South Korea’s ex-president Yoon sentenced to life for martial law power grab

South Korea's former president Yoon Suk Yeol has been sentenced to life in prison after a court found him guilty of rebellion for declaring martial law in an attempt to consolidate power. The Seoul Central District Court delivered the verdict on Thursday, matching the punishment prosecutors had requested during the trial's final hearing in January. The conviction marks a historic moment in South Korean politics, as Yoon becomes the first sitting president in the country's history to be arrested and indicted.

Background

Yoon's downfall began on December 3, 2024, when he announced the imposition of martial law during a televised address to the nation. In his speech, Yoon accused the opposition of being an "anti-state den of criminals" and claimed they were trying to overthrow South Korea's democracy by impeaching members of his cabinet and blocking his budget plans. He called the declaration necessary to protect against what he described as North Korean conspiracy and anti-state forces.

The martial law decree was extraordinary in its scope. It went further than those issued by previous South Korean military dictators by suspending the National Assembly, the country's parliament. Yoon appointed Army General Park An-su as martial law commander and ordered military and police forces to enforce the measure. He instructed police to arrest lawmakers attempting to enter the National Assembly, telling them it was illegal for politicians to defy the proclamation.

The power grab was short-lived. The martial law remained in effect for only about six hours before being lifted. A group of lawmakers managed to break through military blockades surrounding the National Assembly and voted unanimously to end the measure. The rapid collapse of Yoon's attempt caught many observers by surprise, given the military resources he had mobilized.

Key Details

The conviction and sentencing

Judge Jee Kui-youn found Yoon guilty of rebellion for mobilizing military and police forces in what the court described as an illegal attempt to seize the National Assembly, arrest politicians, and establish unchecked power for a "considerable" time. The judge's reasoning focused on Yoon's deliberate use of state security forces to undermine democratic institutions.

"He found Yoon guilty of rebellion for mobilizing military and police forces in an illegal attempt to seize the liberal-led National Assembly, arrest politicians and establish unchecked power for a considerable time" – Judge Jee Kui-youn

Prosecutors had demanded the death penalty for Yoon, arguing that his actions posed a fundamental threat to South Korea's democracy and deserved the most severe punishment available. However, most analysts expected a life sentence rather than capital punishment. South Korea has not executed a death row inmate since 1997, and the country is widely seen as having a de facto moratorium on capital punishment. Additionally, Yoon's poorly planned power grab did not result in any deaths, which likely influenced the sentencing decision.

Yoon's former Defense Minister Kim Yong-hyun was also convicted of rebellion and sentenced to 30 years in prison. Yong-hyun had urged Yoon to declare martial law during a cabinet meeting shortly before the announcement and was instrumental in coordinating the military response to the declaration.

The path to conviction

Yoon was arrested on January 15, 2025, and indicted for leading an insurrection on January 26, becoming the first sitting president in South Korean history to face such charges. He was suspended from office on December 14, 2024, after lawmakers impeached him over the martial law declaration. The Constitutional Court formally removed him from office in April 2025.

During his detention, Yoon faced multiple criminal trials. In addition to the rebellion charge, he was previously sentenced to five years in prison for resisting arrest, fabricating the martial law proclamation, and bypassing a legally required full Cabinet meeting before declaring the measure. Other officials in his administration also faced consequences. Prime Minister Han Duck-soo received a 23-year prison sentence for attempting to legitimize the decree through a Cabinet Council meeting, falsifying records, and lying under oath. Han has appealed that verdict.

What This Means

The conviction represents a significant moment for South Korea's democracy and its judicial system. The country has struggled with its authoritarian past, and the case demonstrates that even sitting presidents can be held accountable for attempting to undermine democratic institutions. The speed with which lawmakers, judges, and prosecutors moved to investigate, indict, and convict Yoon reflects the strength of South Korea's democratic safeguards.

Yoon has defended his martial law declaration as an act of governance necessary to stop what he called liberal "anti-state" forces from obstructing his agenda through their legislative majority. Supporters gathered outside the courthouse during his trial, while critics demanded severe punishment. The political divisions remain evident, though the court's decision suggests that the judicial system has functioned independently of political pressure.

The case also raises questions about how South Korea will move forward. Yoon's conviction and imprisonment mark a dramatic fall for a conservative politician who was elected president in 2022. His legal troubles are far from over, as he continues to face other criminal charges and trials related to his time in office and the martial law declaration.