Introduction
There has been widespread recognition among constitutional scholars that the Constitutional Courts of South Korea (the KCC) and Taiwan (the TCC) are products of democratisation, contributing to the consolidation of constitutional democracy.Footnote 1 While the two Courts generally play an active role in safeguarding constitutionalism, their extensive activism has often obscured inquiries into their efforts to grapple with institutions of national security inherited from the authoritarian era and retained after the transition to democracy.Footnote 2 Scholars have recognised the KCC’s comparatively deferential stance towards the South Korean National Security Act, a special criminal law enacted in 1948 that regulates anti-state organisations and, inter alia, addresses pro-North Korean advocacy.Footnote 3 In contrast to the scholarly attention paid to the KCC, there has been little exploration of the TCC’s approach to this topic, other than a few commentaries discussing the TCC’s case law on transitional justice.Footnote 4 Are the KCC’s and TCC’s responses to national security law the same? How can we rationalise the forces driving their patterns of behaviour?
In this article, I compare how the KCC and TCC address national security laws enacted prior to democratisation. In the decades before the democratisation of South Korea and Taiwan, their authoritarian regimes relied on the state intelligence agencies, military courts and secret police to establish and enforce a kind of permanent state of emergency or martial law in the name of national security.Footnote 5 Structural remnants of these institutions remain embedded in the contemporary legal order,Footnote 6 thereby providing a basis for the Courts’ more rigorous approach to national security law. At the same time, South Korea’s and Taiwan’s geopolitical complexities can complicate internal security conditions,Footnote 7 generating a critical need for national security governance; this governance demands a higher degree of judicial deference due to its inherently political and technical nature.Footnote 8 As a result, the KCC and TCC face challenges regarding the bounds of state power in addressing national security issues.
By employing mixed-methods research, I argue that while the KCC and TCC display certain similarities, they are also different from one another. Both Courts have reconfigured national security law in light of their respective understandings of the relationship between security and constitutional rights protection.Footnote 9 However, the KCC has consistently foregrounded security threats rooted in South Korea’s particular security conditions and, through the application of general constitutional principles, has adopted a high degree of judicial deference in national security cases.Footnote 10 As a result, the KCC’s jurisprudence has arguably created a grey zone in which authoritarian practices inherited from pre-transition national security institutions may continue to interact with − and be sustained by − contemporary security governance. In contrast, the TCC appears less enthusiastic in examining the specific nature of threats and their contemporary implications for national security. Instead, the TCC has largely rejected the security-first narratives inherited from Taiwan’s authoritarian past, favouring the application of general constitutional principles over deference to asserted security imperatives.
The stories of the South Korean and Taiwanese Constitutional Courts offer important lessons for research on national security law, not only in East Asia but around the world. Although many studies have focused on national security law in hybrid or authoritarian states,Footnote 11 far fewer have explored its ramifications for new democracies. The findings presented here show that by adjudicating national security cases, constitutional courts play an important role in facilitating a constitutional negotiation between liberty and security in new democracies. This constitutional negotiation rests on considerations of justice, liberty, and the rule of law, as many studies of constitutionalism have argued. Importantly, it also rests on particular understandings of security and threats, as well as of the normative weight accorded to them within each constitutional order.Footnote 12 In other words, constitutional courts have imprinted, distilled, and institutionalised their respective societies’ thinking on security into their constitutional practices. This thinking on security, in turn, interacts with prevailing understandings of the rule of law and constitutionalism in each society.Footnote 13
Before proceeding, it is worth noting that my aim in the present study is to explore the role of the KCC and TCC in reframing national security law in the democratic era. It is not my primary goal to examine how courts in general should evaluate security issues through a normative lens on ‘security vs liberty’.Footnote 14 Moreover, this article is not about transitional justice and how states should address past large-scale violations of human rights in post-totalitarian or authoritarian contexts.Footnote 15 There are indeed issues of transitional justice that remain unresolved, especially in the context of national security law. However, I leave questions of rectifying past wrongs for future studies in transitional justice. Instead, my goal in this article is to focus on how national security law in the post-transition context has been understood by the judiciary. I will examine the two Courts’ patterns of behaviour associated with national security law, including the conceptual tools they have adopted to adjudicate security matters in their respective domestic and geopolitical circumstances.
The remainder of the article is structured as follows. In the next section, I analyse the literature on national security law, focussing on the role of courts in adjudicating this area of law. Thereafter, I summarise the methods employed and then present case studies of South Korea and Taiwan. I will then present a comparative analysis of the causes and consequences of the two Courts’ responses to their respective national security laws. I offer concluding remarks in the final section.
National security law and courts in new democracies
Constitutional review in new democracies has been a topic of considerable interest in comparative constitutional law.Footnote 16 After the fall of the Berlin Wall, many newly emerging democracies established constitutional courts to adjudicate political disputes and to review potentially unconstitutional statutes and regulations.Footnote 17 These courts, more than many other institutions, have had to grapple directly with pre-transition regulations that persist through legal frameworks and precedents, as well as the institutional preferences of administrative staff.Footnote 18 When doing so, they often face a dilemma: on the one hand, these regulations likely exhibit features of their authoritarian origin, which, by persisting after democratisation, may undermine the ability of democratic institutions to safeguard the rule of law and other fundamental rights.Footnote 19 On the other hand, the objectives of these regulations may align with contemporary public expectations or policy needs, justifying the courts’ more deferential approach to the political branches of government.Footnote 20 How constitutional courts can navigate these competing pressures thus becomes a crucial yet underexplored question.
National security law is one of the most significant examples of authoritarian-era structures that may persist in a post-transition democratic state. As comparative legal scholars have shown, authoritarian and hybrid governments often use national security law, alongside other legal tools, to control perceived threats to the domestic social and political order.Footnote 21 The quest for regime legitimacy drives these governments to establish broad zones of ‘national security exceptionalism’, insulating governmental decision-making from public scrutiny and legal control.Footnote 22 The scholarly attention devoted to these practices reflects the importance of national security law as a tool for hybrid or authoritarian regimes.
