Prosecutors searched Cheong Wa Dae in connection with suspicions over its abruptly suspended inspection of irregularities involving former Busan Vice Mayor Yoo Jae-soo.

They also vowed a thorough investigation into suspicions about Cheong Wa Dae’s intervention in a local mayoral election in Ulsan.

Following this, leader of the ruling Democratic Party Lee Hae-chan raised the possibility of getting a special counsel appointed to investigate the cases and possibly the prosecution. He urged the prosecution to create a joint investigation team with the police and conduct investigations together with them. “The party will not sit idle,” he said.

A spokeswoman for Cheong Wa Dae warned the prosecution and news media on Tuesday, saying “a law banning the prosecution from disclosing suspicions took effect Sunday.”

Lawmakers of the ruling party bashed the prosecution, calling its investigations “selective,” “biased” and “an act of politics.” They argued, that is why prosecution reforms are inevitable.

They say existing legal systems have no means to reform the prosecution lest its investigations go too far. They insist the prosecution is resisting reforms. But the reality is that they are trying to sweep all suspicions under the carpet.

Their threats to the prosecution are absurd and concerning. They should not forget that Cheong Wa Dae is at the center of suspicions, and any attempt to pressure the prosecution runs the risk of causing misunderstandings and amplifying suspicions.

In July, President Moon Jae-in told newly appointed Prosecutor General Yoon Seok-yeol to sternly investigate irregularities involving figures close to the president, no matter where they work -- at Cheong Wa Dae, government or in the ruling party.

The suspicions involving the former Busan vice mayor and Ulsan mayoral election require thorough investigation.

Meanwhile, conflicts between the prosecution and police are growing. When a former Cheong Wa Dae inspector suspected of involvement in meddling in the Ulsan election was found dead, the police secured his mobile phone. A day after his death, the prosecution searched Seocho Police Station in Seoul and seized the mobile phone, and started a forensic examination. The police department asked the prosecution to seek a court warrant to retrieve it, but the request was rejected.

When it comes to the election-meddling suspicions, the police is as good as a suspect. The former Ulsan mayor was not the only opposition party candidate investigated by the police. Three other opposition party candidates in South Gyeongsang Province -- two seeking reelection in Sacheon and Yangsan and one in Changwon -- were found to have been also investigated by the police before elections.

At least in connection with the Ulsan election scandal, the police and Cheong Wa Dae are suspected accomplices who need to be investigated. They are not in a position to warn the prosecution or interfere in investigations.

Cheong Wa Dae announced the results of an internal probe Wednesday. Its spokeswoman said an official under the presidential secretary for civil affairs came across “another public official” on a campsite and that he received a tip-off. But it did not disclose the identity of the informant.

However, the media found that the informant was Song Byung-gi, currently Ulsan vice mayor and one of the few figures closest to the president. The Ulsan mayor was elected last year by defeating an opposition party candidate and incumbent mayor.

Song told a news outlet that he gave a tip-off “because the government demanded it.” The presidential office must clarify whether the official obtained the tip-off by demanding it from the informant. This will be an important barometer which can tell if Cheong Wa Dae meddled in elections. It needs to be investigated.

Hwang Un-ha, commissioner of Ulsan Metropolitan Police Agency at the time of the police investigations in question, assigned the job of leading the probe to a police lieutenant with long-time ties to a person who accused the Ulsan mayor. The police officer had phone conversations with the accuser 535 times for about a year from April 2017 to May 2018, nearly a month before the local elections. He even provided information on the investigation to the complainant.

This vividly shows that new problems can arise when the police are empowered to investigate independently from the prosecution and a new agency investigates high-ranking officials exclusively under the pretext of prosecution reforms.