On June 17, President Moon Jae-in chose Yoon Seok-yeol (59, 23rd Class of the Judicial Research and Training Institute), the chief of the Seoul Central District Prosecutors' Office to succeed Moon Moo-il as prosecutor general. Yoon is five classes behind Moon. If Yoon is appointed as the new prosecutor general following a confirmation hearing at the National Assembly, he will be the first to be appointed prosecutor general without any experience of leading a high prosecutors' office. This will be a first in 31 years since the term of the prosecutor general was set in 1988.

Yoon was responsible for the investigation of Park Geun-hye and Choi Soon-sil for their abuse of state authority, which eventually led to the arrest and impeachment of the former president. After President Moon Jae-in entered office, Yoon contributed to the arrest of former President Lee Myung-bak and led the investigation on the abuse of court authority by the Supreme Court under Chief Justice Yang Seung-tae. By picking Yoon, President Moon sent out a message that he remained firm in his determination to root out long-established irregularities.

Cheong Wa Dae spokesperson Ko Min-jung said in a briefing, "Yoon has the trust of the people as well as the prosecutors for his successful investigation of the abuse of state authority and deep-rooted irregularities carried out with his excellent leadership and determination for reforms as the head of the Seoul Central District Prosecutors' Office." She further said, "We expect Yoon to root out various corruption and irregularities that still remain in our society and finely complete the task of reforming the Prosecution Service and its organization, which this age demands."

Yoon served as the head of departments one and two of the Central Investigation Division at the Supreme Prosecutors' Office and as the director of Special Investigations Division 1 of the Seoul Central District Prosecutors’ Office. He then led a special investigation team that looked into the online comments posted by the National Intelligence Service in 2013, the first year that former president Park Geun-hye entered office. At the time, he stood up to the justice minister, Hwang Kyo-ahn (currently the leader of the Liberty Korea Party) and argued that the state should arrest Won Sei-hoon, former director of the National Intelligence Service, for violating the Public Official Election Act, but was later demoted to the Daegu High Prosecutors' Office and the Daejeon High Prosecutors' Office. He returned as the head of investigations in the team of special prosecutor Park Young-soo and investigated the abuse of state authority in 2016, and eventually arrested former president Park, Choi Soon-sil and Lee Jae-yong, vice chairman of Samsung Electronics. After he was appointed as the chief of the Seoul Central District Prosecutors' Office, he arrested former president Lee Myung-bak and Yang Seung-tae, former chief justice of the Supreme Court.

President Moon's appointment of Yoon reflects his determination to continue his efforts to eradicate long-established irregularities even in his mid term. By appointing a "heavyweight prosecutor general," who has strong control over the organization and has the trust of the president, the president may try to silence the opposition within the Prosecution Service on the adjustment of investigative rights with the police and to strengthen his power over state administration, which can easily weaken. Eyes are on what kind of attitude Yoon will show on reforms within the Prosecution Service, which is a major reform task of the incumbent government. When Yoon was in charge of special investigations, he strongly opposed reform measures, such as the abolition of the central investigation division in the Supreme Prosecutors' Office and the adjustment of investigative rights between the police and the Prosecution Service.

The radical appointment of Yoon, which ignored seniority among prosecutors, is expected to bring a massive generation shift in the Prosecution Service. According to the common practice, the current heads of the six high prosecutors' offices, who stand above Yoon in seniority, and the heads of prosecutors' offices who were in the same class or previous classes at the Judicial Research and Training Institute will have to step down. But there have been criticism that such a practice is the legacy of an authoritarian Prosecution Service and reflects gang culture, and Yoon is also older than most of his senior prosecutors, so the appointment of Yoon may actually allow the prosecutors to a break away from such practices.