More than 40% of cases referred by police to prosecutors and subsequently disposed of underwent supplementary investigation, data showed. Observers say supplementary probes are essential for prosecutors to determine whether to indict suspects.
According to the Ministry of Justice on Wednesday, the Supreme Prosecutors' Office analyzed case processing at 12 prosecutors' offices nationwide as of April. Of 55,174 referred cases, supplementary investigations were conducted in 25,152, accounting for 45.6% of the total.
The Supreme Prosecutors' Office compiled the data by selecting 12 frontline offices with the highest volume of referred cases. Supplementary investigation refers to cases involving additional questioning of suspects or witnesses, analysis of communications records, preparation of investigation reports, or requests for preservation of assets for forfeiture. The proportion of cases in which prosecutors formally requested supplementary investigation by police stood at about 10.7% last year — lower than the share of cases in which prosecutors conducted supplementary probes themselves.
The Ministry of Justice on the same day released a casebook of notable supplementary investigations involving women, children and people with disabilities, emphasizing that supplementary probes play a critical role in criminal investigations. The casebook includes 20 cases that have drawn significant public attention, including the "Haedeun-i case," the "Saekdongwon case" and the "Busan roundhouse-kick case."
The casebook also features the 2018 "Sejong City group sexual assault case." Of the police investigation at the time, the ministry said, "When the suspects flatly denied the charges, police neglected to interview witnesses who could rebut them or to secure objective circumstantial evidence." It added, "Prosecutors listened to the pleas of children with poor communication skills, intellectually disabled victims and sexual crime victims who had been subjected to gaslighting (psychological domination), faithfully reinforcing evidence and legal reasoning to uncover the truth of the crimes." After four months of supplementary investigation, prosecutors brought the suspects to trial seven years after the incident.