What remains underexplored is how, after long periods of authoritarian rule, national security law may become entrenched, even after authoritarianism has given way to democracy.Footnote 23 For instance, while many new democracies undertake neutralisation reforms to ensure civilian control over the military, such reforms do not always succeed; military leaders in many democratised countries continue to exercise significant influence over governmental decision-making, raising concerns about democratic accountability.Footnote 24 At the same time, as the operation of national security institutions requires a significant level of confidentiality and hierarchy, there are also good reasons for other branches of government and external stakeholders, such as the media, to reduce their scrutiny in the context of national security.Footnote 25
Scholarly discourse about judicial politics provides a useful starting point for considering courts’ responses to national security law. On the one hand, constitutional courts may have a strong incentive to earn institutional legitimacy in the eyes of society.Footnote 26 They may thus hone their abilities to gauge the political desires of various segments of society. If there is a widespread and pronounced desire for a non-repressive way of life, constitutional courts may have a strong incentive to invalidate unconstitutional national security statutes if they exhibit clear legacies of the authoritarian past. As such, constitutional courts can be more immune to, and defiant of, these authoritarian tendencies than other parts of government. On the other hand, national security law usually involves high political stakes, secrecy, and complex technical knowledge.Footnote 27 In response, courts in new democracies may be reluctant to review matters related to national security law.Footnote 28 The rationale for this reluctance may be that overturning laws involving high political stakes could provoke unwanted political turmoil, undermining political stability, which is a prerequisite for the courts’ institutional credibility.Footnote 29 Moreover, courts may consider themselves to lack the necessary knowledge to override policy decisions made by the political branches of government, which typically have access to a broad range of skilled experts and professional knowledge.Footnote 30 As a result, there are also good reasons for courts to take a more deferential approach in national security cases.
While these accounts of judicial politics offer a useful starting point, they mistakenly generalise the nature of past national security law as a monolithic body of law that is either eliminated or preserved entirely. Such generalisations ignore that the rigidity or transformability of national security law is also a matter of context that requires further scrutiny.Footnote 31 This is because national security law builds upon a country’s constitutional thinking regarding its physical boundary, sense of security, and the government’s role in securing public safety; all these aspects may involve divergent understandings of security and liberty in different jurisdictions, including how these jurisdictions react differently to historical narratives of security and how they persist in the democratic present.Footnote 32 This article will thus not focus on the behaviour of courts in response to a generalised understanding of national security law across countries; instead, it will take a closer look at how courts review concrete cases through the lens of their national security and liberal values. I summarise my research methods below.
Research methods
This article examines the responses of the South Korean and Taiwanese Constitutional Courts to the authoritarian legacies of national security law. I have relied on interdisciplinary methods to analyse the available data on the national security decisions of these Courts and critically reflect on how they develop new jurisprudence through the lens of security. This approach diverges from prior research, which does not distinguish between different categories of national security law that may persist or transform over time.Footnote 33 Yet, recognising differing categories of national security law is particularly significant, as courts may subject pre-democratisation laws to divergent levels of scrutiny. In contrast to prior research, my method aims to examine the Courts’ roles in cases involving historically rooted security concerns as well as their relevance to the present.
I employed a keyword-search method to analyse national security decisions in the South Korean and Taiwanese contexts from the time of their democratisation (in the late 1980s) through 31 December 2024. The keywords ‘national security’, ‘security’, and ‘area security’Footnote 34 in Korean and traditional Chinese languages were used to identify decisions in which the Courts determined questions of constitutionality of relevant laws. My decision to take this approach is based on the rationale that courts may be less politically strategic in this context than in that of ‘ancillary powers’ – such as the dissolution of political parties, the resolution of intra-governmental disputes, and impeachment cases; studying judicial behaviour in the context of ‘ancillary powers’ would thus generate a pattern of judicial behaviour that is not directly comparable to that observed in constitutional review.Footnote 35 Accordingly, constitutional review provides a useful framework for ensuring a consistent basis for comparing the behaviour of constitutional courts across jurisdictions.
In addition, I aim to analyse the Courts’ roles in facilitating the systemic change in national security law within the post-transition context, rather than their roles in remedying violations of constitutional rights in specific cases, which may involve a greater range of concrete factual considerations. On this premise, I analyse the KCC’s decisions on the constitutionality of laws in response to two types of petitions: the first one is made by lower courts regarding the constitutionality of statutes, and the second consists of constitutional complaints filed by individuals according to article 68(1) and (2) of the Korean Constitutional Court Act, excluding petitions without a judicial declaration of the (un)constitutionality of laws.Footnote 36 In contrast to the KCC’s concrete review, the TCC conducts only abstract review of the constitutionality of statutes, not including constitutional complaints, prior to the enactment of the Taiwanese Constitutional Court Procedures Act on 4 January 2022. The KCC and the TCC thus offer a reasonably useful body of case law for analysis.
I have limited my analysis to cases in which the Courts rendered substantive decisions, excluding those dismissed on procedural grounds. I acknowledge that excluding such cases may not fully capture their national security jurisprudence, especially given that courts often exercise a degree of discretion in distinguishing between procedural and substantive issues. Nevertheless, focusing on substantive decisions enables a more meaningful and critical examination of the Courts’ engagement with the factual and legal dimensions of particular cases.
An examination of the historical background reveals two categories of disputes linked to national security law originally associated with the former authoritarian regimes. The first category (‘Category I’) includes disputes over laws explicitly titled ‘National Security Acts’; this labelling is the clearest indication of their national security character. In the second category (‘Category II’) are disputes involving laws originally enacted by the respective authoritarian regimes (or immediately after democratisation by the incumbent governments to entrench power if no power transition occurred). In this category, the Courts have either acknowledged that the issues involve significant national security interests or rejected the existence of a reasonable or substantial connection to national security.Footnote 37 Compared to Category I, Category II is, by nature, much broader. It encompasses a wide array of factual contexts, regulatory frameworks, and legal issues, which in turn elicit diverse responses from the Courts. Accordingly, this categorisation serves only to provide a general overview of the national security cases decided by the KCC and TCC. It does not imply that the Courts adopt a consistent approach within any particular category.
Based on the collected decisions, I conducted a general comparison of the behaviour of constitutional courts. I relied on official statistics in the case of South Korea and manual coding in the case of Taiwan to analyse declarations of unconstitutionality, that is, decisions in which the Courts determined that at least one relevant law was unconstitutional, non-conforming to the constitution, or conditionally unconstitutional. The purpose of this comparison is not to draw any statistical inferences from this necessarily limited dataset; instead, it is to provide prima facie evidence of the presence or absence of judicial deference in the context of national security.
After quantitatively comparing how each Court handled the relevant cases, I conducted a contextual analysis of the KCC’s and TCC’s attitudes with respect to national security law and policy. In particular, I examined how the two Courts addressed governmental measures imposed under authoritarian rule. This descriptive analysis was then compared with the two Courts’ three representative lines of jurisprudence for contemporary national security cases: (1) conscientious objection; (2) other matters related to military service; and (3) freedom of expression. Both the KCC and TCC have issued landmark decisions in each of these areas, making them especially suitable for comparative analysis. To be clear, this comparative analysis is not intended to offer an exhaustive or finely detailed examination of every judgment listed in the appendices. Instead, it seeks to offer a cross-jurisdictional comparison that highlights the similarities and differences between the two Courts. While this methodological choice inevitably sacrifices a degree of comprehensiveness, it enables readers to gain meaningful comparative insights into how the KCC and the TCC converge or diverge in their approaches, based on a reasonably accurate and representative assessment of their jurisprudence.
