The Supreme Prosecutors’ Office has launched an inquiry into the unseemly clash between high-ranking prosecutors involved in the probe into the National Intelligence Service’s alleged meddling in the December presidential election. 

The inspection should be carried out swiftly to help prosecutors get their act together. Inspectors should first determine whether Cho Young-kon, head of the Seoul Central District Prosecutors’ Office, stonewalled the probe into the spy agency.

The allegation against Cho was made by Yoon Seok-youl, who was until last week the head of the special team investigating the NIS.

During a parliamentary audit Monday, Yoon said he sought approval from Cho on arresting three NIS agents who were found to have posted some 55,000 messages on Twitter to smear the opposition presidential candidate in the run-up to the election.

The prosecutor said he also asked for permission to press additional charges against Won Sei-hoon, the former NIS director indicted for orchestrating the spy agency’s alleged intervention in the election.

Yoon attested that Cho got furious when he suggested the need to arrest the three NIS agents and rewrite the indictment against Won. He quoted Cho as saying that “such acts would only benefit the opposition party.”

It is hard to believe that a senior prosecutor tried to impede the NIS investigation for political reasons. As Cho denies Yoon’s allegations, inspectors need to find out who is telling the truth.

They also need to verify Cho’s claims that Yoon breached laws when he arrested the NIS agents and filed a request with the court to modify the indictment against Won without approval from him.

The law on the prosecutors’ office requires each prosecutor to follow the direction and supervision of their superiors with respect to prosecutory affairs. When a prosecutor has different views from those of their superiors regarding a specific case, they can raise an objection.

The law on the spy agency stipulates that when a prosecutor investigates NIS agents, they should notify it of the probe in advance.

Cho said the Supreme Prosecutors’ Office removed Yoon from the investigation team because of his breach of the two laws. If Yoon did violate the laws, he should be punished accordingly to establish discipline for prosecutors.

Yet the SPO, while forcing Yoon to quit as chief of the probe team, stopped short of withdrawing his request to the court for modification of the indictment against Won.

This means the office rightly views the new charges brought against Won as valid. Now it is up to the court to decide whether to accept Yoon’s request or not. If it does, the prosecution will have more evidence to prove the spy agency’s systematic meddling in the December election.

The fact that three NIS agents posted 55,000 messages on Twitter to slander the opposition candidate is a matter of serious concern. Yet it would make little sense to argue that these messages affected the outcome of the presidential election, given that Twitter postings are delivered to followers only.

Now political parties need to wait for the court’s verdict. They should focus on establishing the truth and reforming the NIS, instead of escalating their battle of partisan one-upmanship and confusing the public with groundless accusations.