South Korea’s embattled former president, Yoon Suk Yeol, has been convicted of abuse of power, falsification of official documents, and obstruction of justice over his failed attempt to impose martial law in 2024. The court sentenced him to five years in prison.

In addition to this conviction, Yoon is still facing three other trials on charges that include insurrection and violations of campaign laws.

The ruling comes more than a year after his brief martial law decree plunged South Korea into political instability and deepened divisions across the country.

Below is an outline of the major charges brought against him.

Obstruction of justice

On Friday, the court found Yoon guilty of obstructing justice by evading arrest, abusing his authority by declaring martial law without first convening a cabinet meeting, and falsifying state documents.

Prosecutors said he misused state institutions for personal ends, concealing misconduct and weakening constitutional safeguards.

In January last year, authorities needed around 3,000 police officers and two separate attempts to detain Yoon for questioning over the insurrection case. During the standoff, Yoon reportedly deployed a large contingent of security personnel to form a human barricade inside his residence to prevent his arrest—an act a special prosecutor described as unprecedented.

Yoon argued that the Corruption Investigation Office lacked the legal authority to investigate insurrection charges against him.

According to Mason Richey, an associate professor at Hankuk University of Foreign Studies in Seoul, the disorder surrounding both arrest attempts highlighted “clear lawlessness” involving Yoon, his conservative party, and domestic security agencies. He said the obstruction of justice trial was intended to ensure accountability for those actions.

Insurrection

Under South Korea’s constitution, sitting presidents are immune from criminal prosecution except in cases involving insurrection or treason.

Yoon was formally charged with insurrection on 26 January 2025. At that point, parliament had already voted to impeach him, though he had not yet been officially removed from office.

Prosecutors allege that Yoon violated the constitution by declaring martial law despite the absence of war or any national emergency. They accuse him of deploying troops and police to block access to the National Assembly to prevent lawmakers from overturning his decree, and of ordering the arrests of the Assembly speaker and the leaders of major political parties.

Yoon previously claimed the declaration was necessary to defend the country against “anti-state” forces sympathetic to North Korea. However, prosecutors argue it was driven primarily by his personal political difficulties.

The prosecution has sought the death penalty, describing Yoon as showing no remorse. South Korea, however, has not carried out an execution since December 1997.

Former president Chun Doo-hwan, who ruled as a military dictator in the 1980s, was once sentenced to death for leading an insurrection, though the sentence was later reduced to life imprisonment. His successor, Roh Tae-woo, also received a lengthy prison term. Both were eventually pardoned.

Prosecutors now argue that Yoon’s 2024 martial law attempt inflicted even greater damage on the nation’s dignity than the 1979 military coup led by Chun and Roh.

Law professor Lim Ji-bong noted that Yoon’s courtroom behavior—smirking and laughing during witness testimony—worked against him. Lim believes the judge is more likely to impose a life sentence rather than the death penalty to avoid turning Yoon into a political martyr, warning that a death sentence could further inflame tensions among his supporters.

Christopher Jumin Lee, a US-based lawyer and Korea specialist, said he expects Yoon to be pardoned eventually, as Chun and Roh were. “That’s customary in Korean politics,” he said, adding that any sentence would mainly serve as a symbolic recognition of the gravity of the crimes.

Aiding an enemy state

Prosecutors have also accused Yoon of attempting to provoke North Korea into attacking the South as a pretext for declaring martial law.

This allegation is based on evidence recovered from the phone of former military intelligence chief Yeo In-hyung, including messages suggesting deliberate provocation, as well as a memo advocating the creation of instability or exploitation of emerging opportunities.

The trial on this charge, which began on Monday, will examine claims that Yoon ordered drone incursions into North Korea to escalate tensions between the two countries. Yeo and former defence minister Kim Yong-hyun have also been indicted on the same charge.

Other charges

Yoon is additionally accused of perjury over testimony he gave during the trial of former prime minister Han Duck-soo, who was charged with aiding the insurrection.

Prosecutors say Yoon falsely claimed he had long planned to convene a cabinet meeting before declaring martial law. Investigators contend no such plan existed and that the meeting was only held after Han urged him to do so.

Beyond the martial law-related cases, Yoon faces several other indictments. He is one of 33 individuals charged with obstructing an investigation into the death of a young marine officer in 2023 and allegedly helping the main suspect.

He has also been charged with interfering in the 2022 presidential election and making false statements during his campaign.