South Korea ousts President Yoon Suk Yeol over martial law decree: What's next?

In a dramatic climax to South Korea’s deepening political crisis, the Constitutional Court on Friday officially removed President Yoon Suk Yeol from office, setting the stage for a by-election within 60 days that could reshape the nation's political future.

The unanimous verdict by all eight justices comes months after Yoon declared martial law and dispatched troops to the National Assembly—moves the court ruled as blatant constitutional violations. Yoon still faces rebellion charges that could carry the death penalty or life imprisonment.

But the man at the center of South Korea’s most severe democratic test since the 1980s isn’t stepping away quietly.

A president deposed, but not defeated
Yoon, a combative former prosecutor who narrowly won the presidency in 2022, declared martial law on December 3, alleging that the liberal opposition was "anti-state" and using its majority to block his agenda. Troops stormed the legislature and election offices, with orders later revealed to prohibit "all political activities."

Lawmakers, however, defied the occupation, re-entered the chamber, and unanimously repealed the martial law declaration within hours. Days later, on December 14, the National Assembly impeached Yoon.

Testimony from top military and police officials described a deliberate—but botched—attempt to shut down the legislature. The court dismissed Yoon’s claim that it was a symbolic warning, concluding he had “mobilized military and police forces to obstruct the exercise of legislative authority.”

Yoon’s removal comes at a volatile moment. His conservative base remains fervent, staging riots in January after a court initially authorized his arrest. And though Yoon said in a statement that he "deeply regrets failing to live up to the public’s expectations," he hasn’t explicitly accepted the ruling.

Meeting with People Power Party leaders at the presidential residence he must now vacate, Yoon reportedly told them to "prepare well and win the upcoming election."

A race against time—and trust
The coming presidential vote will be held within 60 days, under the shadow of a nation split down ideological lines. The liberal-conservative divide, already stark, has been supercharged by Yoon’s failed power grab and his claims of election fraud.

“If people start refusing to accept any election outcome that is unfavorable to them, the other side will start doing the same,” said Kim Tae-hyung, a professor at Seoul’s Soongsil University. “If that cycle continues, trust in democracy will completely collapse.”

Experts warn of potential unrest at polling stations and call for heightened security. “There’s a high risk of disruption,” said Kim Su-min, a political analyst.

Yoon is expected to influence the election heavily, both in rhetoric and behind the scenes. Analysts say he will attempt to install a loyalist as the People Power Party’s nominee—possibly setting up a rematch with liberal Democratic Party leader Lee Jae-myung, who lost to Yoon in 2022 and is also facing criminal investigations.

Fallout beyond borders
The crisis has paralyzed Seoul’s foreign policy apparatus at a delicate time. With Donald Trump poised to reshape U.S. policy in Asia, South Korea may miss the window to assert its interests in upcoming diplomatic negotiations, warned Yonsei University’s Paik Wooyeal.

Meanwhile, prosecutors—freed from constitutional constraints now that Yoon is no longer president—are pursuing further charges. Several top officials, including the defense minister and police chief, have already been indicted for their roles in the martial law fiasco.

Yoon was released from custody in March but now awaits trial on rebellion charges. His legal jeopardy could intensify in the wake of the court’s decision.