Justice Minister Warns on Democratic Party's Prosecution Bill: Who Should Investigate Crime in South Korea?

South Korea's prosecution reform debate has increasingly become a question not simply of whether prosecutors have too much power, but of how investigative authority should be distributed without creating a different concentration of power elsewhere. Justice Minister Jung Sung-ho raised concerns about eliminating prosecutors' supplementary investigative authority, particularly when an initial police investigation is incomplete or inadequate. At the same time, supporters of the reform argue that allowing the same institution to investigate cases, choose evidence and decide whether to prosecute creates its own serious conflict-of-interest risks. The central policy question is therefore not whether police or prosecutors can be trusted absolutely, but how a criminal justice system can prevent either institution from becoming effectively unchecked.

What Is Changing Under South Korea's Prosecution Reform?

South Korea is approaching one of the largest reorganizations of its criminal justice system in decades. Legislation passed in 2026 separates investigative and indictment functions that historically existed within the prosecution service, with the new institutional structure scheduled to take effect on October 2, 2026. The existing prosecution structure is being replaced by separate bodies responsible for prosecution and serious-crime investigations.

A separate amendment to the Criminal Procedure Act passed the National Assembly on July 31, 2026, and was approved by the Cabinet on August 4. It eliminates prosecutors' remaining authority to conduct direct investigations, including supplementary investigations. Prosecutors will instead be able to request that judicial police conduct additional investigative work when they conclude that more investigation is necessary.

It is therefore slightly misleading to describe the reform as making the police the country's only investigative institution. Ordinary criminal investigations will depend heavily on police, but the new Serious Crimes Investigation Agency will separately investigate designated categories of major offenses. Special judicial police and other specialized investigative mechanisms also remain relevant within Korea's broader enforcement system.

Issue	Earlier Prosecutorial Model	New Reform Direction
Direct investigation	Prosecutors retained authority in designated cases	Separated from the prosecution function
Supplementary investigation	Prosecutors could investigate further themselves in qualifying cases	Prosecutors request additional investigation instead
Indictment	Handled by prosecutors	Remains institutionally separated from investigators
Major-crime investigations	Could involve prosecutors directly	Assigned primarily to a separate serious-crime investigative body
Main institutional concern	Concentration of investigative and prosecutorial authority	Whether investigators will receive sufficient independent scrutiny

Why Did the Justice Minister Warn About Supplementary Investigations?

Justice Minister Jung Sung-ho's concern centered on situations in which investigators overlook evidence, misunderstand a case or fail to pursue necessary investigative steps. Under the previous structure, prosecutors reviewing a transferred case could sometimes conduct supplementary investigative work themselves. Removing that authority means prosecutors generally have to send the matter back by requesting additional investigation rather than independently correcting the deficiency.

The concern is especially significant when the problem is not simply an innocent investigative mistake. If officials responsible for the original investigation are themselves compromised, repeatedly returning the case to essentially the same investigative organization may provide a weak safeguard. Critics therefore argue that some form of independent escalation mechanism is necessary.

That does not necessarily mean prosecutors themselves must retain broad investigative authority. The narrower question is whether prosecutors need limited corrective powers, whether another independent agency should perform that function, or whether particularly problematic cases should automatically be transferred outside the original investigative chain.

A safeguard against police misconduct does not automatically have to be prosecutorial investigation. The important requirement is that investigators cannot effectively review their own misconduct when there is credible evidence that the original investigation was compromised.

Jung continued raising concerns about victim protection as the legislation advanced. After completion of the legislation stripping prosecutors of investigative authority, he submitted a resignation letter on August 18, 2026, reportedly saying that implementation of the new criminal justice system should be completed under new leadership.

Why Police Misconduct Is a Real Concern

Concerns about relying excessively on police investigators are not purely theoretical in South Korea. Several prominent cases have raised questions about whether police relationships, institutional loyalty or local connections can interfere with investigations. Those cases do not demonstrate that the police organization as a whole is corrupt, but they illustrate why independent review mechanisms matter.

The 2026 Gwangju case: A police officer was accused of attempting to conceal or destroy evidence connected to a murder case involving the son of another police officer, generating renewed debate about internal conflicts of interest.
The Burning Sun scandal: Investigations uncovered allegations of inappropriate relationships between entertainment businesses and police officials. A senior police officer was later indicted over allegations involving attempts to cover up irregularities associated with nightlife businesses.
The Sinan salt farm abuse cases: Investigations into forced labor exposed serious failures involving some local officials and police. In a particularly troubling episode, a victim who sought help from local authorities was reportedly returned to the environment from which he was attempting to escape.

