Prosecutors investigating the December 3 emergency martial law incident are considering transferring the investigation into President Yoon Suk-yeol's alleged “insurrection” to the Corruption Investigation Office for High-ranking Officials (CIO). It will be interesting to see if the prosecutor's Special Investigation Support Division and the police and CIO’s Joint Investigation Division can resolve the so-called “the investigation shopping” controversy that has arisen after the police and prosecutors repeatedly summoned Yoon to appear in court.

According to an interview with Kyunghyang Shinmun on December 16, the special investigation headquarters of the prosecution's emergency martial law (headed by Chief Prosecutor of Seoul High Prosecutors’ Office Park Se-hyun) is discussing handing over the investigation of Yoon in response to a request from the CIO to transfer the case. Prosecutors are reportedly concerned that Yoon could argue in a future trial that the prosecution collected evidence through an illegal investigation by refusing to hand over the case. It is also said to have considered that the police accepted the request and transferred Yoon's investigation.

However, military commanders, including former Defense Minister Kim Yong-hyun, are likely to be excluded from the transfer because the investigation is so well processed that they have already been detained or an arrest warrant was issued. Even if the prosecution transfers Yoon's case to the CIO, it does not have the authority to prosecute the president, so the prosecution would have to take over the case and indicthim again.

“We are concerned about whether it is right to leave even a small part of the violation of the law in the prosecution's investigation, including the Public Prosecution Service Act.” said a prosecutor's official, adding, “We are currently reviewing it internally and will have further discussions with the CIO.”

On December 8, the CIO requested that both prosecution and the police transfer the case. The prosecution refused, but the police formed a joint investigation headquarters with the CIOand transferred the investigation into Yoon and others. The CIO Act stipulates that “if the Chief Prosecutor of CIOrequests a transfer of overlapping investigations in light of the progress of the investigation and the controversy over the fairness of the investigation, the investigating agency shall comply.

If Yoon attends the investigative agency, he will be the first president to be investigated while still in office. Currently, Yoon can choose between the Special Investigation Unit or the Joint Investigation Unit as if he is shopping. The prosecution may be suspected of unfairness due to the fact that Yoon is a former prosecutor general, and the CIO has relatively little experience in large-scale investigations, leading to controversy over its lack of investigative power. If the investigative jurisdiction of the Special Investigation Unit or the Joint Investigation Unit is not coordinated, Yoon could attend the investigation on one of them and “sway the investigation” to confuse the entire investigation.

There are also predictions that Yoon will use the jurisdictional coordination between the Special Investigation Unit or Joint Investigation Unit as a reason for not attending.

As Yoon claimed in his December 12 statement that “the exercise of the power to declare martial law is not subject to judicial review like the exercise of the power to pardon and the exercise of diplomatic powers,” it is possible that he will refuse to appear before the prosecutors outright.

The CIO has asked the prosecutor's office to transfer the martial law case until December 18. If the prosecutors transfer the Yoon investigation to the CIO, the jurisdictional controversy would be largely resolved. However, the need for prosecutors, police, and the CIO to cooperate in the investigation remains, as the prosecution has secured the key suspects among the military officers, and the police have secured ones among the police officers.