Over 60,000 Cases Sent Back for Supplementary Investigation in First Half of 2026; 100,000 Unsolved Cases Piling Up

In the first half of this year, the number of cases sent back by the prosecution to the police with requests for supplementary investigation exceeded 60,000.

During the same period, more than 100,000 cases were registered as unsolved by the police, raising concerns that investigation gaps could lead to greater harm to the public.

According to data submitted by the National Police Agency to Representative Kim Jae-seop of the People Power Party, the number of cases the prosecution sent back to the police with requests for supplementary investigation from January to June of this year reached approximately 65,900.

The number of supplementary investigation requests reached a record high of 110,600 last year. Compared to 2021, the first year the system was implemented, this figure has increased by over 27% in four years, showing a continuous upward trend.

With the ruling party pushing for legislation to abolish the prosecution and strip it of its supplementary investigation powers, critics argue that if the bill passes as is, the only remaining means to check police investigations would be the right to request supplementary investigations.

While the right to request supplementary investigations and the right to conduct supplementary investigations share the same purpose—addressing insufficient legal interpretation and lack of evidence during the police investigation phase—the two differ in practice. Supplementary investigation involves the prosecution directly investigating cases referred by the police, whereas a request for supplementary investigation involves the prosecution returning the case to the police to demand further action without conducting the investigation itself.

In the recent Jang Yoon-gi case involving the murder of a high school girl in Gwangju, allegations of poor investigation and cover-ups, including claims of the police protecting their own, emerged. As the prosecution secured key evidence that was nearly covered up through its own supplementary investigation, arguments are being made that the right to conduct supplementary investigations should not be abolished, leaving only the right to request them.

Furthermore, it was recently revealed that the Seoul Suseo Police Station neglected a case for over four years after receiving a request for supplementary investigation from the prosecution, only referring it late, just one month before the statute of limitations expired. This has amplified calls to maintain the prosecution's right to conduct supplementary investigations.

Meanwhile, the number of unsolved cases that the police have failed to resolve on their own has exceeded 200,000 annually for four consecutive years, with the figure surpassing 102,000 as of June this year.

Reported by Kim Taewon | Video by Na Hong-hee | Graphics by Lee Jung-ju | Produced by SBS Digital News
※ Please note: This article was translated by AI and may contain errors.