Yoon's issuance of martial law in December 2024 constituted a deliberate attempt to "paralyze" the legislature for an extended period of time, a Seoul court ruled.
This happened when Yoon, described as a strong conservative, mobilized military and police forces and had politicians in the liberal-dominated parliament arrested.
The sudden imposition of martial law plunged South Korea into a political crisis that has been called the country's worst in decades. The court points out that Yoon has not expressed any remorse for his actions.
Protect from “communism”
When Yoon Suk-Yeol declared martial law, he said it would protect the country from "communist forces." He was ousted a few months later after South Korea's Constitutional Court ruled in an impeachment proceeding that the proclamation did not meet the legal requirements for a national emergency.
Prosecutors have previously sought the death penalty for Yoon. However, the death penalty has not been carried out in South Korea since 1997, and the country is considered to have effectively abolished it.
Previous verdict
Yoon Suk-Yeol was sentenced to five years in prison in January in the first of a series of pending sentences. The charge was "attempted obstruction of justice." The country's former first lady, Kim Keon-Hee, Yoon's wife, was also recently sentenced to 20 months in prison for corruption.
Former Prime Minister Han Duck-Soo was also recently sentenced to 23 years in prison for "neglecting his duty" when martial law was declared.
Thursday's verdict also covers a number of former military and police officers involved in the imposition of martial law, including a former defense minister who was sentenced to 30 years in prison for playing a central role in its planning and execution.
Yoon Suk-Yeol is expected to appeal Thursday's verdict.