The Constitutional Court of South Korea and its national security decisions
Background
The Korean Peninsula gained independence from Japan in 1945, following thirty-five years of colonial rule, and was divided into northern and southern political blocs. In 1948, the former transformed into the Democratic People’s Republic of Korea (North Korea), embracing communist ideology, and the latter became the Republic of Korea (South Korea), which is generally characterised as a pro-Western country. Since its establishment, South Korea has competed with North Korea for sole representation of the Korean Peninsula, and their contentious relationship has had profound implications for both governments’ security policies.Footnote 38
The first government (1948-1960) established by Rhee Syngman was envisioned to be a democratic one; yet it was fragile and unstable and was soon succeeded by the Second Republic, a short-lived parliamentary government, in 1960, right before a coup d’état was carried out by Park Chung-hee in 1961.Footnote 39 During the Third Republic (1961-1972) and the Fourth Republic (1972-1981), Park established a security-based and anti-communist regime, suppressing political dissidents and progressive activists through emergency decrees, including those perceived to be associated with North Korea.Footnote 40 In particular, the Constitution of the Fourth Republic, known as the Yushin Constitution (1972-1979), granted Park unfettered presidential powers.Footnote 41 Following Park’s assassination in 1979 and the subsequent dissolution of the Fourth Republic, the authoritarian government of Chun Doo-hwan, during the Fifth Republic (1981-1987), continued Park’s security-based policies, maintaining social and political stability through surveillance, security agencies, and military force.Footnote 42
It was not until 1987 that South Korea entered a new democratic era, the Sixth Republic, and, to mark the shift from authoritarianism to democracy, adopted a new constitution.Footnote 43 The 1987 Constitution embraces liberal constitutionalism; it accommodates citizens’ demands for democracy, enhances political competition, and strengthens the rule of law.Footnote 44 Democratic transformations also enabled new constitutional thinking regarding the decades-old and highly intricate inter-Korean conflict after the 1953 armistice agreement.Footnote 45 Specifically, article 3 of the Constitution explicitly stipulates that the Republic of Korea’s territory includes the entirety of the Korean Peninsula, which serves as a constitutional basis for denying the legitimacy of the North Korean government.Footnote 46 Article 4 of the Constitution emphasises the government’s responsibility to seek peaceful unification based on free and democratic order.Footnote 47 It signals an important achievement of South Korea’s democratic movements, which successfully replaced the previous authoritarian governments and their anti-communist platforms.Footnote 48
Articles 3 and 4 point to a ‘dual structure’ of the relationship between the two Koreas: article 4 sets out an ideological goal of peaceful unification, while article 3 constitutes a legal declaration of territorial sovereignty.Footnote 49 In addition to the seemingly incompatible commitments enshrined in articles 3 and 4, article 5 stipulates that the government should maintain international peace and shall renounce all aggressive wars;Footnote 50 Article 69 requires presidents to devote themselves to the ‘peaceful unification of the homeland,’ though how such an outcome would be achieved is left unstated in the text.Footnote 51
Throughout South Korea’s democratic development, a hugely difficult and persistent policy question has been whether the government should, by interpreting the abovementioned articles, treat North Korea as an existential security threat or as an annoying neighbour with a shared history and cultural traits. This task is particularly intricate considering that the two Koreas are technically at war because they have not replaced the 1953 armistice agreement with a peace agreement.Footnote 52 Since 1987, South Korea’s presidents, in accordance with their distinct ideological and policy inclinations, have crafted and implemented divergent foreign policies in fulfilment of these constitutional mandates. These policies are often linked with domestic political concerns about national security, and these concerns, in the context of South Korean democracy, can evolve rapidly and be intensely polarising.Footnote 53
An overview of the KCC’s national security decisions
The KCC is a product of the 1987 Constitution.Footnote 54 It comprises nine justices appointed by the president with the approval of the National Assembly, including three selected by the National Assembly and three selected by the Chief Justice of the Supreme Court.Footnote 55 The justices, who serve renewable six-year terms, are responsible for determining the constitutionality of statutes, adjudicating impeachment cases involving high-ranking politicians, deciding on the dissolution of political parties and the resolution of disputes between state organs, as well as adjudicating constitutional complaints.Footnote 56
The KCC has a critical role in South Korea’s post-transition democracy. It is frequently involved in high-profile disputes, making influential decisions about a wide range of public issues.Footnote 57 National security law is no exception. As illustrated in Table 1, between 1988 and 2024, the KCC issued sixty-eight substantive decisions declaring a law to be unconstitutional, non-conforming to the Constitution, conditionally unconstitutional, conditionally constitutional, or constitutional. Of these, eighteen were directly concerned with the South Korean National Security Act (SKNSA; Category I) and fifty involved laws originally enacted under the authoritarian regime to pursue national security interests (Category II).
The KCC’s National Security Decisions
Table 1 Long description
Number of decisions are listed by Category I, Category II, and Total. In the row, Declarations of unconstitutionality, Category I has 2, Category II has 15, and the Total is 17. In the row, Total, Category I has 18, Category II has 50, and the Total is 68. In the row, Rate, Category I is 11.11 percent and Category II is 30.00 percent, while the Total column is blank.
Source: Author
Among the eighteen decisions in Category I, the KCC found the relevant provisions unconstitutional in two decisions. The unconstitutionality rate in this category is 11.11%, which is lower than the average of 24.90%.Footnote 58 Among the fifty Category-II decisions, the KCC found the relevant provisions unconstitutional in fifteen decisions. The unconstitutionality rate in this category is 30.00%, slightly higher than the average. These figures indicate the KCC’s deferential approach to constitutional review when considering Category I decisions, which involve higher national-security stakes. All decisions are listed in Appendix I (see Tables AI1 and AI2).
The KCC’s reasoning in national security decisions
Article 37(2) of the Korean Constitution stipulates that ‘the freedoms and rights of citizens may be restricted by Act only when necessary for national security, the maintenance of law and order or for public welfare.’Footnote 59 In accordance with this provision, the KCC has routinely reviewed whether and how a specific national security regulation conforms to the principles of clarity and proportionality in pursuing national security.
