Yoon Suk Yeol's criminal trial begins over martial law declaration

Former South Korean president faces insurrection charges in landmark courtroom drama.

Police stand guard in front of pro-Yoon supporters waiting for the arrival of former South Korean president Yoon Suk Yeol, whose image is seen on a flag, outside the Central District Court in Seoul on April 14, 2025. Photo by Anthony Wallace/AFP

By Anna Fadiah and Hayu Andini

The criminal trial of former South Korean president Yoon Suk Yeol began Monday, marking a historic moment in the country's political and judicial history. The focus of the trial is Yoon's controversial attempt to declare martial law in December last year—a move that led to his impeachment and arrest. The criminal trial of Yoon Suk Yeol centers on insurrection charges, making it one of the most serious legal proceedings against a former leader in modern South Korean history.

Yoon appeared in person at the Seoul Central District Court to answer charges that he unlawfully ordered soldiers to intervene in the National Assembly to maintain his hold on power. His trial follows a swift political downfall that stunned even his critics, culminating in his impeachment, arrest, and removal from office.

A president on trial for insurrection

Yoon's short but turbulent tenure came to an end earlier this month, when lawmakers voted to formally remove him from the presidency. His actions on December 3, when he briefly declared martial law, had sparked outrage across political lines. Armed soldiers were sent to the National Assembly, apparently on Yoon’s orders, in a direct challenge to South Korea’s democratic norms. That event is now central to the criminal trial of Yoon Suk Yeol, which could lead to a life sentence or even capital punishment if he is found guilty.

During Monday’s hearing, Yoon sat quietly as the presiding judge addressed him as "former president." The courtroom was packed with media and observers, signaling the immense public interest in the case. Yoon was asked to confirm his name, date of birth, and address—routine questions that still held symbolic weight given the defendant’s former role as the nation's leader.

Military witnesses take the stand

Prosecutors are building their case around the testimonies of high-ranking military officers, two of whom were scheduled to appear during this week's proceedings. One of the witnesses reportedly told investigators that top commanders had directed him to “drag out the lawmakers gathered in the National Assembly to lift the martial law.” Such testimony could prove crucial in establishing that Yoon ordered a military intervention against the legislature.

Despite Yoon’s decision to rescind the martial law order within hours, lawmakers had already taken action. Many of them reportedly climbed over barricades and defied armed guards to assemble in the National Assembly. Once inside, they passed a vote that nullified Yoon’s declaration and initiated the impeachment process.

A long road ahead in the courtroom

Legal experts believe that the criminal trial of Yoon Suk Yeol will be complex and time-consuming. Attorney Min Kyoung-sic, who has no direct involvement in the case, told AFP that the court is likely to take months before issuing a verdict.

"The first verdict is likely to be delivered around August, but the case involves around 70,000 pages of evidence and numerous witnesses. So if deemed necessary by the court, the trial may be extended," Min explained.

This projection has drawn comparisons to the legal saga of Park Geun-hye, who was impeached in 2016. Her case took more than four years to reach a final judgment by the Supreme Court in 2021. That precedent suggests Yoon’s trial could stretch well into next year, especially if appeals are filed.

Echoes of past coups and insurrections

The charges brought against Yoon are among the most severe in South Korean legal history. If convicted of insurrection, he would become the third president found guilty of such a crime. The last two were military leaders who played pivotal roles in the 1979 coup, which led to years of authoritarian rule.

The prosecutors have hinted that they may draw parallels between Yoon's martial law declaration and the 1979 coup. Legal analyst Min said, “The precedent coup could be applied in the current case, as it also involved the coercive deployment of military forces.”

While a guilty verdict could technically result in the death penalty, the likelihood of execution remains low. South Korea has upheld an informal moratorium on capital punishment since 1997. Still, a life sentence remains a very real possibility if the court finds him guilty beyond reasonable doubt.

Political and public reactions

The beginning of the criminal trial of Yoon Suk Yeol has polarized the country. His supporters argue that Yoon was acting to stabilize the nation in a moment of crisis, while critics view his actions as a grave threat to democracy. Across South Korea, protestors and supporters alike have gathered in cities to make their voices heard.

Some political analysts believe that the outcome of this case will have ripple effects far beyond Yoon’s personal fate. “This trial is not just about one man—it’s about setting boundaries on presidential authority,” said law professor Kim Ji-hoon of Korea University. “Future presidents will be watching this very closely.”

In conservative strongholds, Yoon still has backers who claim the impeachment was rushed and politically motivated. Others believe that his actions crossed a red line and that he must be held accountable to uphold democratic integrity.

International observers watch closely

Yoon’s trial has also drawn attention from international human rights organizations and legal observers. South Korea’s democratic institutions are often held up as a model in Asia, and how the judiciary handles this high-profile case will be a major test of the rule of law.

Human Rights Watch issued a statement Monday urging the court to “uphold due process and guarantee a fair and transparent trial for all parties involved.” Meanwhile, foreign diplomats based in Seoul are monitoring developments closely, with some attending the trial’s opening session.

The weight of precedent

The criminal trial of Yoon Suk Yeol may be one of the most defining legal events in the nation's recent history. It tests not only the credibility of South Korea’s democratic institutions but also the very foundation of civilian oversight over the military. The evidence presented in court will have to show that Yoon intended to subvert constitutional order using force—a heavy burden of proof, but one the prosecution seems prepared to meet.

As the proceedings continue, the nation waits, watching its former president sit in the defendant's seat—a striking reversal for a man who once held the country’s highest office. Regardless of the outcome, the trial is poised to reshape public perceptions of executive power and democratic resilience in South Korea for years to come.