The protest visit came ahead of the final two hearings in Yoon’s trial this week. The court is expected to deliver its final verdict next month.

President Yoon’s brief declaration of martial law on Dec. 3 led to his impeachment by the unicameral parliament and his arrest on insurrection charges.

If the Constitutional Court upholds the impeachment, the president will be removed from office, triggering a presidential election within 60 days — a scenario that the PPP is desperately trying to prevent.

The PPP takes particular issue with Acting Chief Justice Moon’s qualifications because of his relationship with opposition Democratic party leader Lee Jae-myung, the chief organizer of Yoon’s parliamentary impeachment. Lee is also one of the strongest candidates to win the potential presidential election.

Lee and Moon know each other. After passing the bar exam in 1986, Justice Moon studied together with Lee at the Judicial Research & Training Institute, a mandatory step to becoming a judge, prosecutor, or lawyer in South Korea.

It was disclosed that the two had multiple conversations on social media in the past, which prompted the PPP to question Moon’s impartiality.

In response, Lee opted to unfollow Moon on X, while Moon deleted his X account. However, the controversy persists.

The PPP also questions Moon’s political stance, noting that he previously headed the progressive Our Law Research Association” a judicial group founded in 1989.

In addition, the governing party has taken issue with the impartiality of two other judges, Lee Mi-sun and Jung Gye-sun, who were also members of the Our Law Research Association.

The former’s spouse works for the same company as the lawyer, who represents the National Assembly in the impeachment trial, and the latter’s brother is vice chairman of a committee pushing for Yoon’s resignation, according to the PPP.

“The Constitutional Court’s bias, unfairness, and incompetence have sparked public outrage. It is telling that nearly half of people say that they do not trust the court,” Rep. Kim Gi-hyeon said at Monday’s press conference.

According to Gallup Korea on Friday, among 1,004 adult respondents, 40% disapproved of the Constitutional Court while 52% approved of it. A month ago, the disapproval rate was 31%,

The Constitutional Court has attempted to block the rising disapproval rate, reiterating that the impeachment trial would not be influenced by the personal inclinations of justices.

The Democratic Party, which holds up to 170 seats in the 300-member Assembly, also contended that the ruling party has undermined the credibility of the Constitutional Court, a cornerstone of the judicial system.

“(The PPP) is siding with actions designed to destroy the constitutional order. More accurately, the party is destroying the order itself. This is neither progressive nor conservative; this is pure destruction,” opposition leader Lee said after the PPP held a protest at the Constitutional Court last week.

Still, most opinion polls find that the majority supports Yoon’s impeachment. In the above-mentioned Gallup survey, 57% backed his impeachment while 38% opposed it.

“Whatever decisions that the Constitutional Court makes, I am concerned whether people are ready to accept it,” Shin Yul, a political science professor at Myongji University in Seoul, told UPI. “The Constitutional Court showed some operational inadequacy and lack of consistency to cause the loss of its credibility.”

However, he did not agree with the worries that the political stances of some judges would pose any serious problems in delivering the final verdict.

Currently, eight judges of the Constitutional Court are deliberating the case. The law requires the approval of at least six justices for Yoon’s impeachment to be upheld.