To be sure, in 2010Hun-Ba132 et al (2013), the KCC determined three emergency decrees promulgated by Park Chung-hee from 1974 to 1975 under the Yushin Constitution (Decrees Nos 1, 2, and 9) to be unconstitutional.Footnote 60 While all three decrees had lost legal force by the end of the Fourth Republic, the KCC emphasised that they should be subject to judicial review, primarily because they were immune from judicial scrutiny under the Yushin Constitution, posing a serious challenge to the preservation of South Korea’s current constitutional order.Footnote 61 On this basis, the KCC held that, among other things, citizens’ expression of their political views is not a ‘national security threat’, but a political activity that constitutes an essential element protected by liberal democracy.Footnote 62 By prohibiting the exercise of freedom of expression in the name of national security and emergency, Decrees Nos 1 and 2 clearly went beyond the permissible limits of the Constitution.Footnote 63 The Court also found that Decree No 9 – which stipulated a complete ban on any claim regarding the revision or repeal of the Yushin Constitution – had violated the freedom of expression and freedom of assembly, in addition to other political rights and constitutional principles.Footnote 64 In its decision, the Court stated that the military confrontation between the two Koreas had been an ‘ever-present crisis under the reality of hostile confrontation between South and North’ since the armistice of the Korean War.Footnote 65 Therefore, the ‘abstract and subjective perception of the situation of the war’ does not amount to an exigent situation which may justify the president’s declaration of an emergency.Footnote 66
In contrast to the KCC’s rigorous posture in emergency cases related to the authoritarian period, it has taken a more deferential approach when reviewing three categories of national security disputes, though sometimes with exceptions: (1) conscientious objection; (2) other matters related to military service; and (3) freedom of expression.
Conscientious objection. Article 19 guarantees the freedom of conscience. Nevertheless, military service has been compulsory for young men and has been considered one of the most important obligations in South Korea.Footnote 67 The Military Service Act, originally enacted in 1949, authorised the government to prosecute citizens who, without ‘justifiable grounds’, refused to perform compulsory military duties (article 88(1)).Footnote 68 Between 1959 and 2019, more than 20,000 individuals were sentenced to prison terms for violating this legal provision.Footnote 69 Despite the troubling human rights record associated with the application of the Military Service Act, the KCC has repeatedly upheld its constitutionality, citing the compelling need to maintain a sufficiently large military to prepare for any potential wars arising from the ongoing conflict between the two Koreas.Footnote 70
In 2002Hun-Ka1 (2004), for instance, the KCC encountered article 88(1) of the Military Service Act. In this case, the plaintiff, a draftee who was required to serve in the military, challenged article 88(1) on the ground that it violated his freedom of conscience. In a seven-to-two decision, the KCC held that freedom of conscience is a relative freedom; it does not necessarily enjoy a preferred status over Korean nationals’ obligation to perform military service.Footnote 71 It is thus necessary for the legislature to balance the ‘public interest’ and the ‘individual interest’ in a particular context.Footnote 72 Article 88(1), the KCC held, sought to protect national security, a critical state interest and a prerequisite for the existence of the state and the protection of citizens’ lives and safety.Footnote 73 Considering Korea’s ‘current security conditions, the need for equal protection in the enforcement of conscription, and several restrictive elements for introducing alternative services',Footnote 74 the legislature enjoys broad discretionary power to determine Korea’s national security policy, including matters related to military service.Footnote 75 In this regard, the KCC held that article 88(1) was justifiable as an exercise of the legislature’s reasonable judgment.Footnote 76
After this decision, the KCC continued to rule on article 88 in subsequent cases.Footnote 77 Indeed, in 2011Hun-Ba379 (2018), the majority struck down article 5(1) of the Military Service Act, which stipulates the types of military service.Footnote 78 In this six-to-three decision, the Court criticised the National Assembly for its failure to offer alternative service programmes to the plaintiffs. In considering proportionality, the Court reasoned that while the legislative purpose was legitimate, article 5(1) imposed undue harm on the freedom of conscience of conscientious objectors prosecuted under the Act. Moreover, offering alternative service programmes could fulfil the general public interest in national security by increasing the capacity of modern military institutions to tackle new security threats.Footnote 79 However, on the same day, the Court also ruled that article 88(1) was not unconstitutional because it is not only an appropriate means but also the least intrusive one to protect national security.Footnote 80 Moreover, the benefits it achieves, including the protection of national security and core constitutional values, outweigh the costs.Footnote 81
The National Assembly revised the Military Service Act on 27 December 2019 to offer several alternative service programmes based on the Court’s instructions.Footnote 82 Nevertheless, the amendment faced criticism and a constitutional challenge in 2024, based on the purported failure of the National Assembly to include community service as a form of alternative service. The Court, in a five-to-four decision, responded by endorsing the arrangement that included a service of thirty-six months in correctional facilities, citing the need to maintain a sufficiently strong system of military service for security purposes.Footnote 83
Military service: prohibition of same-sex sexual contact. The KCC’s deferential stance is also evident in decisions about ‘disgraceful or indecent’ sexual behaviour under the Military Criminal Act. Article 92(5) of the old Military Criminal Act, originally enacted in 1962, criminalised consensual same-sex intercourse or other types of sexual contact, irrespective of temporal and spatial considerations, and without regard to the civilian status of the other party.Footnote 84 Article 92(5) and related provisions were challenged before the Court several times, but the KCC repeatedly relied on the principle of proportionality to hold that article 92(5) did not violate the petitioners’ rights to privacy, equality, and sexual self-determination.Footnote 85
In 2012Hun-Ba258 (2016), for instance, the KCC stated that the legislative purpose of article 92 was to promote ‘a sound communal life in the military’ and to establish ‘military discipline.’Footnote 86 Prohibiting indecent acts is an appropriate means of achieving this purpose. Moreover, criminal punishment is the least intrusive means because administrative regulations cannot effectively regulate indecent acts in light of the country’s security conditions. Finally, the extent of right restrictions does not outweigh the interest to be achieved, namely national security.Footnote 87
In 2017Hun-Ka16 (2023), the KCC encountered article 92(6), which criminalised a person who engaged in anal intercourse or other indecent acts with someone affiliated with the military.Footnote 88 The KCC held that it was consistent with the Constitution. The reasoning given by the Court was similar to that in 2012Hun-Ba258: criminal punishment was deemed to be an appropriate means for establishing and maintaining military discipline.Footnote 89 It is also the least intrusive means compared to other administrative measures, given the difficulty of maintaining military discipline in a highly hierarchical institutional structure.Footnote 90 Moreover, the disadvantages suffered by those subject to criminal punishment do not outweigh the public interest in national security. For this reason, criminal punishment met the constitutional requirement of proportionality.