These cases demonstrate a structural problem that can arise whenever the institution responsible for investigating misconduct has personal, organizational or regional connections to the suspected offenders. The danger is particularly acute when the alleged wrongdoing involves law-enforcement personnel themselves. An investigative system therefore needs a reliable method for removing conflicted investigators from a case rather than simply hoping internal supervision will work.

At the same time, individual corruption cases should not be generalized into the claim that police nationwide operate as a single corrupt organization. Some of the same scandals also involved police investigators uncovering misconduct committed by other officers. Institutional design should account for both possibilities: misconduct within the police and legitimate police efforts to expose it.

Why Giving Prosecutors Broad Powers Creates Different Risks

The opposite argument is that restoring or preserving expansive prosecutorial investigation powers can produce another form of concentrated authority. An institution that determines which allegations deserve investigation, gathers evidence, selects investigative targets and later decides whether those same targets should be prosecuted possesses substantial control over the entire criminal process. That arrangement can be efficient, but efficiency and accountability are not necessarily the same thing.

A prosecutor who develops an investigative theory may also become institutionally committed to proving that theory. Independent review becomes more difficult when the organization evaluating whether evidence justifies prosecution is substantially the same organization that assembled the case. Critics of Korea's traditional prosecution system have long argued that this concentration created opportunities for selective investigations and politically controversial exercises of prosecutorial discretion.

International assessments have also continued to identify challenges surrounding prosecutorial integrity and accountability in Korea. Those concerns do not establish that prosecutors are inherently less trustworthy than police. They reinforce the broader principle that no law-enforcement institution should be designed on the assumption that its officials will always exercise their authority correctly.

Potential Failure	When Police Dominate Investigation	When Prosecutors Control Investigation and Prosecution
Conflicted investigator	Police may protect colleagues or connected individuals	Prosecutors may protect colleagues or institutional interests
Ignored evidence	An incomplete investigation may reach prosecutors	Investigating prosecutors may decide what evidence to pursue
External correction	Difficult if review simply returns the case to the same investigators	Difficult if investigation and charging decisions remain within one institution
Political misuse	Possible through control or influence over policing	Possible through selective investigations or charging decisions

Why Korean Prosecutors Historically Became So Powerful

The unusual relationship between Korean police and prosecutors cannot be understood without its historical background. After liberation from Japanese colonial rule in 1945, the new authorities inherited a police organization containing significant institutional continuity from the colonial period. Distrust of police misconduct and concerns about human-rights abuses were therefore important parts of the post-liberation debate about who should control criminal investigations.

The emerging prosecution service consequently obtained a strong supervisory position over police investigations. When Korea's Criminal Procedure Act was established in the 1950s, prosecutors occupied the superior position in the investigative hierarchy and could direct judicial police officers. Protecting citizens from police abuses was among the historical arguments used to justify prosecutorial supervision.

That history explains why arguments for powerful prosecutors were not necessarily irrational when the system was created. However, historical justification does not automatically establish what the optimal institutional structure should be almost eight decades later. Both the police and prosecution have changed substantially, while Korea's democratic institutions, courts and oversight bodies have also developed.

History can explain why an institution acquired extraordinary powers without proving that the same distribution of authority must remain permanent. Modern reform should evaluate current risks rather than treating arrangements created under post-liberation conditions as untouchable.

Do Other Democracies Separate Investigation and Prosecution?

There is no single democratic model in which police investigate everything and prosecutors merely appear in court. Prosecutorial involvement varies considerably between legal systems. In some countries prosecutors supervise investigations closely, while in others police exercise much greater operational independence and prosecutors primarily evaluate cases for charging and trial.

South Korea's traditional system was nevertheless notable for the particularly strong combination of prosecutorial investigative authority and charging authority. Comparative legal research has described the Korean model as one in which prosecutors historically became deeply involved in investigation while also controlling prosecution. That combination can reduce coordination problems, but it can also weaken the institutional separation between evidence gathering and the decision to prosecute.

Countries also compensate for different allocations of authority through different safeguards. Judicial review, independent police-complaints bodies, inspectors general, parliamentary scrutiny, special prosecutors and independent anti-corruption agencies can all serve functions that cannot be understood simply by comparing whether a country's prosecutors technically possess investigative authority.

