South Korea's president arrest: what happens next?

Impeached leader Yoon Suk Yeol made history this week as the first sitting South Korean president to be arrested, ending a weeks-long standoff. But analysts say the country's political crisis is far from over.

Yoon said he's cooperating to avert "bloodshed" but invoked his right to remain silent and his lawyers are using "every legal tactic" in the book, analysts say, against the insurrection probe into his ill-fated declaration of martial law.

He also faces a separate Constitutional Court case that could finalize his impeachment and removal from office.

Here is the state of play:

- President behind bars? -

Yoon, who remains South Korea's sitting head of state, is being held at the Seoul Detention Center.

Yoon's lawyers have said the investigation lacks legitimacy and challenged the legality of the arrest, and Yoon himself is refusing to speak -- even as investigators address him as "Mr President".

"It appears that every legal tactic is being employed by Yoon's team to prolong the situation," Lee Jong-soo, a law professor at Yonsei University, told AFP.

Because of the complexity of the investigation, and the number of different authorities involved, "it doesn't appear that this can be done quickly," Lee said.

Yoon is accused of "acts of insurrection... one of the few crimes for which even the president can be prosecuted," lawyer Chu Eun-hye said.

The trial could take months, Chu said, but the separate impeachment hearing could move more quickly.

- And the impeachment? -

Eight justices at the country's Constitutional Court are now deliberating whether to uphold Yoon's impeachment and remove him from office. Six must rule in favour.

They will review whether Yoon's martial law declaration was unconstitutional and illegal.

Their ruling -- which could come as early as February or as late as June -- is the only official way to remove Yoon from office.

The court is ruling on "a constitutional process" whereas the probe is a criminal investigation, Vladimir Tikhonov, Korean Studies professor at the University of Oslo, told AFP.

"These two processes proceed on different planes," he added.

Only the impeachment trial can judge whether "the president can no longer be trusted with the position," professor Lee at Yonsei Law School told AFP.

"Even if Yoon is acquitted in a future criminal trial, he can still be removed from office based on the impeachment ruling," he said.

- What about elections? -

If Yoon is removed from office, fresh elections will have to be held within 60 days -- which would likely be won by the opposition, politics expert Park Sang-byung told AFP.

But fresh polls are unlikely to resolve South Korea's deep-rooted political tensions and could, in fact, lead "to more intense conflicts," Park warned.

"Even if a new presidential election occurs, I'm afraid the already divided political landscape is expected to worsen."

Yoon's party will likely seek to undermine and even impeach a new opposition president, Park said, "making bipartisan agreements increasingly difficult".

- And Yoon's party? -

Yoon is the second successive conservative president to be impeached, after Park Geun-hye who was removed from office in 2017 over a corruption scandal.

After that political disaster, Yoon's People Power Party re-branded and were, after five years in opposition, able to return to power thanks to their widely understood role as South Korea's traditional conservative bloc.

But under Yoon, "there are concerns that it has been co-opted by far-right elements since his declaration of martial law and his impeachment," Lee Jae-mook, a political science professor at the Hankuk University of Foreign Studies, told AFP.

"If this trend continues, it risks alienating centrist voters and losing touch with public sentiment. While this may yield short-term advantages, it could have detrimental effects in the long run."

- Economic woes? -

Yoon's arrest has also caused economic rumblings in Asia's fourth-largest economy.

Consumer sentiment fell to its lowest since the Covid-19 pandemic, the South Korean won plunged against the dollar and the country's unemployment rate spiked to the highest since 2021.

"It is still difficult to determine the impact of political uncertainties, as the effects will depend on how long the conflicts continue," Rhee Chang-yong, Bank of Korea governor told reporters on Wednesday.

"The fourth quarter of last year was affected by the martial law situation. Growth rates beyond the first quarter of this year remain highly uncertain," he added.

But if the Constitutional Court acts fast and "political instability is resolved early, the negative economic impact is likely to be minimal," said Park Sang-in, Seoul National University Economics professor.

© Agence France-Presse