Freedom of expression. The SKNSA was adopted by the South Korean government in 1948 amidst increasingly escalating confrontations with North Korea right after Korean independence.Footnote 91 The 1948 version of article 7 of the SKNSA criminalised a wide range of expressive acts that could be interpreted as supporting anti-state activities. Thus, it became a criminal offence for people (1) ‘to praise, encourage, disseminate or cooperate’ with an anti-state entity; (2) ‘to create or spread false information which may disturb national order’; and (3) ‘to create, import, duplicate, possess, transport, disseminate, sell, or acquire documents, arts or other publications’ with the express intent of supporting anti-state policies.Footnote 92 North Korea has long been considered an ‘anti-state organization’Footnote 93 under the ambiguously worded article 7; even those remotely suspected of engaging in jongbuk activities (ie, pro-North Korea activities) would be subject to article 7.Footnote 94
After South Korea democratised, the SKNSA – and article 7 in particular – garnered a great deal of attention among domestic politicians.Footnote 95 Eventually, its provisions were brought before the KCC. In a landmark decision, 89Hun-Ka113 (1990),Footnote 96 the Court recognised concerns that article 7 could permit arbitrary enforcement by the authorities, thus substantially infringing upon the essence of fundamental rights.Footnote 97 Nevertheless, the Court relied on the doctrine of ‘conditional constitutionality’ to rule that article 7 could be upheld as constitutional only if it were applied in circumstances where individuals knowingly endangered South Korea’s existence, security, as well as the fundamental order of liberal democracy.Footnote 98 Following the decision, the National Assembly amended article 7 as instructed by the Court.
According to the Court, the rationale for adopting this method of ‘conditional constitutionality’ lies in the prolonged military confrontation between the two Koreas.Footnote 99 Based on this understanding, invalidating article 7, or the SKNSA as a whole, would cause greater harm to South Korea’s security than retaining the Act.Footnote 100
After 89Hun-Ka113, the Court issued a further seven decisions in which it declared the constitutionality of article 7.Footnote 101 For instance, in 95Hun-Ka2 (1996), the KCC stressed that the subjective requirement associated with the jeopardisation of ‘the existence of the state and the fundamental order of liberal democracy’ set out in the revised article 7 was then more clearly defined, and that any remaining ambiguities could likely be addressed through reasonable judicial interpretation.Footnote 102 Moreover, in 89Hun-Ma240 (1997), the Court stressed that while both Koreas joined the United Nations in 1991, and the Agreement on Reconciliation, Non-Aggression, and Exchanges and Cooperation between South and North Korea was signed in 1991, these circumstances cannot be regarded as eliminating the necessity of the SKNSA.Footnote 103 Accordingly, it cannot be said that a different judgment from those previously adopted is required.Footnote 104 Similarly, in 2012Hun-Ba95 et al (2015), the KCC reviewed several clauses of article 7 and held that they did not violate freedom of expression, among other constitutional freedoms, in part because they satisfied the tests of proportionality.Footnote 105
The Constitutional Court of Taiwan and its national security decisions
Background
In 1945, the Kuomintang (KMT), then the governing party of the Republic of China (ROC), assumed control of Taiwan following the end of Japan’s colonial rule (1895-1945).Footnote 106 Two years later, the KMT government promulgated a constitution that was initially intended to govern the ROC, with Taiwan treated as a province alongside the provinces of mainland China. In 1949, the KMT lost the Chinese Civil War to the Chinese Communist Party (CCP) and retreated to Taiwan. The CCP assumed control of mainland China and established the People’s Republic of China (PRC).Footnote 107 The KMT and CCP governments have each since claimed to be the sole legitimate government of China, encompassing mainland China and Taiwan.
The profound antagonism between mainland China and Taiwan is the backdrop against which the authoritarian KMT governed the island. It justified its authoritarian rule by invoking a national security narrative in which the ROC had to protect itself from the constant threat posed by the PRC.Footnote 108 Starting in 1948, the KMT implemented a series of security-oriented measures that were clearly inconsistent with the democratic-sounding principles in the ROC Constitution. In fact, just prior to its defeat in the Chinese Civil War, the KMT government rejected the principles of separation of powers and suspended national elections by implementing the Temporary Provisions under the Period of National Mobilisation (the Temporary Provisions); these remained in effect from 1948 to 1991.Footnote 109 In 1949, the government imposed martial law in Taiwan, curtailing the rule of law for almost forty years (martial law was not lifted until 1987).Footnote 110
For the KMT, the ROC Constitution became a primary symbol of political legitimacy, supporting the KMT’s claim to sovereignty over the entirety of China.Footnote 111 The KMT consistently insisted that the ROC Constitution should remain in its original form to preserve an ‘important symbol of political legitimacy’Footnote 112 and to enable its enforcement in mainland China after the KMT’s victory over the CCP. Despite the KMT’s vigorous assertion of its political legitimacy to domestic and international audiences, the KMT government led by Chiang Ching-kuo, the son of Chiang Kai-shek, faced an increasingly hostile international environment. In 1971, the General Assembly of the United Nations adopted Resolution No 2758, recognising the PRC, not the ROC, as the sole legitimate representative of China. Taiwanese citizens’ discontent with the KMT’s repressive rule also intensified, with reform-minded grassroots movements gaining momentum. The chief outcome of this domestic agitation was the formation of the Democratic Progressive Party in 1986, one year before martial law was lifted in 1987. The government’s decision to abolish the Temporary Provisions in 1991 ushered in elections for Taiwan’s two national legislative bodies at the time: the National Assembly (1991) and the Legislative Yuan (1992). These critical steps effectively renewed the democratic legitimacy of these institutions.Footnote 113
With Taiwan’s political liberation and ‘the changing complexity of the geopolitical environment engulfing the Taiwan Strait’,Footnote 114 it became clear that there was a significant need for a new constitutional system designed specifically for Taiwan.Footnote 115 Nevertheless, given the PRC’s persistent assertions of sovereignty over Taiwan, any manifestations of independence or self-governance by Taiwan – such as the 1996 presidential election – could provoke military action from the PRC.Footnote 116 Moreover, for many politicians and citizens, the belief in the ‘unamendability of the ROC Constitution’ had become entrenched.Footnote 117 In this ambiguous geopolitical and domestic landscape, Taiwan did not adopt a new constitution. Instead, it retained the main body of the Constitution and made revisions in the form of additional provisions, with the latest amendment in 2005.Footnote 118 The purpose of these additional provisions, according to the preamble, was ‘to meet the needs of the nation prior to national unification’.Footnote 119 The ambiguous phrase ‘prior to national unification’ reflected how the drafters strategically navigated political elites’ different interpretations of national territory – especially during the uncertain period of democratisation.Footnote 120
An overview of the TCC’s national security decisions
The TCC (originally known as the Council of Grand Justices) is a product of the 1947 ROC Constitution. During Taiwan’s periods of authoritarianism, the TCC was a rubber stamp for the KMT government, providing legal justification for the KMT government’s monopoly over public authority in Taiwan. The TCC transformed into an active judiciary reinforcing the rule of law and human rights in Taiwan’s newly democratised landscape. In the past several decades, the TCC has come to be widely considered an independent, authoritative interpreter of the Constitution.Footnote 121
The TCC comprises fifteen justices, nominated by the president and approved by the Legislative Yuan. Justices are drawn from diverse backgrounds, including judges, prosecutors, lawyers, university professors, academic researchers, and other distinguished professions.Footnote 122 The design of the Court is intended to foster a dynamic environment where justices with varied backgrounds bring diverse perspectives and enrich the process of constitutional adjudication.
