Yoon lawyers vow constitutional challenge to top court’s ruling

The Supreme Court’s decision, delivered Thursday, upheld an earlier appeals court sentence of seven years in prison for Yoon on charges that included obstruction of justice, abuse of power, and falsifying public documents. The court found that Yoon had directed his security detail to prevent investigators from executing a warrant to detain him in January 2025, after his failed martial law bid the previous month.

“The lower court’s judgment contained no errors, such as exceeding the bounds of the principle of free evaluation of evidence in violation of logic or the rules of experience, or misapplying the relevant legal principles,” the presiding judge said in announcing the ruling.

The obstruction verdict stemmed from the aftermath of Yoon’s decision on Dec. 3, 2024, to impose martial law. In addition to the obstruction charges, the former president was convicted of violating the rights of nine Cabinet members by not calling them to an advance meeting to review his martial law plan. Other charges included revising the martial law proclamation after it was lifted to disguise procedural flaws, discarding the document, ordering the distribution of a press statement containing falsehoods, and restricting access to a former military commander’s phone call records.

An appeals court had increased Yoon’s sentence from five years to seven in April, less than the 10 years recommended by a special counsel team. The Supreme Court upheld the lower court’s conviction on all charges but one related to the false proclamation, a charge the court did not uphold.

Yoon, who has been in custody since July 2025, was not present for the Supreme Court hearing — a final appeal ruling does not require the defendant to attend — but he watched the broadcast on a cellphone while at the Seoul High Court for the insurrection trial hearing. Judges at that trial briefly adjourned to allow him to hear the verdict, and Yoon gave a wry smile when it was read. The Supreme Court hearing was broadcast live despite his objections.

Yoon’s main trial on charges of leading an insurrection through the martial law bid remains ongoing at the appellate level after a lower court sentenced him to life in prison. In total, Yoon faces eight separate trials, including proceedings related to his wife’s alleged corruption and the alleged cover-up of a Marine’s death.

Immediately after the Supreme Court ruling, Yoon’s lawyers announced they would challenge its constitutionality.