk

Overview

The phrase “police investigation scope has actually shrunk” refers to a critical diagnosis that after the 2021 adjustment of investigative powers between the prosecution and police took effect, the police’s substantive investigative scope, far from expanding, actually contracted. Under the institutional design, the police became the primary investigator of all crimes, but because the prosecutor’s right to request supplementary investigation and reinvestigation and the prosecutor’s direct investigative authority over certain crimes were maintained, critics argue that final control over actual case handling still remains with the prosecution. This document summarizes the background, issues, statistics, and latest trends of this debate.

Main Content

Background: Adjustment of Investigative Powers Between the Prosecution and Police

In January 2020, the National Assembly passed amendments to the Criminal Procedure Act and the Prosecutors’ Office Act, and the so-called “adjustment of investigative powers between the prosecution and police” legislation took effect on January 1, 2021. The core of the amendments was to ① grant the police primary authority to conclude investigations (the power to decide not to refer a case), ② abolish the prosecutor’s authority to direct investigations, ③ legislate procedures for case transfer and reassignment, and ④ limit the prosecutor’s control over the handling of complaints and accusations. The legislative purpose was to check power through the dispersion of investigative authority and to protect the people’s human rights.

Core Structure of the System

Even under the amended law, the police’s authority is not complete. Prosecutors may make requests for supplementary investigation regarding cases referred to them, and may request reinvestigation of cases in which the police decided not to refer. In addition, prosecutors may directly initiate investigations into the so-called “six major crimes,” including corruption, economic crimes, crimes by public officials, election crimes, defense procurement, and large-scale disasters. These provisions act as mechanisms limiting the scope within which the police can effectively close cases.

Why Is There an Assessment That It “Rather Shrank”?

The critical argument runs as follows. First, although the police took charge of primary investigation and decisions not to refer, if the prosecutor’s requests for supplementary investigation are repeated, the case is in effect reorganized according to the prosecution’s will. Second, because areas of direct prosecution investigation, such as the six major crimes, explicitly remain, the scope of high-risk and high-difficulty cases the police can handle is instead limited. Third, although the abolition of investigative direction authority increased police autonomy, the perception spread that responsibility and burden for closing cases were shifted onto the police. Fourth, due to limitations in organizational size, budget, and specialized personnel, substantive investigative capacity was not expanded.

Statistics and Practical Issues

After implementation, the proportion of cases the police closed on their own (non-referral) increased, but the number of the prosecution’s requests for supplementary investigation and reinvestigation also remained significant. In practice, conflicts between the prosecution and police over the “scope of requests for supplementary investigation” were repeated, and in 2022 follow-up legislation to clarify the scope and procedures of supplementary investigation authority was pursued, drawing opposition from the police. In this process, a self-deprecating assessment spread within the police that “authority increased, but the substantive investigative scope shrank.”

Arguments For and Against

Supporters believe that the dispersion of investigative authority and checks contribute to human rights protection and prevention of abuse of power. Opponents argue that as long as the prosecutor’s authority for supplementary investigation, reinvestigation, and direct investigation remains, the police’s primary authority to conclude investigations remains merely formal. From a neutral perspective, the gap between institutional design and operational practice, and the lack of trust between the prosecution and police, are identified as the core causes of the controversy.

Latest Trends

In 2024–2025, discussions continue on follow-up legislation and institutional improvement for the adjustment of investigative powers between the prosecution and police. Interpretive disputes over the scope of the prosecutor’s supplementary investigation authority, the prosecution’s criteria for requesting reinvestigation of non-referred cases, and the issue of adjusting the scope of direct investigation of the six major crimes remain major issues. The police demand organizational and personnel expansion to strengthen investigative autonomy and expertise, while the prosecution maintains that supplementary investigation authority is an essential mechanism for uncovering the substantive truth of cases. In academia and civil society, the need is raised for disclosure of statistics and the establishment of an independent evaluation body to verify the empirical effects of the system’s implementation. In addition, as new types of crimes such as digital evidence, drug and organized crime, and cybercrime increase, voices are growing that the division of roles among investigative bodies must be reestablished.