From the end of martial law on 15 July 1987 through 2024, the TCC has carefully reviewed various matters associated with Taiwan’s national security law. As illustrated in Table 2, the TCC issued a total of fourteen substantive decisions, including three decisions concerning the National Security Act for the Period of National Mobilisation for Suppression of the Communist Rebellion (the formal National Security Act) and the amended National Security Act (Category I), and eleven decisions in which the relevant laws were originally enacted during or immediately after the period of authoritarian rule in the name of national security (Category II).
The TCC’s National Security Decisions
Table 2 Long description
National security decisions are counted by category, with columns for Category I, Category II, and Total. In the row, Declarations of unconstitutionality, Category I has 1 decision and Category II has 9, for a total of 10. In the row, Total, Category I has 3 decisions and Category II has 11, for an overall total of 14. In the row, Rate, Category I is 33.33 percent and Category II is 81.82 percent, while the Total column is blank.
Source: Author
As Table 2 shows, the TCC has been active in addressing national security law in a general sense. In total, the Court held laws unconstitutional in ten decisions, resulting in an unconstitutionality rate of 71.43% – substantially higher than its overall average of 47.05%.Footnote 123 Indeed, among the three decisions in Category I, the TCC found the relevant provisions unconstitutional in only one case (33.33%). For Category II, the TCC’s unconstitutionality rate is 81.82%, which is also substantially higher than the Court’s average. All decisions are listed in Appendix II (see Tables AII2 and AII3).
The TCC’s reasoning in national security decisions
In reviewing national security disputes, the TCC regularly invokes the principles of clarity, proportionality, and Gesetzesvorbehalt (loosely translated as the principle of statutory reservation, see below).Footnote 124 The Court’s adoption of these principles is primarily based on article 23 of the ROC Constitution, which stipulates that ‘all the freedoms and rights enumerated … shall not be restricted by law except such as may be necessary to prevent infringement upon the freedoms of other persons, to avert an imminent crisis, to maintain social order or to advance public welfare.’ Unlike the South Korean Constitution (in article 37(2)), the ROC Constitution does not explicitly identify national security as a legitimate justification for restricting individual freedoms or rights; the TCC has recognised national security as a legitimate public interest to which article 23 of the Constitution applies.
The Court actively exercised its power in JY Interpretation No 567 (2003), which concerned the security framework of the former regime.Footnote 125 In this decision, the TCC was emphatic that even in times of exceptional upheaval, the minimum core of constitutional freedoms and protections must remain protected.Footnote 126 This decision addressed an administrative ordinance, the Disciplinary Measures Governing the Prevention of Recidivism by Communist Espionage Criminals during the Period of National Mobilisation for the Suppression of Communist Rebellion. This ordinance empowered intelligence agencies to impose indefinite periods of re-education and disciplinary measures on political prisoners after they had completed their sentences. The Court invalidated parts of the ordinance, holding that it infringed upon individuals’ personal freedoms guaranteed under article 8 of the ROC Constitution; this required restrictions on an individual’s personal freedoms to be decided by courts, not intelligence agencies.Footnote 127
In addition, the TCC has also dealt with three areas of national security cases: (1) conscientious objection; (2) other issues related to military service; and (3) freedom of expression.
Conscientious objection. Article 137 of the ROC Constitution stipulates that the objective of the ROC’s national defence is to safeguard national security and preserve world peace. Article 20 of the ROC Constitution provides for citizens’ obligation to perform military service. Nevertheless, how this obligation can be reconciled with citizens’ freedom of religion guaranteed by article 13 of the Constitution remains a critical question in Taiwan. This dilemma is particularly challenging, given that article 1 of the Military Service Act, its implementing regulations, and other statutes governing military service stipulate that all male citizens above the age of eighteen are obligated to perform military service, and failure to do so may result in criminal punishment.
In JY Interpretation No 490 (1999), the TCC addressed petitions filed by four Jehovah’s Witnesses who refused to perform military service on the ground that it violated their religious beliefs and freedom of conscience. As a result of their refusal, these petitioners were convicted, some multiple times, and sentenced to varying terms of punishment.Footnote 128
In response, the TCC ruled that article 1 of the Military Service Act was constitutional in imposing the obligation of military service exclusively on male citizens. The Court emphasised that freedom of religion encompasses both the ‘freedom to hold internal beliefs’ and the ‘freedom to act in accordance with those beliefs’. While the former is absolute, the latter may be subject to legitimate and necessary regulation.Footnote 129 Moreover, to implement article 20 of the Constitution, the legislature is entitled to enact relevant statutes taking into account the necessity of national security and social development, including the adoption of male-only military service obligations. In the TCC’s view, the legislative purpose of article 1 was to realise national objectives and citizens’ constitutional duties, and it constituted a necessary means of protecting citizens and national security. The Court further reasoned that, because article 1 did not in itself directly interfere with the exercise of religious freedom, it was compatible with the Constitution.Footnote 130
Other issues related to military service. In JY Interpretation No 443 (1997), the Court invalidated an administrative rule issued by the Ministry of Domestic Affairs, which violated draftees’ freedom of residence and migration by prohibiting them from leaving the country.Footnote 131 The Court in that case developed a hierarchical framework under the principle of Gesetzesvorbehalt, demanding varying levels of legislative authorisation based on the significance of individual freedoms or public affairs.Footnote 132 For example, an individual’s personal freedom can only be restricted under article 8 of the Constitution with prior judicial authorisation, and a writ of habeas corpus must be available. In addition, an individual’s other constitutional rights and freedoms can only be restricted by law or by administrative rules explicitly authorised by law. Finally, executive agencies may adopt internal guidelines to regulate technical matters related to law enforcement, if such guidelines impose only minor restrictions on the exercise of their rights and freedoms.Footnote 133 Based on the Court’s interpretation, the freedoms of residence and movement fell within the second tier and, therefore, required specific authorisation from the legislature.
