Evidence destruction in Jang Yun-gi case nearly buried, bar association says, backing prosecutors' supplementary investigation powers

The Korean Bar Association has cited the so-called "Jang Yun-gi murder case" in calling on the National Assembly to ensure prosecutors retain a meaningful role in supplementary investigations, as lawmakers debate revisions to the Criminal Procedure Act.

In a statement issued Friday, the association said the criminal justice system must be built around two absolute principles: preventing harm to the public and uncovering the truth. "Any institution that monopolizes authority will ultimately become corrupt," it said, adding that the system must be carefully designed so that each agency operates with appropriate speed, authority and accountability, grounded in mutual checks and balances.

The association said a series of recent cases involving shoddy initial investigations, leaks of investigative secrets and suspected evidence destruction had made the need for oversight of investigative agencies and reform of the criminal justice system increasingly clear. "When any investigative agency's judgment escapes external scrutiny, the truth of a case can be buried and citizens' fundamental rights can be unjustly violated," it said.

The association then proposed measures to improve the criminal justice system, saying that legal professionals such as lawyers must be able to provide substantive support for defendants' right of defense and victims' right to remedy throughout the investigative process — not only through checks between agencies.

The association's five proposals are: designing a rational scope for supplementary investigations; introducing a full-case transfer system if supplementary investigation powers are abolished; securing legal professionals' authority to supervise and direct investigations by special judicial police officers; strengthening protections for crime victims' rights and interests; and strengthening the right to counsel.

On prosecutors' supplementary investigation powers specifically, the association said the permissible scope of direct supplementary investigations by prosecutors must be rationally designed to allow for the discovery of substantive truth and punishment commensurate with the crime, adding that the scope should be limited to non-political "everyday cases" directly tied to the lives of most citizens.

The association also said that if that approach is not adopted, supplementary investigations should at minimum be exceptionally permitted for crimes "recognized as identical" to those referred by police — meaning crimes committed simultaneously for a single purpose, crimes in a means-and-result relationship, or crimes sharing the same basic factual circumstances — in order to fill investigative gaps.

The association said the Jang Yun-gi murder case offered a clear example of why supplementary investigation powers are needed as a check: had prosecutors not conducted a supplementary investigation, a critical lapse in judgment and the destruction of evidence would nearly have gone undetected.