From martial law to democratic renewal in South Korea

On the night of Dec. 3, 2024, South Korean President Yoon Suk Yeol declared emergency martial law, triggering confusion and fear in Seoul that harkened back to the country’s arguably most intense period of authoritarian rule that persisted through the 1970s and early 1980s. South Korea, an economically advanced, fully consolidated democracy, had not experienced martial law in over 44 years, disrupting decades of democratic governance. Under the pretext of eliminating alleged “pro-North Korean anti-state forces” and to overcome political gridlock, Yoon deployed military forces to the National Assembly to enforce martial law as lawmakers rushed to parliament to vote to overturn Yoon’s edict. Following the vote and under pressure from ordinary citizens, Yoon lifted martial law by dawn.

Facing a constitutional crisis, the present members of the opposition-controlled National Assembly unanimously voted to end martial law. Lawmakers, with support from several members of President Yoon’s own party, voted to impeach Yoon on Dec. 14, immediately suspending his powers. These actions, along with those of South Korean courts, served as initial tripwires to protect South Korean rule of law and democracy.

During the nearly six months between Yoon’s impeachment in December 2024 to President Lee Jae-myung’s election in 2025, South Koreans navigated through unfamiliar constitutional terrain. The National Assembly launched a parliamentary probe and introduced legislation (later passed into law) amending guidelines for future martial law declarations and proposing legislature protections and other safeguards for civilian personnel. After reviewing evidence that included testimony in public hearings from participants and witnesses, the Constitutional Court unanimously upheld the impeachment charge against Yoon on April 4, 2025. Yoon’s impeachment triggered a constitutionally mandated 60-day timetable for special elections to be held following impeachment. On June 3, 2025, exactly 60 days after the court ruling, South Koreans elected Lee Jae-myung of the center-left Democratic Party. 

In the aftermath of this episode, South Korea’s democracy remains resilient, but it is by no means perfect and continues to be tested. Political polarization has intensified over the past decade. In a two-party, winner-take-all system, the main conservative and progressive parties often treat their rivals as existential threats to be eliminated. As political scientists Yul Sohn and Won-Taek Kang argue, “Electoral campaigns have shifted focus from promoting policies and showcasing competency to fueling animosity between rival parties.”

Although the crisis exposed gaps in constitutional processes, international observers praised South Korea for its handling of the martial law crisis and its aftermath. The Constitutional Court and the prosecutor’s office moved swiftly and followed constitutional procedures to conduct evidentiary hearings, issue criminal indictments, and uphold the National Assembly’s impeachment. The resilience of democratic institutions, including constitutional checks on the executive branch, pressure from civil society, and the military’s restraint helped South Koreans navigate a relatively soft landing following a crisis that could have potentially ended with a much worse outcome. A November 2025 Gallup Poll indicates that confidence in domestic institutions, including the military, the election process, and the judicial system, has rebounded since martial law. 

South Korea’s handling of its most significant political crisis and threat to democracy in decades, and the political transition that followed, offers insights for other democracies grappling with democratic backsliding and political change under conditions of intense polarization. We examine three positive aspects of South Korea’s democratic resilience during and after an extraordinary political transition. 

First, the judicial responses to the crisis underscored the importance of judicial independence and a robust system of checks and balances. Following Yoon’s declaration of martial law and his subsequent impeachment by the National Assembly, the Constitutional Court reviewed the impeachment through a formal judicial process rather than a partisan one, demonstrating how courts can serve as critical institutions for safeguarding democracy.

This was followed by a separate, criminal trial, in which judges at the Seoul Central District Court convicted Yoon of leading an insurrection, although appellate proceedings have since been suspended. Together, these proceedings illustrate how judicial institutions can operate independently, transparently, and responsively during periods of political turmoil

The Constitutional Court’s proceedings were particularly notable in this regard. Between January and February of 2025, the court convened 11 official hearings as part of former President Yoon’s impeachment trial. During over half of the hearings, 16 witnesses, including senior Cabinet officials, military commanders, and domestic security officials, testified on topics ranging from Cabinet proceedings to Yoon’s orders the night of the martial law crisis. The court also reviewed extensive evidence, such as presidential orders, internal communications, and testimony concerning troop deployments and efforts to restrict the activities of the National Assembly

Ultimately, the court found that no imminent national emergency or armed threat warranted invoking martial law and that Yoon had abused his presidential emergency powers.

Five of the eight justices appointed to the Constitutional Court at the time of the court’s ruling on Yoon’s impeachment presumably leaned moderate to conservative in their political orientation, including one justice appointed under Acting President Choi Sang-mok. Although the justices faced political pressure from both ends of the political spectrum, the court’s unanimous 8-0 ruling signaled that it acted as a constitutional body, not a partisan one, thereby reaffirming judicial independence as a key bulwark to prevent democratic backsliding.