In JY Interpretation No 517 (2000), the TCC ruled that several provisions of the Punishment Act for Violations of Military Service System (the Punishment Act) were constitutional.Footnote 134 These provisions imposed criminal liability on individuals who, without justifiable grounds, failed to comply with a military call-up because they had failed to report a change in residence.Footnote 135 While the plaintiffs argued that such criminal liability disproportionately infringed upon their freedoms of residence and migration, the TCC held that the protection of national security and national defence is regarded as a prerequisite for the effective exercise of citizens’ fundamental rights; unless the legislature violates the principle of proportionality, it enjoys broad discretionary power to determine the means of protecting national security and national defence. When exercising this discretion, the legislature can make decisions based on the importance of military service to national defence, the seriousness of violations of military service obligations, and the impact of punishment on individual rights. Therefore, the legislature was deemed competent to determine whether violations of military service obligations should give rise to criminal sanctions or administrative penalties.Footnote 136
Applying the principle of proportionality, the Court reasoned as follows. First, the contested provisions served significant national security interests. Second, criminal penalties were appropriate and necessary to ensure the effective management of the call-up system, which could not be achieved through administrative penalties, as might be possible in other regulatory contexts. Finally, because courts could determine the severity of punishment on a case-by-case basis in light of the gravity of each violation, the contested provisions did not impose an excessive restriction on citizens’ freedoms. On this basis, the contested provisions of the Punishment Act were held to be constitutional.Footnote 137
In JY Interpretation No 715 (2013), the TCC invalidated a recruitment guideline issued by the Ministry of Defence.Footnote 138 This guideline prohibited individuals with a criminal record from registering for the examinations for the reserve military forces or reserve military non-commissioned officers, regardless of whether the conviction arose from an intentional or negligent criminal offence, whether the individual had committed repeated crimes, or whether the offence was an isolated occurrence with limited consequences.Footnote 139
The TCC declared that while the Ministry of Defence was empowered by the Military Service Act to issue the guideline, thereby complying with the principle of Gesetzesvorbehalt, its exercise of power had to comply with the principle of proportionality. Indeed, the purpose of this prohibition was legitimate, as it aimed to ensure the integrity and quality of students at military schools.Footnote 140 Also, the prohibition was necessary to maintain the quality of the armed forces and enhance their efficacy.Footnote 141 Nevertheless, the prohibition invariably restricted all individuals with a criminal record. By failing to differentiate the impact of different criminal convictions on an applicant’s suitability and their eligibility to register for the examination, it was not the least intrusive means of protecting national security and thereby violated the constitutional right of individuals to hold public office under article 18 of the Constitution.Footnote 142 Accordingly, the TCC urged the Ministry of Defence to update its examination rules to safeguard constitutional rights while also enhancing national security.Footnote 143
Freedom of expression. JY Interpretation No 445 (1998) dealt with the prior-restraint regime under Taiwan’s old Assembly and Parade Act (TWAPA) of 1988,Footnote 144 which was enacted one year after martial law was lifted, alongside the Civil Associations Act (TWCAA). These were adopted with the explicit twofold aim of protecting national security and maintaining social order.Footnote 145 Under these Acts, assembly activities and the establishment of civil associations required the approval of local governments. Article 11 of the TWAPA stipulated the circumstances in which police departments could impose a prior restraint, including with respect to assemblies and parades advocating ‘communism’ and ‘secession of the national territory’. Article 11 also empowered police departments to impose a prior restraint on assemblies and parades that jeopardised national security, social order, or the public interest.Footnote 146
Notably, the ‘national territory’ in this provision did not refer to Taiwan and its adjacent islands; instead, it referred to the whole territory of China that the KMT government had claimed throughout more than thirty years of authoritarian rule.Footnote 147 Based on this interpretation of the text, the TWAPA targeted not only expressive acts associated with communism but also those that could be viewed as advocating Taiwan’s independence.Footnote 148
In JY Interpretation No 445, the Court criticised prior restraints under article 11 as extremely vague. The Court explicitly invoked the principle of clarity with respect to the invalidated parts of article 11, holding that those provisions violated citizens’ freedom of expression and freedom of assembly.Footnote 149 Nevertheless, it remained unclear whether the justices agreed with the political branches’ position that the TWAPA was primarily intended to serve national security purposes. The Court remained silent on whether advocating for ‘communism’ and ‘secession of the national territory’ could be regulated under the TWAPA. Accordingly, it remains unclear whether the police could regulate advocacy of communism or secession of the national territory or other political activities through more narrowly tailored restrictions.Footnote 150
Ten years later, the Court dealt with a similar case concerning the TWCAA in JY Interpretation No 644 (2008).Footnote 151 Article 2 of the TWCAA prohibited civil associations advocating for communism or secession of the national territory, and the first part of article 53 empowered executive agencies to disapprove the establishment of civil associations of this kind. In this decision, the Court was silent about the TWCAA’s relevance to national security. However, in a concurring opinion, Justice Lin Tzu-Yi held that national security could not be seen as a legitimate purpose of the TWCAA under Taiwan’s democratic regime.Footnote 152 Moreover, based on the principle of proportionality, the Court ruled that prohibiting citizens from establishing certain organisations based on particular ideologies was an excessive and therefore unconstitutional restriction. The Court thus struck down article 2 and the first part of article 53 because they disproportionately restricted individuals’ freedoms of expression and association.Footnote 153
A comparative analysis of the KCC and the TCC
Similarity
There are both general- and case-based similarities in the KCC’s and TCC’s jurisprudence. At a general level, both Courts addressed governmental measures imposed by authoritarian regimes in the name of national security and emergency. Moreover, both Courts adjudicated three main types of national security disputes: (1) conscientious objection; (2) other issues related to military service; and (3) freedom of expression. In reviewing these disputes, the Courts relied on similar modes of reasoning, including the principles of proportionality and clarity, as well as legal concepts such as legislative discretion and the distinction between absolute and relative freedom. In several cases, the two Courts also reached comparable conclusions regarding the permissible bounds of governmental power in the realm of national security.
Among these categories, the two Courts’ jurisprudence on conscientious objection reveals a significant degree of case-based similarity. This similarity is relatively weaker, but still strong, in their approaches to other issues related to military service. Turning first to conscientious objection, both the KCC (in 2002Hun-Ka1) and the TCC (in JY Interpretation No 490) considered freedom of conscience or religion to be a relative right, subject to governmental intervention on justifiable grounds. In particular, both Courts recognised that the legislature enjoys broad discretion in formulating national security policies in relation to mandatory military service – a field that involves various constitutional and technical considerations. The legislature’s decision not to provide alternative service programmes was regarded as resting on legitimate and reasonable grounds, in light of each country’s national security conditions, military structures, and related considerations. The Courts further held that such legislative choices did not impose undue burdens on the petitioners, thereby reflecting a permissible balance between the public interest pursued and the restriction of individual freedoms.Footnote 154 Although the KCC later adopted a more progressive stance in 2011Hun-Ba379 by demanding that the government adopt alternative service programmes, its reasoning regarding the punishment of conscientious objectors remains largely consistent with the doctrinal framework it established in 2002Hun-Ka1.
Regarding other issues related to military service, the TCC’s JY Interpretation No 517 is analogous to the KCC’s 2012Hun-Ba258, as well as other decisions related to the prohibition of same-sex sexual contact in the military.Footnote 155 In these two lines of decisions, both Courts emphasised national security as a prerequisite for citizens’ lives and safety. They further stressed that the legislature enjoys broad discretion in maintaining the effective functioning of the military system for that purpose.
