How a failed martial law attempt landed South Korea’s ex-President in jail for five years | Explained

A man holds up a poster that reads 'Yoon Again' as he and other supporters of South Korea's ousted former leader Yoon Suk Yeol attend a protest in Seoul on December 6, 2025, three days after the one year anniversary of his short-lived martial law declaration. (Photo by Anthony WALLACE / AFP)

• Former president Yoon Suk Yeol sentenced to five years for martial law attempt
• Yoon convicted of obstructing arrest and falsifying documents
• He faces more trials, including an insurrection charge with potential death penalty.

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In an unprecedented moment for South Korean politics, a court on Friday sentenced former president Yoon Suk Yeol to five years in prison over his failed attempt to impose martial law late last year.

Yoon was convicted on charges linked to his actions after authorities moved to detain him in January. Investigators said he obstructed the execution of a lawful arrest warrant by barricading himself inside his residential compound and ordering the presidential security service to block police and prosecutors. His eventual arrest required a second operation involving more than 3,000 police officers, marking the first time a sitting president in South Korea was taken into custody.

The court also found Yoon guilty of falsifying official documents connected to his December 2024 declaration of martial law. He had claimed the move was necessary to restore democratic order, arguing that the country was under threat from the opposition-controlled legislature and what he described as “anti-state” forces. The court rejected that justification, ruling that the declaration lacked legal basis.

Yoon is currently being held at the Seoul Detention Center following the sentencing.

The five-year jail term does not conclude Yoon’s legal troubles. He is facing multiple additional trials, including a far more serious charge of masterminding an insurrection. Prosecutors have sought the death penalty in that case, arguing that his actions posed a direct threat to South Korea’s constitutional order. A verdict on the insurrection charge is expected in February.

The sentencing caps a dramatic fall for Yoon, whose presidency unravelled amid political deadlock, mass protests and accusations that he attempted to subvert democratic institutions. The case has sent shockwaves through South Korea, underscoring the judiciary’s willingness to hold even the highest office accountable under the law.