A South Korean court has sentenced a former Prime Minister to 23 years in prison for his involvement in the ill-fated imposition of martial law by the then President Yoon Suk Yeol.

Ex-Prime Minister Han Duck-soo became the first Yoon administration official convicted of rebellion charges in relation to the martial law imposition in December 2024.

Han, who was appointed by Yoon, served as one of the three caretaker leaders during the martial law crisis that led to Yoon’s impeachment and eventually his removal from office.

Former South Korean Prime Minister, Han Duck-soo.

Rebellion is one of the gravest criminal charges in South Korea, with the independent counsel recently demanding the death penalty for Yoon, who was charged with masterminding a rebellion. The Seoul Central District Court is to rule on Yoon’s rebellion charges on February 19, 2025.

In a televised verdict, the Seoul court determined Yoon’s martial law decree amounted to a rebellion, viewing his dispatch of troops and police officers to the National Assembly and election offices as “a riot” or “a self-coup” that was meant to undermine the constitutional order and was serious enough to disrupt stability in South Korea.

The court sentenced Han for playing a key role in the rebellion by trying to give procedural legitimacy to the martial law decree by getting it passed through a Cabinet Council meeting.

The court also convicted Han of falsifying the martial law proclamation and destroying it and lying under oath.

The court said that Han neglected his responsibilities as Prime Minister, the No. 2 post in South Korea, to protect the constitution, choosing instead to take part in Yoon’s rebellion in the belief that it might succeed.

Judge Lee Jin-gwan said, “Because of the defendant’s action, the Republic of Korea could have returned to a dark past when the basic rights of the people and the liberal democratic order were trampled upon, becoming trapped in the quagmire of dictatorships for an extended period.”

Han’s lengthy sentence came as a surprise as the independent counsel earlier requested a 15-year prison term. He is a career bureaucrat who served as Prime Minister twice during his 40 years of public service, first under liberal President Roh Moo-hyun from 2007 to 2008 and later under Yoon.

Han became acting President after Yoon was impeached by the opposition-controlled National Assembly later in December 2024.

However, he was also quickly impeached following wrangling with opposition lawmakers over his refusal to fill vacant seats at the Constitutional Court, which was deliberating whether to formally throw Yoon out of office.

Observers said at the time that restoring a full court bench could increase prospects for Yoon’s ouster.

The Constitutional Court later reinstated Han as acting President but after the court formally dismissed Yoon as President in early April, Han resigned to run for the presidency in last June’s snap election.

He eventually withdrew from the race after failing to win the main conservative party’s nomination. Lee Jae Myung, a former leader of the main liberal opposition Democratic Party, won the election.

Yoon, who has already been in jail for months, faces eight criminal trials including his rebellion case over the martial law decree and other allegations.

Last Friday, Yoon received a five-year prison term at the Seoul court for defying attempts to detain him, fabricating the martial law proclamation and denying some Cabinet members their rights to deliberate on his martial law decree.

Verdict Expected To Set Stage For Other Rulings

The verdict is expected to set the stage for upcoming rulings involving Yoon and his other associates, who also face rebellion charges.

Han, 76, who could appeal the ruling, has steadfastly maintained that he had told Yoon that he opposed his martial law plan. He has denied most of the other charges.

Besides Han, Yoon’s defense, Safety and Justice Ministers, spy and Police Chiefs as well as some of his top military commanders have been indicted on rebellion and other charges related to the martial law imposition.