A South Korean court sentenced former President Yoon Suk Yeol to life imprisonment for masterminding an insurrection through his declaration of martial law in December 2024. The Seoul Central District Court, presided over by Judge Jee Kui-youn, found Yoon guilty of deploying troops to parliament and attempting arrests, actions that subverted the constitutional order and incurred enormous social costs.

The dramatic events trace back to the night of December 3, 2024, when Yoon, a conservative leader facing political gridlock with an opposition-controlled National Assembly, declared martial law to counter what he called "anti-state forces." Troops were sent to block lawmakers from entering the assembly, and orders were issued for the arrest of politicians and judges. The decree lasted only hours before parliament voted to lift it, sparking immediate backlash.

Yoon's move led to his impeachment by the National Assembly on December 14, 2024, upheld unanimously by the Constitutional Court on April 4, 2025, removing him from office. A snap presidential election followed in June 2025, won by Democratic Party leader Lee Jae-myung. Yoon, aged 65, lost presidential immunity and faced multiple criminal trials, including this insurrection case that began in April 2025.

Prosecutors sought the death penalty, the maximum under South Korean law for insurrection, but the court opted for life imprisonment, citing the gravity of the offense while noting the plan's lack of meticulous preparation and limited use of force. The ruling also sentenced former Defense Minister Kim Yong-hyun to 30 years and other officials to lesser terms. Judge Jee emphasized that Yoon led officials and troops in criminal activities, fundamentally damaging democracy.

Yoon has denied wrongdoing throughout, maintaining that he acted within presidential authority to address opposition obstruction and alleged election irregularities. His defense team called the verdict evidence-deficient and filed an appeal shortly after. As of early March, appeal proceedings were underway in related cases, with Yoon remaining at the Seoul Detention Center.

The sentencing deepened divisions in South Korea, the first for an elected president in its democratic history. Supporters rallied outside the court demanding his release, while critics, including Democratic Party figures, labeled it a threat to the nation's foundations. President Lee praised the people's role in thwarting the martial law bid. South Korea has not executed anyone since 1997, making life terms effectively permanent, absent parole after 20 years.

Yoon faces additional trials on charges like abuse of power and obstruction, where he has already received shorter sentences, some also under appeal.