For that reason, saying that another democracy gives prosecutors investigative powers does not by itself prove Korea should do the same. Conversely, saying that another country separates prosecution from investigation does not prove that simply copying that separation will succeed in Korea. The effectiveness of the surrounding accountability system matters as much as the formal division of power.

Could an Independent Investigative Agency Be the Alternative?

The debate is sometimes presented as a choice between police investigation and prosecutorial investigation, but those are not the only available models. Korea's reforms already move partly beyond that binary by establishing a Serious Crimes Investigation Agency responsible for designated major offenses. This creates the possibility of assigning sensitive investigations to investigators who are institutionally separate from both ordinary police and the body making indictment decisions.

An independent investigative mechanism could be particularly useful when police officers themselves are suspected of obstructing an investigation. The reverse principle should also apply when members of the prosecution or new prosecution institutions are suspected of misconduct. An agency cannot function as a genuine counterweight if its jurisdiction or leadership leaves it dependent on the institution it is supposed to investigate.

However, creating another agency does not automatically solve the problem. A new organization can eventually develop its own institutional interests, political vulnerabilities and internal culture. The question then becomes who can investigate the investigators of the investigators.

Police misconduct cases could trigger mandatory external referral under defined conditions.
Misconduct involving prosecution officials could be assigned outside the prosecution hierarchy.
Serious disputes over investigative obstruction could receive independent judicial review.
Case transfers and rejected supplementary-investigation requests could be recorded and auditable.
Victims could receive a meaningful procedure for challenging unjustified termination of investigations.

What Would Effective Checks and Balances Look Like?

A functioning system does not need one permanently dominant law-enforcement institution. It needs overlapping safeguards that make misconduct more difficult to conceal. Separating investigation and prosecution can contribute to that goal, but separation works only when prosecutors have access to sufficient evidence to assess charges and investigators cannot simply ignore legitimate requests without consequences.

One possible approach is to permit prosecutors to identify deficiencies and formally request supplementary investigation while creating an independent escalation process if investigators repeatedly refuse, delay or inadequately perform that work. Another possibility is automatically transferring disputed cases to a different investigative unit or independent agency where credible conflicts of interest exist. Judicial intervention could provide an additional safeguard in especially serious disputes.

Safeguard	Purpose
Independent case transfer	Prevents conflicted investigators from retaining control of sensitive cases
Recorded supplementary requests	Creates accountability when investigators fail to address missing evidence
External review	Allows disputed investigative decisions to be examined outside the original institution
Judicial oversight	Places coercive investigative measures under an institution separate from investigators
Victim challenge procedures	Provides a remedy when authorities prematurely close or neglect a case
Independent misconduct investigations	Reduces the risk of police or prosecutors effectively investigating themselves

Transparency is another important element. If prosecutors request additional investigation and investigators refuse or fail to complete it adequately, policymakers need data showing how often that occurs and what happens afterward. The same transparency should apply to prosecutorial charging decisions so that separation of powers does not produce accountability on only one side of the criminal justice process.

Such a model treats police, prosecutors and independent investigators as institutions requiring reciprocal oversight rather than as competitors fighting for exclusive authority. It also avoids framing reform around the assumption that corruption within one organization means another organization deserves unrestricted power.

The Debate Is About Institutional Design, Not Choosing a Trusted Side

The strongest argument against eliminating prosecutors' supplementary investigative powers is that a defective or compromised police investigation needs somewhere genuinely independent to go. Cases involving alleged police interference show why returning a problematic investigation to essentially the same chain of command can be inadequate. That concern deserves a structural answer rather than dismissal.

The strongest argument for separating prosecution and investigation is equally significant. Giving prosecutors the ability to initiate investigations, determine investigative strategy and then decide whether the resulting case should be prosecuted concentrates several consequential decisions within the same institution. Historical experience with prosecutorial power provides its own reasons for demanding oversight.

The choice therefore does not have to be between trusting the police and trusting prosecutors. South Korea can separate investigative and prosecutorial functions while creating independent mechanisms capable of intervening when police investigations fail, and it can subject prosecutors and new investigative bodies to comparable external scrutiny. The most resilient criminal justice system is one designed on the assumption that any institution can fail and that another genuinely independent institution must be capable of detecting and correcting that failure.

As the new system approaches its October 2026 implementation, its success will depend less on which institution loses a particular power than on whether investigators, prosecutors and oversight bodies can meaningfully check one another. That is the central checks-and-balances question behind Korea's prosecution reform debate.