The prosecution and the Corruption Investigation Office for High-ranking Officials are investigating suspicions involving the presidential nominees of the ruling and main opposition parties, but their investigations seem unfair.

The CIO booked Yoon Seok-youl, presidential nominee of the opposition People Power Party, again. This time, in connection with a complaint that he instructed prosecutors to document judges’ ruling tendencies when he was the prosecutor general. It marked the fourth time the agency has booked him.

Five months ago, a civic group that has made dozens of accusations against Yoon filed the related complaint with the CIO. The agency had sat on it, then suddenly took it up and booked only Yoon among six people mentioned in the complaint.

It is questionable if the CIO is trying to incriminate Yoon in some way because it failed to get satisfactory evidence from its probe into another case in which it also booked him. The case is about allegations that Yoon conspired with the opposition party to open investigations into ruling camp figures ahead of general elections last year as the top prosecutor.

A former member of the party’s election campaign committee revealed that prosecutor Son Jun-seong, an aide to Yoon when he was the prosecutor general, handed over bills of indictment against ruling camp figures to a figure who was then a former prosecutor and People Power Party parliamentary candidate, asking him to file the accusations with the Supreme Prosecutors Office to launch investigations.

The CIO seems determined to implicate Yoon among all possible suspects.

After booking Yoon over the indictment instigation allegations just three days after receiving the related complaint, the office said that whether he is guilty or not is a question to worry about later. To the office, booking Yoon mattered the most.

The four cases in which the CIO booked him amount to nearly one-third of all the cases under its formal investigation. When it requested pretrial detention for prosecutor Son, about a third of the related warrant’s content is said to concern Yoon.

The office was established to eradicate crimes by high-ranking incumbents, including the president, prime minister, lawmakers, governors, mayors, judges and prosecutors.

Obviously, the Daejang-dong scandal should be taken up by the office. Suspects face bribery and breach-of-trust charges in connection with a land development project implemented under the supervision of the city of Seongnam, Gyeonggi Province, when Lee Jae-myung, now the ruling party’s presidential candidate, was its mayor.

However, the agency left the case to the prosecution and keeps focusing on complaints targeting Lee’s rival, Yoon.

Nevertheless, as for probes targeting Yoon, it is hand in glove with the prosecution.

The inspection department of the Supreme Prosecutors’ Office confiscated a mobile phone that former and incumbent SPO spokespersons used for official use. The inspectors wanted to find clues related to the indictment instigation allegations.

The inspectors did forensics on the phone and handed over data from it to the CIO when its investigators raided the inspection department. It is questionable if the CIO asked the department to seize the cellphone to skip the difficult process of seeking an official court warrant for the seizure. The CIO’s request for prosecutor Son’s pretrial detention was rejected.

The Justice Ministry’s inspector general is said to have requested the Seoul Central District Prosecutors’ Office hand over investigation records on the school admissions scandal involving children of former Justice Minister Cho Kuk. The inspector general cites a complaint it received, but it would not be difficult to guess the real reason the ministry is inspecting the investigations. Yoon commanded investigations that dug up the Cho family’s irregularities, antagonizing Cheong Wa Dae and the ruling party. Then he became the opposition party’s presidential candidate.

Prosecutors investigating the Daejang-dong scandal seem to be operating in fear of finding evidence that could implicate the Democratic Party of Korea’s presidential nominee. They raided the Seongnam municipal government and Seongnam mayoral office belatedly. Their investigations are moving so slowly as to invite questions as to if they have the will to get to the root of the scandal. They are said to view it as difficult to hold Lee responsible for professional malpractice on the grounds that he made “policy judgment.”

The CIO and the prosecution are disregarding fairness in investigation to mount pincer attacks on Yoon.