SEOUL: South Korea's impeached President Yoon Suk Yeol will appear for the first time Tuesday (Jan 21) at the Constitutional Court, his lawyer said, for hearings that will decide whether to remove him from office.

South Korea was plunged into political chaos by Yoon's Dec 3 martial law declaration, which lasted just six hours before lawmakers voted it down.

They later impeached him, stripping him of his duties. He also became the first sitting South Korean president to be arrested in a criminal probe on insurrection grounds.

The country's Constitutional Court is currently holding hearings to decide whether to uphold his impeachment, and his legal team said late Monday that the suspended leader would attend.

"The President will appear at the Constitutional Court tomorrow," his lawyer Yoon Kab-keun said in a statement.

If the court rules against Yoon, he will lose the presidency and elections will be called within 60 days.

Yoon stayed away from the first two hearings last week, but the trial, which could last months, will continue even if he is absent.

Yoon has also been refusing to submit to separate questioning by the Corruption Investigation Office (CIO), the body in charge of the criminal probe into his martial law declaration.

It said it had attempted to compel him to attend but due to the "suspect's continued refusal to cooperate" they abandoned the efforts.

If Yoon is at the impeachment trial, questioning him "will be difficult" on Tuesday, a CIO official told reporters.

"RILING PUBLIC OPINION"

Yoon made his first court appearance on Saturday at a hearing on whether to extend his detention. When it was extended, hundreds of pro-Yoon protesters attacked the court building and scuffled with police officers.

The impeached president's decision to start showing up at the Constitutional Court hearing is more about inflaming his die-hard supporters than helping the judicial process along, experts said.

"Whether it's the legal representative speaking or Yoon himself speaking it's nearly the same, it's more about riling public opinon," lawyer Kim Nam-ju told AFP.

But whatever Yoon's motives, "from the perspective of the Constitutional Court judges, hearing directly from the defendant is far more significant", he said.

"The court can directly question and receive answers from them, allowing the judges to confirm the facts firsthand."

But even if Yoon starts showing up at the Constitutional Court, the fact that he is refusing to engage with the criminal investigation into his martial law will not work in his favour for his impeachment trial, said Kim.

"Refusing to comply with the warrant execution and declining to testify will gradually be considered as factors unfavourable to his case in the impeachment trial," said Kim.

"It shows they are not adhering to the legal framework."

Yoon has claimed the criminal probe is illegal and resisted arrest for weeks, vowing to "fight to the end".

Although Yoon won the presidential election in 2022, the opposition Democratic Party has a majority in parliament after winning legislative polls last year.

The Democratic Party has celebrated the president's arrest, with a top official calling it "the first step" to restoring constitutional and legal order.