The Constitutional Court’s demonstration of timely action, public accountability, extensive use of witnesses and documentation, and resistance to political pressure should stand as examples for judicial bodies globally. The South Korean court system took decisive, methodical action in helping the country navigate the crisis’s aftermath by demonstrating urgency and resolve in a step-by-step process between the impeachment vote in December 2024 and the announcement that the impeachment was upheld in April 2025. The witness testimonies, notes, memos, and other evidence compiled during the proceedings informed the court’s assessment of whether a factual and constitutional basis existed for Yoon’s declaration of a national emergency. When the justices delivered the unanimous ruling, they made a concerted effort to clearly explain their legal reasoning to uphold the impeachment of Yoon in a televised address. The court served as the final constitutional check on executive power. However, the crisis highlighted the need to strengthen institutional safeguards, such as protections for the legislature and laws that enable the military and/or civil servants to refuse illegal orders, to prevent similar political crises in the future.

Second, President Lee Jae-myung made national unity an early priority of his presidency, and thus far, has sought to govern from the political center as a pragmatist rather than an idealogue. This was not always the case for Lee, a career politician who had embraced progressive causes and become a polarizing figure facing at least six indictments for alleged offenses, including bribery, corruption, and misuse of public funds. 

However, rather than exacting retribution against his political opponents (a common occurrence in Korean politics), Lee, at least rhetorically, has sought to unite rather than divide the country. As Lee stated in his inaugural address, “It is time to build bridges of coexistence, reconciliation, and solidarity over the hatred and confrontation that have divided us … Regardless of whom you supported in this election, I will become a ‘president for all,’ embracing and serving every citizen, in keeping with the meaning of the word ‘daetongryeong’ (‘president’ in Korean) that calls for broad national unity.”

Lee’s pragmatism has manifested itself in his approach to filling Cabinet appointments with experienced figures spanning the private sector, civil society, bureaucracy, and media. In a show of bipartisan unity, Lee retained Minister of Agriculture, Food and Rural Affairs Song Mi-ryung from the previous Yoon administration. He also initially nominated former conservative party lawmaker and economist Lee Hye-hoon as minister of planning and budget, though the nomination was eventually withdrawn amid mounting personal controversies.

On foreign policy, rather than relying primarily on historical precedents, the Lee administration has made economic prosperity and national security the key drivers of its policy decisions. This pragmatic approach is evident in the Blue House’s efforts to manage military risks with Pyongyang, modernize the alliance with Washington, and strengthen regional cooperation with Tokyo. Lee named Wi Sung-lac, a respected career diplomat turned lawmaker, as his national security advisor. Wi is a strong proponent of the U.S.-South Korea alliance, an experienced hand in negotiations with North Korea, and a supporter of closer ties with neighboring countries, such as Japan. In addition, the appointments of Cho Hyun, another career diplomat and former UN ambassador, as minister of foreign affairs, and Ahn Gyu-back, a five-term lawmaker, as the first civilian minister of national defense since democratization, further corroborate this foreign policy evolution.

Third, since taking office, Lee has focused on governing and moving the country forward rather than dwelling too deeply on martial law and the wrongdoings of the opposition. Although investigations and prosecutions of former leaders—including Yoon and former Prime Minister Han Duck-soo—have resulted in criticism from the conservative opposition for the Lee government, they have not dominated the political agenda or paralyzed governance. 

The economy remains a top concern among the South Korean public as national growth reached just 1% in 2025. Since taking office, Lee has prioritized reviving domestic national growth by pursuing expansionary fiscal policy and proposed structural reforms across key sectors, ranging from finance to education, while managing an export-driven economy amid headwinds. 

Central to his economic strategy is artificial intelligence. The 2026 national budget proposes more than tripling investment in AI to bolster national industries, defense, and public services, with the goal of becoming a top three global AI power. In response to higher energy prices due to ongoing conflict in the Middle East, the Lee government has devised measures to mitigate the high costs of energy while pursuing longer-term energy transition policies. 

President Lee has generally received high marks, with approval ratings oscillating between high 50s and mid-60s one year into office. Even as South Korea navigates external challenges, ranging from energy disruptions to U.S. tariff pressure, Lee has emphasized the need for a collective response to weather each crisis.

On June 3, 2026, 18 months after Yoon’s martial law declaration and nearly one year after President Lee’s inauguration, South Koreans held local elections. With the ruling Democratic Party winning 12 of 16 metropolitan mayoral and gubernatorial races, the election was widely viewed as a referendum on President Lee’s leadership and another test for democratic resilience post-martial law. While the results strengthened Lee’s political position and created opportunities for greater alignment between national and local policy, the opposition’s victory in the high-profile Seoul mayoral race points to a potential conservative revival. Support from younger voters in their 20s and 30s combined with outrage over Election Day ballot shortages, including in several conservative-leaning districts in Seoul, suggests greater political contestation in the next electoral cycle.

South Korea’s handling of the December 2024 martial law crisis and its aftermath demonstrates that democratic preservation is possible even under conditions of extreme polarization and institutional strain. The swift restoration of constitutional order, combined with the Lee government’s leadership and emphasis on national unity, judicial independence, and pragmatic governance, helped prevent a descent into democratic backsliding despite the country’s well-documented democratic flaws.

Although political divisions may have deepened since the crisis, the Lee government has exercised relative political restraint—particularly given the ruling party’s wide majority in the legislature. In that vein, South Korea’s recent experience offers valuable lessons for other democracies navigating democratic backsliding, contentious elections, leadership change, and the challenge of rebuilding trust after crisis.