The prosecution indicted 13 people on Wednesday, accusing them of taking part in the presidential office’s alleged intervention in the Ulsan mayoral election.

They include Ulsan Mayor Song Cheol-ho, former Commissioner of the Ulsan Metropolitan Police Agency Hwang Un-ha and former Presidential Secretary for Civil Affairs Baek Won-woo.

As in the case of Choi Kang-wook, a presidential secretary for public office discipline, Prosecutor General Yoon Seok-youl directly made the decision to indict the 13 figures.

According to the prosecution, Hwang investigated an aide to the Ulsan mayor on tipoffs provided by Cheong Wa Dae officials to help Song, President Moon Jae-in’s old friend, win the mayoral election in 2018.

Only one person, Lee Seong-yun, head of the Seoul Central District Prosecutors’ Office, reportedly opposed the indictments. He was appointed as head of the office through a reshuffle that ousted Yoon’s closest aides, who were top prosecutors. The shake-up was carried out by Justice Minister Choo Mi-ae on Jan. 8, just six days after she assumed office.

Lee is said to have argued that an advisory panel should decide whether to indict the election-meddling suspects. Earlier, he had dawdled on whether to indict Choi. So, on Yoon’s direct instructions, prosecutors under Lee’s supervision bypassed his approval and indicted Choi on Jan. 23.

Choi was charged with issuing a false certificate of internship to the son of former Justice Minister Cho Kuk -- Choo’s predecessor. Cho resigned amid corruption allegations against his family. He himself has also been charged with power abuse and bribery.

Lee’s argument is in line with a document issued by the Justice Ministry a day earlier to prosecutors’ offices across the nation. Choo sent a document instructing prosecutors to gather internal and external opinions before deciding whether to indict suspects. As an example, the document cited an advisory panel as Lee mentioned when he opposed the indictment of Choi.

The document appears to be aimed at delaying indictments or slackening investigations in cases involving three figures close to Moon -- Ulsan Mayor Song, former Justice Minister Cho and former Busan Vice Mayor Yoo Jae-soo.

The indictment of the 13 figures reveals the prosecutor general’s intent to wrap up the probe before Feb. 3, when current midlevel and rank-and-file prosecutors are set to start their new jobs. Choo reassigned most of them Jan. 23, apparently to ground their investigations. Once the prosecutors she appointed begin work on Feb. 3, they will likely seek to change the course of the investigations and put the brakes on the indictments.

Lee is not the first top prosecutor appointed by Choo to try to obstruct indictments by Yoon’s investigators. In a meeting presided over by Yoon on Jan. 16, Sim Jae-cheol -- appointed by Choo as the new head of the anti-corruption department of the Supreme Prosecutors’ Office in the Jan. 8 reshuffle -- argued that Cho should be cleared of all charges in connection with Cheong Wa Dae’s alleged cover-up of irregularities by former Busan Vice Mayor Yoo. As senior presidential secretary for civil affairs before being appointed as justice minister, Cho ordered the suspension of Cheong Wa Dae’s inspections into bribery allegations against Yoo.

Cheong Wa Dae, the Justice Ministry and prosecutors who joined hands with them tried to undermine Yoon in many ways. They replaced prosecutors and attempted to delay indictment decisions. Some key witnesses or suspects disobeyed summons. But eventually, the suspects were indicted.

The president sought to weaken the prosecution’s investigations into those on his side, saying he has authority over personnel affairs. However, his actions only raise more suspicions as to his intent.

Now the ball is in the prosecution’s court. The public’s eyes are on the proceedings, waiting to see who if anyone intervened in the election. People expect thorough investigations and an impartial judgment. If trials proceed unfairly, calls for reinvestigations and a special counsel will be inevitable.

The ruling camp has pushed for the reform of the prosecution, criticizing it for doing politically motivated investigations, and disintegrated Yoon’s investigation teams through Choo.

She relegated top prosecutors, then midlevel prosecutors. In this process, she ignored Yoon’s opinions and requests. She even introduced a new regulation that requires the prosecution to obtain prior approval from her when it wants to form a special investigation team. This will effectively block the creation of an investigation team targeting Moon’s aides or supporters.

Many people believe the prosecution can work properly only if it can investigate powerful people independently and without political influence.

The Justice Ministry must not shake the prosecution. It should revoke measures taken to tame it under the pretext of reform.