SEOUL, South Korea (AP) — The South Korean Constitutional Court's decision to formally unseat President Yoon Suk Yeol is another test for the country's democracy after the conservative-liberal divide deepened over his imposition of martial law and subsequent impeachment.

The court’s ruling Friday triggers a by-election for a new president.

Yoon still faces criminal charges of rebellion, but he's unlikely to fade into the background. He is likely to thrust himself onto the political agenda, rallying his hard-core supporters and influencing the choice of the next leader of his party, which has made intensive efforts to regroup around calls for his reinstatement.

Here’s what you need to know about the court decision.

Why did the court remove Yoon from office?

All eight of the Constitutional Court’s current justices upheld the impeachment motion and dismissed Yoon as president.

The constitutional crisis began on Dec. 3 when Yoon declared martial law and dispatched troops to the National Assembly. Lawmakers defied hundreds of soldiers and police officers to enter the legislative chamber and unanimously voted to lift martial law within hours.

On Dec. 14, the liberal opposition-controlled assembly impeached Yoon and suspended his presidential powers, accusing him of violating the constitution by declaring martial law, deploying troops to the legislature and election offices, and attempting to arrest opponents.

The constitution limits the exercise of martial law to times of war or comparable national emergencies. Yoon argued his decree was necessary to bring attention to what he called an “anti-state” main opposition party that abused its legislative majority to obstruct his agenda.

Even under martial law, the president doesn’t have the authority to shut down the legislature. Shortly after Yoon’s martial law declaration, the military’s martial law command issued a proclamation prohibiting “all political activities,” including those of the National Assembly.

Yoon has insisted that he never intended to disable the legislature, saying he sent troops there to maintain order, not to disrupt the vote. He also denied accusations that he sought arrests of rival politicians.

Yoon’s claims were contradicted by testimony from several senior military and police officers, who described a deliberate but poorly executed attempt to seize the legislature. In removing Yoon from office, the Constitutional Court rejected his argument that martial law was merely a temporary warning or an appeal to the public, stating he clearly violated the constitution and laws by “mobilizing military and police forces to obstruct the exercise of legislative authority.”

South Korea has 60 days to choose a new president

South Korea must now hold a presidential election within 60 days — potentially one of the most tense votes since the country’s transition from dictatorship in the late 1980s. The country’s electorate is deeply divided along ideological lines and Yoon’s legal saga has exacerbated polarization.

Yoon's conservative supporters rioted at the Seoul Western District Court that authorized his arrest in January. Yoon's lawyers and the ruling party have openly questioned the credibility of that court and law enforcement institutions, and he has continued to express contempt for his liberal rivals, endorsing baseless conspiracy theories about election fraud to justify his ill-fated authoritarian push.

Experts say Yoon’s actions are fueling severe political division, making compromise unlikely, and threaten to undermine the election by inspiring voter distrust in the results. There’s a high risk of disruption during the voting process, making it crucial to elevate security at polling and counting stations, said Kim Su-min, a politics analyst and former Gumi city council member.

“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.”

Yoon may not go quietly

Yoon, never one to back down from a fight, may refuse to be ignored. In the coming weeks, he may rally supporters in the streets while trying to tighten his grip on the People Power Party, whose leadership is stacked with his loyalists and which has seen its popularity rebound with calls for his reinstatement.

In a statement issued through his lawyers, Yoon said he deeply regrets failing to live up to the public’s expectations, but didn’t specifically say whether he accepts the court’s ruling. Later, in a meeting with the conservative People Power Party leaders at the presidential residence he must vacate, Yoon urged them to prepare well and win the upcoming election, a party spokesperson told local media.

Facing a separate criminal trial on rebellion charges — punishable by death or life in prison — Yoon would strongly prefer a conservative president who could pardon him if convicted and will likely push to ensure his party’s primaries are won by a candidate he supports, Kim Su-min said. This would turn the upcoming election into a near-rematch between Yoon and liberal Democratic Party leader Lee Jae-myung, who narrowly lost to Yoon in 2022 and has his own legal troubles.

Whoever it is, South Korea’s next leader will face critical challenges. The turmoil caused by Yoon’s power grab and impeachment has disrupted high-level diplomacy and hurt the economy, as well as weakening Seoul’s ability to respond to tariffs and other shifts in U.S. policy under President Donald Trump.

Trump’s diplomatic lineups for South Korea and neighboring countries are expected to be completed before a new government is inaugurated in Seoul. This could pose a significant foreign policy challenge to South Korea, which won’t have a chance to explain its positions to the Trump administration ahead of formal negotiations, said Paik Wooyeal, a professor at Seoul’s Yonsei University.

Yoon still faces criminal charges

Yoon was released from prison in March after the Seoul Central District Court cancelled his arrest and allowed him to stand trial without being detained.

But as a former president, Yoon has lost the presidential privilege that protected him from most criminal prosecution except on grave charges like rebellion. Prosecutors can now pursue other criminal charges related to Yoon’s martial law declaration and seek to detain him.

Legal experts said the Constitutional Court’s dismissal of Yoon could increase the chance he will be convicted of rebellion charges at the Seoul Central District Court.

Yoon’s defense minister, police chief and other senior military commanders have also been arrested and indicted over their roles in the martial law imposition.

FILE - People watch a TV screen showing South Korean President Yoon Suk Yeol's televised briefing at a bus terminal in Seoul, South Korea, Dec. 3, 2024. (AP Photo/Ahn Young-joon, File)

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FILE - People try to enter the National Assembly in Seoul, South Korea, on Dec. 3, 2024. (AP Photo/Lee Jin-man, File)

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FILE - South Korean lawmakers attend during a plenary session of the impeachment vote of President Yoon Suk Yeol at the National Assembly in Seoul, on Dec. 14, 2024. (Woohae Cho/Pool Photo via AP, File)

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FILE - South Korean National Assembly Speaker Woo Won-shik, center, announces the result of voting for president impeachment during a plenary session of the impeachment vote of President Yoon Suk Yeol at the National Assembly in Seoul, on Dec. 14, 2024. (Woohae Cho/Pool Photo via AP, File)

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FILE - Participants celebrate after hearing the news that South Korea's parliament voted to impeach President Yoon Suk Yeol outside the National Assembly in Seoul, South Korea, on Dec. 14, 2024. (AP Photo/Lee Jin-man, File)

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FILE - Impeached South Korean President Yoon Suk Yeol arrives at the Corruption Investigation Office for High-ranking Officials in Gwacheon, South Korea, on Jan. 15, 2025. (Korea Pool via AP, File)

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FILE - Police officers stand guard as supporters of impeached South Korean President Yoon Suk Yeol try to enter the Seoul Western District Court in Seoul, South Korea, Saturday, Jan. 18, 2025. (AP Photo/Ahn Young-joon, File)

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FILE - Impeached South Korean President Yoon Suk Yeol attends his impeachment trial at the Constitutional Court in Seoul, South Korea, Tuesday, Jan. 21, 2025. (Kim Hong-Ji/Pool Photo via AP, File)

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FILE - Impeached South Korean President Yoon Suk Yeol waves to his supporters as he comes out of a detention center in Uiwang, South Korea, on March 8, 2025. (Hong Hyo-shik/Newsis via AP, File)

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