South Korean president who declared martial law claims he ‘believes in liberal democracy’

South Korean president Yoon Suk Yeol told judges he was a “firm believer of liberal democracy” as he appeared for his impeachment trial for the first time since imposing a shock martial law decree.

Mr Yoon appeared for the constitutional court hearing to decide whether to remove him from office permanently or reinstate him after he was impeached by the National Assembly.

The president became the first sitting leader of the country to be arrested last week under a separate criminal investigation on insurrection charges for imposing martial law on 5 December and throwing the country into political turmoil.

Dressed in a navy-coloured suit with a burgundy tie, Mr Yoon entered the courtroom at 2pm on Tuesday and waited to speak before eight judges and acting court president Moon Hyung-bae.

"It’s my first time attending today, so I will speak briefly," Mr Yoon, a career prosecutor before his 2022 election as president, said after asking permission to speak.

"Since coming of age, I have lived with a firm belief in liberal democracy until this very day, and especially during my time in public service," he said.

"As the constitutional court is an institution that exists to defend the constitution, I ask the justices to consider me favorably in various respects."

Hundreds of supporters gathered outside the court in the south of the capital where a huge security arrangement was in place as the president’s appearance drew scores of supporters who protested the legal action against him.

Holding banners reading “Impeachment Invalid” the crowd chanted slogans as Mr Yoon arrived from the Seoul Detention Centre, where he is being held in a correctional service vehicle escorted by a Presidential Security Service motorcade.

Dozens of police buses were lined bumper-to-bumper on both sides of the street in front of the court to limit access to the premises hours before the start of the hearing.

Security was stepped up after a mob of angry supporters went on a rampage through the district court on Sunday and broke into the court that issued a warrant to extend his detention.

One woman was detained from outside the court for allegedly assaulting a police officer, Yonhap reported.

Lawyers of Mr Yoon have denounced the impeachment trial as a political attack against the president by opposition parties abusing their parliamentary majority and it had nothing to do with safeguarding constitutional order.

Mr Yoon is facing a charge of insurrection, which is one of the few that a South Korean president does not have immunity from and is technically punishable by death. South Korea, however, has not executed anyone in nearly 30 years.