Prosecutors are investigating President Yoon Suk-yeol for possible treason after the prime minister and ruling party leader suggested Yoon is no longer involved in day-to-day governance of the country. 

South Korea now faces a constitutional crisis stemming from what experts describe as a legal loophole the People Power Party (PPP) is exploiting to compel Yoon to step down, but what this means and how long it is supposed to take is unclear. There appears to be no clear command authority to respond to a North Korean attack or other crisis.

“Put simply, this investigation is about a public official abusing their authority to incite a riot with the purpose of disrupting the constitutional order,” Park Se-hyun, the head prosecutor of the Special Investigation Headquarters for Martial Law, said at a press conference Sunday afternoon. 

While sitting ROK presidents are immune from most criminal charges, treason is not one of them. Constitutional provisions indicate that if Yoon is arrested or found guilty, the prime minister would temporarily assume an acting president role. Prosecutors have not yet announced a timeline for their investigation or if they plan to bring charges.

On Sunday, Prime Minister Han Duck-soo and the PPP leader Han Dong-hoon appeared to insinuate they are now leading the South Korean government and that Yoon is “excluded” from all future decision-making. The opposition denounced this scheme as “unconstitutional,” noting neither official has the authority to assume presidential powers without formal constitutional processes.

“We are essentially in a temporary constitutional collapse. Everything here is uncharted territory,” Jumin Lee, a former ROK Air Force officer who is now a trial attorney based in Los Angeles, told NK News. 

“Presidential powers cannot be suspended absent impeachment or incapacitation. They cannot be delegated to a private citizen at the president’s whim,” Lee explained. “And they certainly can’t be delegated indefinitely without the prospect of allowing the people to choose a new president.”

If Yoon Suk-yeol is found guilty of treason and the prime minister takes over as acting president, the latter will constitutionally inherit the authorities including the commander in chief role, according to Sang-sin Lee, director of the Center for the Study of Liberal Democracy at the Korea Institute for National Unification (KINU).

But he added that arrest or detention doesn’t equate to removal from office, meaning Yoon could potentially return as head of the executive if released.

Despite the morning’s announcement of Yoon’s informal exclusion from duties, he accepted the resignation of interior minister Lee Sang-min at around 4 p.m. KST on Sunday.

NORTH KOREA IS WATCHING

South Korea’s political turmoil has raised particular concerns about its military command structure, as the position of commander in chief (CIC) is the president’s sole prerogative. Both the presidential office and defense ministry declined NK News requests for clarification on the current chain of command. 

Despite the ongoing confusion, on paper Yoon is still the CIC. 

“Under the constitution and law, Yoon Suk-yeol is South Korea’s supreme military commander,” Lee of KINU said. 

Yang Uk, military analyst at the Asan Institute of Policy Studies, agreed, but said that Prime Minister Han would exercise “de facto military command” if Yoon is unable or unwilling to do so.  

Retired ROK Army Lt. Gen. Chun In-bum, a highly decorated military leader who served for almost four decades, told NK News that the prime minister should assume the CIC role in the current situation.

But in a contingency, the military reporting hierarchy may prove thorny, others pointed out. 

The situation is further complicated by recent military leadership upheaval. Multiple officials — including the acting defense minister, Joint Chiefs of Staff chairman, and special forces commander — pledged to disobey any further martial law orders from Yoon, indicating his diminishing authority as CIC.

“If I were the chairman of the Joint Chiefs of Staff, I would be confused about whom to report to” if North Korea sends drones across the border again, or penetrates the demilitarized zone, Jumin Lee told NK News. 

“There’s no civilian control over the military right now,” Lee warned. “Among civilians, only the president has legal military command authority … the prime minister’s office has no legal basis for military command.”

While lower-level escalations like missile tests or inter-Korean border activity are probably manageable despite the discord in Seoul, experts warn that scenarios similar to the Dec. 2022 drone incursion — which require top-level decision-making — could expose dangerous gaps in response capability. 

The ROK special forces and capital defense commanders are among several key military officials currently suspended from duty after the martial law fiasco. Kim Yong-hyun resigned from the defense minister post earlier this week and was arrested on treason charges Sunday. 

All of this increases the chances of miscommunication, delays and poor decisions in ways that could benefit Pyongyang in a crisis, experts said.

Edited by Arius Derr