South Korea begins criminal insurrection trial of ousted president Yoon

The martial law attempt, which lasted about six hours before Yoon backed down in the face of parliamentary opposition and public protests, plunged the country into months of turmoil and led to the Constitutional Court removing him from the presidency this month for violating constitutional powers.

After departing his house in a motorcade on Monday, Yoon, who has denied all charges against him, entered a courtroom at the Seoul Central District Court, wearing a dark navy suit and red tie.

At the start of proceedings, prosecutors presented their case by arguing Yoon lacked the legal grounds to declare martial law and accused him of trying to paralyse state institutions such as parliament.

"The defendant ... made it impossible for constitutional institutions to exercise their authority based on an unlawful declaration," the prosecution said.

Yoon, who was the country’s chief prosecutor before becoming president, spent about 40 minutes in the morning refuting the prosecution’s allegations.

“Martial law is not a coup d’etat,” Yoon said, adding that he had no intention of paralysing the country, but that martial law was needed to alert the people to how the majority opposition party was stonewalling government by impeaching more than 20 officials, including the Board of Audit and Inspection chief, which he saw as a dangerous threshold.

“This was a peaceful ‘message martial law’ to the nation… I knew this martial law would end within half-a-day, a day,” Yoon said.

Yoon said although he had communicated this intention to ex-defence minister Kim Yong-hyun, military officials carrying out the order seemed to have overstepped it because they are used to training for martial law under different guidelines.

INSURRECTION CHARGE

Two senior military officers are expected to take the witness stand in the afternoon.

One of them, Cho Sung-hyun from the army's capital defence command, already testified at the Constitutional Court in February that he was ordered to send troops to "drag" lawmakers out of parliament during Yoon's martial law order.

Yoon denied this allegation.

The martial law declaration, which cited the need to root out "anti-state" elements, was lifted six hours later after parliamentary staffers used barricades and fire extinguishers to ward off special operations soldiers trying to enter parliament, where lawmakers voted to reject martial law.

The charge of insurrection faced by the impeached leader is punishable by life imprisonment or even death, although South Korea has not executed anyone in decades.

Yoon's martial law declaration on December 3 shocked South Koreans, and created chaos in all areas of society, the economy and foreign policy, the Constitutional Court said when ruling to remove him from office.

The upheaval has further exposed deep social rifts between conservatives and liberals and stepped up pressure on institutions and the military, which had found itself in a quandary over whether to enforce martial law.

The former president returned to his private home on Friday from the official residence, with crowds of conservative supporters turning out to greet his motorcade.

He remains defiant and has pledged to "stand by" his supporters. The opposition Democratic Party slammed Yoon on Monday as delusional for not making any sincere apology.

The country will now hold a snap election on June 3. Questions remain over whether Yoon might still play a role.

Lee Jae-myung, the opposition leader who is leading presidential polls, visited on Monday a start-up that develops artificial intelligence chips, pledging to ease regulations with aggressive investments in the AI industry.