In a significant political development in South Korea, the main opposition party submitted a motion on Thursday, December 26 to impeach Acting President Han Duck-soo. The move comes amid increasing tensions over the failure to fill three vacant seats in the Constitutional Court, which are crucial as the court prepares to review the rebellion charges against President Yoon Suk Yeol. These charges stem from Yoon's controversial decree to impose martial law on December 3, which triggered an ongoing political crisis in the country.

The vacant positions in the Constitutional Court have stalled, exacerbating the political impasse between Yoon’s conservative party and the liberal opposition. As the court prepares to deliberate on whether to reinstate or dismiss Yoon, the Democratic Party is pushing for the immediate appointment of justices. However, Han Duck-soo, in a televised address, reiterated his stance that he would not appoint any justices without bipartisan consensus.

The opposition-controlled National Assembly passed motions urging Han to make the appointments, criticizing his calls for bipartisan consent as a refusal to act. National Assembly Speaker Woo Won Shik stated that Han’s inaction violated the National Assembly's right to select Constitutional Court justices. Han’s decision to withhold appointments has intensified the standoff, with opposition parties accusing the conservatives of attempting to delay the judicial process to protect Yoon's presidency.

Yoon’s presidency was suspended following his impeachment on December 14 due to his failed power grab during the martial law attempt. However, for his presidency to be formally terminated, at least six out of nine Constitutional Court justices must vote to remove him. The three vacant seats on the court are seen as crucial to the outcome of the case, as a full bench of justices would be more likely to reach a conclusive verdict.

According to South Korea’s Constitution, the National Assembly selects three of the court’s nine justices. While the presidential appointments for these positions are typically procedural, the Democratic Party argues that Han’s refusal to act is hindering the court's work. The legal ambiguities surrounding the impeachment of an acting president could further complicate the situation. While most South Korean officials can be impeached with a simple majority, impeaching a president requires a two-thirds majority, a threshold that the Democratic Party could struggle to meet without support from other parties.

Yoon, who has largely avoided answering questions from law enforcement about the rebellion charges, has also blocked searches of his office. Meanwhile, several military commanders involved in the martial law attempt have been arrested, and the controversy surrounding Yoon’s decree has sparked wider debates about political abuse in South Korea’s government.

In the event of Han Duck-soo’s impeachment, Choi Sang-mok, the deputy prime minister and finance minister, would be next in line to serve as acting president. However, the impeachment vote could face legal challenges over which standards should apply to an acting president.

The situation remains fluid, with the Constitutional Court set to hold a pretrial hearing in Yoon’s case on December 27. If Han is impeached, it could further exacerbate South Korea’s political paralysis, already affecting the country’s diplomacy and financial markets.