Protesters gather near the National Assembly in Yeouido, wetern Seoul, on Saturday, calling for the impeachment of President Yoon Suk Yeol. Yonhap

President Yoon Suk Yeol's abrupt declaration of martial law has led to his impeachment, making him the third South Korean president suspended from office by the National Assembly.

His political fate now lies in the hands of the Constitutional Court.

The impeachment motion passed in a 204-85 vote, with three abstentions and eight invalid ballots on Saturday, narrowly clearing the 200-vote threshold in the 300-member parliament.

Notably, at least 12 lawmakers from Yoon’s 108-member ruling People Power Party broke ranks to back the motion.

Yoon's political gamble has ended in failure, with power now transferred to acting President and Prime Minister Han Duck-soo.

Critics argue that Yoon's push for a martial law decree was predominantly driven by personal factors: a deep disdain for the political process and a flagrant disregard for core democratic norms, including "institutional forbearance" -- the principle that demands leaders show restraint in exercising their legal and constitutional powers.

But Yoon's downfall has also exposed deeper systemic vulnerabilities within South Korea's political framework that allowed such a crisis to unfold, political analysts in Seoul contend.

At the core is the paralysis of party politics in the National Assembly under a divided government, where the opposition Democratic Party of Korea dominates the legislature and the ruling party controls the presidency.

Instead of resolving conflicts through political dialogue, both sides have leaned heavily on legal tactics: the main opposition group, the Democratic Party, has filed a record number of impeachment motions against Yoon administration officials, while the president has habitually wielded his veto against Assembly-passed bills.

Also, the inadequacy of institutional safeguards against presidential overreach, exemplified by Yoon's unilateral declaration of martial law, has revealed the vulnerabilities of Korea's president-centered system, where executive authority remains largely unchecked.

President Yoon Suk Yeol bows his head before delivering a public speech on Saturday, following his impeachment in a second vote at the National Assembly. Presidential official via Yonhap

Yoon's disdain for politics

Yoon, a political novice, was elected President in March 2022 just eight months after announcing his entry into politics in June 2021, marking a dramatic shift from his long career as a prosecutor. His lack of experience left him ill-equipped to navigate established political processes.

Yoon's martial law decree is, therefore, the result of deeply personal factors, including a disregard for political norms such as dialogue and consensus-building, as well as a lack of experience in managing the intricate dynamics of governance.

"The question ultimately comes down to whether this is an issue of institutional or structural flaws or a matter of individual misconduct. In my view, the impact of individual misconduct is significant,” Shin Jung-sub, a professor of political science at Soongsil University, said during a roundtable discussion entitled "Martial Law, Challenges to Constitutional Order and Korea's Democracy" on Dec. 10 held at the Yonsei University’s Seoul campus.

Analysts further highlighted the gravity of Article 1 of the Martial Law Command Order issued on Dec. 3, which explicitly prohibited "all political activities, including those of the National Assembly, local assemblies, political parties, political associations, gatherings and protests," underscoring the sweeping and authoritarian nature of the directive.

Lee Jae-mook, a professor of the Department of Political Science and Diplomacy at Hankuk University of Foreign Studies, pointed out that the clause was even absent from the Martial Law Command Order of Oct. 27, 1979.

That time was the last instance of emergency martial law, declared a day after the assassination of then-President Park Chung-hee, but the 1979 Martial Law Command Order stated, "All outdoor gatherings must receive prior authorization, and collective activities such as protests are prohibited."

"This highlights the extent of the president's apparent disdain for politics," Lee said.

Martial law troops attempting to force their way into South Korea's National Assembly chamber from the People Power Party leader's office are met with resistance from assembly staff wielding fire extinguishers in the early hours of Dec. 4. Yonhap

Ha Shang-eung, a political science professor at Sogang University, observed that Yoon's decision to declare martial law was rooted in his belief that the unicameral National Assembly was obstructive, making collaboration with the legislative branch seem untenable.

"This martial law was declared with the clear intent to suspend the functions of the legislature," Ha said.

Yoon has made a number of actions since becoming president that show his disdain for politics.

Yoon became the first Korean president in 11 years to skip the Assembly's plenary session for the annual budget address in November.

Yoon's first meeting with Democratic Party leader Lee Jae-myung took place this April, a record 720 days after Yoon's inauguration -- marking the longest delay for such talks since Korea became a democracy in 1988. By comparison, the previous record was set by then-President Kim Young-sam, who took 110 days to meet the opposition leader.

"The main opposition leader must be challenged through legitimate democratic competition, fostering political rivalry instead of relying on judicial risks and waiting for court rulings," Lee Jae-mook said, emphasizing the lack of political dialogue between Yoon and opposition parties.

"This absence of engagement allowed the situation of (legislative deadlock) to spiral out of control, ultimately triggering the use of an extreme measure (by Yoon) -- a card that institutional safeguards are designed to prevent and should never have been played."

Lee Geun-wook, a political science professor at Sogang University, pointed out that Yoon’s misguided belief that he could privatize the military played a key role in his abuse of presidential authority.

"He viewed the military as his own, rather than as the nation's or the people's, believing he could mobilize it whenever necessary. Essentially, he regarded the military as something he could privatize for his own use."

