South Korea's Supreme Court upholds prison sentence for Yoon in first martial law case

South Korea’s Supreme Court upheld a seven-year prison sentence for former President Yoon Suk Yeol in the first case related to his brief imposition of martial law to reach the country’s highest court. The ruling was final and upheld an earlier April decision by the Seoul High Court.

The court found Yoon guilty of infringing on cabinet members’ right to deliberate before he declared martial law, falsifying parts of the official proclamation to cover up a procedural lapse, destroying the document afterward, and deploying presidential security forces to illegally resist law enforcement efforts to arrest him after his impeachment.

Martial law lasted only hours in 2024. Lawmakers later broke through a blockade of heavily armed troops and police at the National Assembly and voted to repeal it, requiring Yoon’s cabinet to lift the measure.

Yoon was detained at the time of the ruling and did not attend. While the Supreme Court decision concluded this case, he remains involved in other trials and has appealed a separate, more serious life sentence related to charges including rebellion.

Yoon’s legal team said it expressed “deep regret” over the Supreme Court’s ruling, while noting that it believed the justices concluded the case without sufficient review. The Supreme Court’s stance aligned with findings from South Korea’s Constitutional Court, which had previously removed him from office in April 2025, concluding the martial law decree lacked legal grounds and failed to follow required procedures.