On April 7, 2026, the Seoul High Court became the focal point of South Korea’s ongoing reckoning with the 12.3 martial law crisis, as it held the final hearing in the high-profile appellate trial of former Prime Minister Han Deok-su. Han, once the country’s second-in-command, now faces the possibility of spending the rest of his life behind bars after being convicted in January on charges connected to one of the most dramatic constitutional crises in modern Korean history.
The case against Han has gripped the nation, not least because of its unprecedented scope. According to Daegu Munhwa Broadcasting Corporation, Han was charged with participating in important tasks of rebellion, creating false official documents, and perjury. The charges stem from his alleged failure to prevent the illegal declaration of martial law by then-President Yoon Seok-yeol on December 3, 2024—a move that the courts have since recognized as an act of rebellion. Han was also accused of signing and then discarding the martial law declaration document, as well as giving false testimony before the Constitutional Court about his knowledge of the declaration.
Han’s first trial, held by the Seoul Central District Court’s Criminal Division 33, culminated in a stunning verdict in January 2026. The court not only found him guilty on the major charges, but also sentenced him to 23 years in prison—eight years longer than the 15-year sentence requested by the prosecution. As Newsworks reported, this made Han’s punishment one of the heaviest ever imposed on a South Korean official for rebellion-related crimes, surpassed only by sentences handed to the former president and the former defense minister.
The appellate hearing, conducted by the Seoul High Court Criminal Division 12-1, was no less dramatic. The court completed its evidence examination and heard the prosecution’s sentencing recommendation, the defense’s final argument, and Han’s own final statement. According to BBS News, the prosecution and defense clashed over Han’s actions and intentions during the crisis. The prosecution, relying on CCTV footage from the presidential office, argued that Han “did not make any real effort to prevent the declaration of martial law,” and that his calls for convening cabinet members were aimed solely at creating the appearance of procedural legitimacy. The defense countered that Han had “made constitutional efforts to persuade President Yoon through cabinet discussions to consider alternative opinions.”
Han’s legal troubles began in earnest in August 2025, when he was indicted without detention for his role in the martial law events. The indictment charged him not only with failing to stop the president’s illegal actions, but also with giving martial law a veneer of legitimacy by signing related documents and later discarding evidence. As Seoul Economic Daily detailed, Han’s perjury charge stemmed from his testimony at the Constitutional Court, where he claimed not to have seen the martial law declaration document—an assertion his own defense team later acknowledged as false.
The first trial’s verdict was historic in more ways than one. Not only did it mark the first time a former Prime Minister was detained in court for such charges, but, as noted by Newsworks, the court also explicitly defined the 12.3 martial law as a “rebellion” under the criminal code. The trial judge stated, “As Prime Minister, Han had a constitutional duty to safeguard the nation, but he chose to participate, believing the rebellion might succeed.” The court’s decision sent shockwaves through the political establishment, serving as a stern warning about the responsibilities—and liabilities—of high office.
Public attention has remained fixed on the appellate process, with legal experts speculating about whether Han’s sentence might be reduced on appeal. Han, born in 1949, would be close to 100 years old upon release if the 23-year sentence is upheld. The appellate court is expected to announce its verdict by the end of April, in accordance with the requirement that a decision be rendered within three months of the first trial’s verdict.
This case is not unfolding in isolation. The 12.3 martial law crisis triggered a series of legal actions against other top officials, including former President Yoon Seok-yeol, who faces his own appellate verdict later this month, and former Defense Minister Kim Yong-hyun. On the same day as Han’s appellate hearing, the Seoul Central District Court held the first trial’s closing arguments for Kim, who is accused of obstructing official duties and destroying evidence related to the rebellion. Kim’s trial, which began in June 2025, was delayed for nearly a year due to various legal challenges, highlighting the complexity and contentiousness of these cases.
The implications of Han’s trial extend far beyond the fate of a single official. As Seoul Economic Daily observed, the case has become a touchstone for debates about public office ethics, the rule of law, and the proper handling of rebellion charges in South Korea. The first trial’s recognition of the 12.3 martial law as a “rebellion” set a new legal precedent, one that could influence the outcomes of related cases and shape the boundaries of official responsibility for years to come.
For the public, the proceedings have been a sobering reminder of the fragility of constitutional order and the importance of vigilance in the face of executive overreach. The trials have sparked renewed calls for transparency, accountability, and the strict observance of legal processes at all levels of government. Some observers, citing past cases involving former presidents Chun Doo-hwan and Roh Tae-woo, have noted that the current trials could serve as a powerful deterrent against future abuses of power.
Meanwhile, the business community and government officials are watching closely, aware that the outcome may affect not only legal standards but also public trust in institutions. As Daegu Munhwa Broadcasting Corporation pointed out, the heavy sentences handed down in these cases underscore the judiciary’s willingness to assert its independence and uphold constitutional principles—even at the highest levels of government.
In the coming weeks, as the appellate court prepares to render its decision, South Korea finds itself at a crossroads. The resolution of Han Deok-su’s case will not only determine his personal fate but will also send a signal about the nation’s commitment to the rule of law and the responsibilities of those entrusted with public power. The eyes of the nation—and much of the world—remain fixed on Seoul’s courtrooms, waiting to see how this chapter in Korean history will close.