Park Chan-dae, floor leader of the main opposition Democratic Party of Korea, speaks at a National Assembly plenary session on Saturday, ahead of a vote on the impeachment motion against President Yoon Suk Yeol. (Yonhap)

Breakdown of party politics

Analysts highlighted a troubling lack of effective political processes at the Assembly amid grinding legislative deadlock, which they argue could be a factor that triggered Yoon to overstep his authority by declaring martial law.

Kim Jeong-hyun, a political science professor at Yonsei University, summarized Yoon's decision: "Faced with opposition from the rival party in a divided government, the president was unable to achieve his goals, ultimately resorting to extreme measures."

Ha Shang-eung underscored that "politics should be conducted during peacetime, while the law should be mobilized during times of crisis. However, the current state of Korean politics shows the opposite: the law is being wielded during peacetime, while political solutions are being sought in moments of crisis."

The overreliance on legal measures is evident.

Since taking office, Yoon has exercised his veto power 25 times, matching the combined total of all previous presidents, excluding Syngman Rhee, who issued 45 vetoes during his tenure from 1948 to 1960.

On the other hand, opposition parties have launched an unprecedented number of impeachment motions, filing 22 between Yoon’s inauguration and his martial law decree on Dec. 3. This is a record-breaking figure, compared to six under Moon Jae-in, one under Park Geun-hye excluding her own impeachment, and three during Roh Moo-hyun’s presidency excluding his own impeachment.

"Both sides are entrenched in their belief that they are justified, resulting in a standoff where each relies solely on legal mechanisms. One side argues they can file as many impeachment motions as they want within the law, while the other insists they can exercise vetoes just as freely," Ha said. "When legal tools are wielded this way during peacetime, compromise becomes impossible."

Shin Jung-sub argued that such deadlock could be resolved through political dialogue and negotiation, providing a healthy political culture exists, and the divided government operates effectively with a sound balance of power and checks.

"However, in the absence of such a political culture, both sides resort to exploiting every institutional tool available, escalating the confrontation to extremes," Shin said. "Ultimately, it could be argued that a leader unable to exercise sound judgment under such circumstances made the worst possible decision."

President Yoon Suk Yeol greets merchants and visitors at Gongju Sanseong Market in South Chungcheong Province on Dec. 2. Presidential Office via Yonhap.

Flaw of presidential system

Against that backdrop, Shin pointed out that Yoon's martial law declaration also "has revealed the greatest flaw of the presidential system from an institutional perspective."

Analysts highlighted the structural weaknesses of South Korea's presidential system, noting how its overwhelming concentration of power in the presidency undermines the effectiveness of party politics and institutional balance.

"The opposition parties focus their battles against the presidential office, bypassing the ruling party at the National Assembly, while the ruling party avoids engaging with the opposition and instead seeks approval from the president," Lee explained. "In a system where everything revolves around the president, political parties are rendered ineffective, further deepening the dysfunction."

Under the winner-takes-all presidential system and a majoritarian electoral framework that entrenches a two-party dynamic, political parties often prioritize power over ideology, values, or policy agendas.

This structure grants the president near-absolute authority while providing rival parties little incentive to pursue consensus-driven governance, fueling legislative deadlock and deepening political polarization, according to the analysts.

Lee also pointed out that "We have come to recognize just how limited the mechanisms are to effectively check the authority and powers of the president."

"Unless the president steps down voluntarily or is impeached, there are few ways to restrain presidential overreach," Lee said.

Lee also highlighted that Yoon-sparked political turmoil also illustrates another critical flaw of the presidential system, stating, "One of the biggest flaws of the presidential system is that it allows unchecked outsiders, who may lack proper vetting, to rise to power and wield it freely."

Yoon has faced criticism over first lady Kim Keon Hee’s acceptance of a Dior bag, drawing parallels to former President Park Geun-hye’s impeachment, which stemmed from allegations of improper influence by her confidant, Choi Soon-sil.

"To prevent similar situations from happening again, institutional reforms are urgently needed. Whether through constitutional amendments or legal and structural changes within the current framework, some form of systemic overhaul seems inevitable," Lee said.

Protesters chant slogans during a rally near the National Assembly in Yeouido, Seoul, on Saturday, demanding the impeachment of President Yoon Suk Yeol. Yonhap

Kim Jeong-hyun highlighted that the "silver lining" of Yoon's martial law decree lies in its ability to provoke thought about the critical role of politics and the dangers it poses when misused, potentially depriving people of their fundamental rights.

"This incident serves as an opportunity for the public to give serious thought to the underlying flaws in our political system," Kim said, emphasizing that it is time for Korea to confront these issues head-on by questioning and discussing necessary reforms to its electoral system and broader political framework with the public.

Kim stressed the urgent need for reforms to empower voters to push lawmakers toward negotiation and cooperation within the frequently recurring divided governments of Korea’s political dynamics, in order to overcome the structural flaws that perpetuate a cycle of deadlock and polarization.

"We need to engage in deeper discussions on how to establish institutional mechanisms that encourage politicians to pursue negotiation and collaboration, as well as how to provide electoral incentives for such behavior from the voters’ perspective."