Former South Korean President Yoon is sentenced to life in prison for treason, imposing martial law

Seoul, South Korea – Former President Yoon Suk Yeol has been sentenced to life in prison for briefly imposing martial law at the height of the biggest political crisis in decades.

Yoon fell from office after an ill-advised attempt to win the opposition-controlled legislature declaring martial law and sending soldiers to surround the legislature on 3 December 2024.

Judge Jee Kui-youn said he found Yoon guilty of treason for joining the military and police in an illegal attempt to seize the liberal-led National Assembly, arresting politicians and establishing unchecked power for a “reasonable” time.

Yoon may appeal the sentence.

Yoon’s martial law, the first of its kind in more than four decades, backfired on South Korea’s military-backed governments when authorities periodically announced emergency decrees that allowed them to station troops, tanks and armored vehicles on streets or in public places like schools to prevent anti-government protests.

As lawmakers rushed to the National Assembly, Yoon’s military command issued a decree announcing sweeping powers, including suspending political activities, controlling the press and literature, and allowing arrests without warrants.

The decision lasted for about six hours before it was lifted after a number of lawmakers managed to break through the blockaded area by the military and voted unanimously to approve the measure.

Yoon was suspended on Dec. 14, 2024, after being prosecuted by lawmakers and officially removed by the Constitutional Court in April 2025. He has been in custody since last July while facing multiple criminal charges, the crime of sedition carries the heaviest penalty.

Yoon Kap-keun, one of the former president’s lawyers, accused Jee of issuing a “pre-determined verdict” based on prosecutors’ arguments and said “the law” had fallen. He said he will discuss with his client and the legal team whether to appeal the case.

Yoon Suk Yeol told the court that martial law was only intended to raise public awareness of how liberals are crippling state affairs, and that he is willing to respect the lawmakers if they vote against the measure.

Prosecutors say it is clear that Yoon is trying to paralyze the legislature and prevent lawmakers from putting the measure up for a vote, actions that exceed his constitutional authority even under martial law.

Announcing the decisions of Yoon and Kim, Jee said the decision to send the military to the National Assembly is important in his decision that the imposition of martial law is tantamount to treason.

“This court finds that the purpose of (Yoon’s) action was to send soldiers to the National Assembly, to block the buildings of the Assembly and to arrest important people, including the Speaker of Parliament and the leaders of the ruling and opposition parties, in order to prevent the lawmakers from meeting for the purpose or voting,” said Jee. “It has been sufficiently established that he intended to disrupt or paralyze the activities of the Legislature so that it will not be able to properly perform its duties for a long time.”

When Yoon arrived at the court, hundreds of police officers watched Yoon’s supporters gather outside the court, crying loudly as the prison bus carrying him passed by. Yoon’s critics rallied around, demanding the death penalty.

There were no immediate reports of major clashes following the decision.

The special prosecutor sought the death penalty for Yoon Suk Yeol, saying his actions threatened the country’s democracy and deserved the harshest punishment available, but many analysts expected a life sentence since the random usurpation of power did not cause harm.

South Korea has not executed a death row inmate since 1997, in what is widely seen as a freeze on the death penalty amid calls for it to be abolished.

The court also convicted and sentenced several former military and police officials involved in enforcing Yoon’s martial law, including former Defense Minister Kim Yong Hyun, who received a 30-year sentence for his key role in organizing the move and mobilizing the military.

Last month, Yoon was sentenced to five years in prison for resisting arrest, creating a declaration of martial law and skipping a full Cabinet meeting that was officially approved before announcing the move.

The Seoul High Court also convicted two members of Yoon’s cabinet in other cases. That includes Prime Minister Han Duck-soo, who received a 23-year prison sentence for trying to legitimize the decision by forcing it through a Cabinet Council meeting, falsifying records and lying under oath. Han appealed the decision.

Yoon is the first South Korean president to receive a life sentence since former military dictator Chun Doo-hwan, who was sentenced to death in 1996 for a 1979 coup, a bloody crackdown on pro-democracy protesters in Gwangju in 1980 that left more than 200 people dead or missing, and corruption.

The Supreme Court later reduced his sentence to life imprisonment, and he was released in late 1997 under a special presidential pardon. He died in 2021.