In applying the principle of proportionality, the Courts reasoned that failure to comply with a call-up notice (as in JY Interpretation No 517) or the commission of ‘disgraceful or indecent’ sexual acts (as in 2012Hun-Ba258) would pose significant challenges to the operation and discipline of the military. Such conduct, in the Courts’ view, could not be effectively deterred through administrative measures, as such measures would not achieve a deterrent effect comparable to that of criminal punishment. On this basis, both Courts concluded that the criminal punishment at issue was legitimate, appropriate, and necessary. Moreover, the resulting restrictions on individual freedoms were not considered disproportionate to the public interests pursued.Footnote 156
Difference
While the two Courts share certain similarities, they have also demonstrated divergent approaches in adjudicating national security disputes. This divergence is evident not only in their reasoning and outcomes in individual cases, but also in their broader constitutional understandings of national security.
Consider first cases regarding authoritarian governmental measures, namely, the KCC’s 2010Hun-Ba132 and the TCC’s JY Interpretation No 567. At first glance, both Courts appeared to adopt a progressive stance, emphasising limits on state power even in times of crisis.Footnote 157 Nevertheless, the two decisions arose within fundamentally different legal contexts, giving them distinct constitutional significance. The KCC dealt with the constitutionality of emergency decrees promulgated by the president, directly confronting the legality of authoritarian emergency governance. By contrast, the TCC addressed the protection of constitutional rights in the post-democratisation period without directly challenging the core legitimacy of the former regime.Footnote 158 In this sense, the KCC played a more active role in reckoning with South Korea’s authoritarian past by declaring the emergency decrees unconstitutional.
Nevertheless, the KCC’s active posture in the context of emergency decrees did not extend to cases involving contemporary national security concerns. In the context of military service, the KCC adopted a deferential approach, diverging from the TCC’s jurisprudence in JY Interpretation No 443 (regarding an administrative rule restricting draftees’ freedoms of residence and migration) and JY Interpretation No 715 (regarding an administrative guideline specifying eligibility for military recruitment).
In JY Interpretation No 443, the TCC articulated and applied the principle of Gesetzesvorbehalt, requiring an appropriate level of legislative authorisation for different forms of administrative rules. The administrative rule at issue was invalidated because it restricted citizens’ freedoms of residence and migration without a sufficient statutory basis.Footnote 159 In JY Interpretation No 715, although the TCC found that the guideline formally satisfied the principle of Gesetzesvorbehalt, it nonetheless held it unconstitutional on proportionality grounds. By imposing a blanket prohibition on individuals with criminal records from registering for the examination, the measure was deemed to impose an excessive restriction on individual rights.Footnote 160
Perhaps the most pronounced case-based difference between the KCC and the TCC emerges in the context of freedom of expression. In 89Hun-Ka113, the KCC acknowledged that article 7 of the SKNSA unconstitutionally empowered law enforcement agencies to prosecute individuals or silence the public sphere in the name of national security. However, the Court invoked the doctrine of conditional constitutionality to uphold article 7 under a narrower interpretation, justifying its decision by reference to South Korea’s ongoing military conflicts with North Korea.Footnote 161 This line of reasoning was subsequently reaffirmed, as the KCC repeatedly emphasised that South Korea’s geopolitical circumstances rendered several provisions of article 7 appropriate and necessary for the protection of national security.Footnote 162 Because the public interest served by criminal punishment was not outweighed by the infringement of individuals’ political freedoms, those provisions were deemed constitutional.Footnote 163
By contrast, in JY Interpretations Nos 445 and 644, the TCC adopted a markedly more protective stance in cases related to prior restraints on freedom of expression, assembly, and association. To be sure, criminal punishment and prior restraint may call for different balancing exercises with respect to public interests and individual rights. Even so, the TCC did not foreground the particular salience of national security when reviewing regulations that empowered law enforcement agencies to impose prior restraints on parades, assemblies, or the establishment of associations. Instead, it focused on the impact of such prior restraints on citizens’ political freedoms, reasoning that they constituted the most intrusive form of restrictions on rights and therefore must be subject to strict scrutiny. Accordingly, the TCC concluded that the regulations at issue unconstitutionally granted excessive power to law enforcement agencies.Footnote 164
The divergent approaches of the KCC and the TCC to freedom of expression highlight a broader distinction in their general national security jurisprudence. The KCC frequently integrates the country’s particular security conditions and military tensions into its application of constitutional principles, whereas the TCC focuses on whether a broadly defined ‘national security interest’ can justify rights restrictions. For instance, in cases concerning conscientious objection, the KCC justified the legislature’s broad discretion by emphasising South Korea’s acute security needs. In military service cases, the KCC stressed that criminal punishment for ‘indecent sexual acts’ was necessary under a proportionality analysis, largely because South Korea’s security situation complicates the maintenance of military discipline. Similarly, in freedom of expression cases, the KCC placed substantial weight on the geopolitical tensions on the Korean Peninsula. In this sense, the KCC adopts a more contextualised approach, grounding its legal assessments in – and frequently justifying them by reference to – South Korea’s own security circumstances.
By contrast, the TCC gives relatively little consideration to Taiwan’s specific geopolitical conditions, however defined. Instead, it typically grounds its national-security-related decisions in broad and general claims about national security interests, leaving questions concerning Taiwan’s particularity unattended. Indeed, in several decisions, such as those related to election lawFootnote 165 or family law,Footnote 166 the TCC elaborated on how the confrontation across the Taiwan Strait could serve as a potential justification for governmental regulation. Yet these areas of law were not designed primarily to serve national security objectives. As a result, references to national security in such cases function, at most, as ancillary or incidental commentary on national security law, rather than as the central basis of constitutional reasoning.
Under this approach, the TCC does occasionally uphold governmental intervention, as in JY Interpretation Nos 490 and 517. Nevertheless, national security is consistently treated as a general public interest. For instance, in JY Interpretation No 445, the TCC did not differentiate the application of the principle of clarity between measures adopted for reasons of national security, social order, or other public interests.Footnote 167 In JY Interpretation No 715, national security considerations failed to justify the regulatory instrument at issue, because the TCC identified less intrusive means capable of achieving the same security objectives.Footnote 168 In short, the TCC did not invoke national security as a justificatory factor reinforcing governmental regulation to the same extent as the KCC did in the Korean context.
Consequence
One consequence of this divergence is that the two Courts play different roles in determining the extent to which past national security laws may extend into the present. The KCC’s sustained focus on South Korea’s geopolitical conditions has the effect of legitimising broader governmental intervention on the basis of contemporary and ostensibly genuine security needs. Nevertheless, national security laws and institutions in post-transition societies are often embedded in legal practices and institutional norms associated with authoritarian governance, including histories of human rights abuses (such as the prosecution of conscientious objectors) and systematic discrimination against political dissidents or sexual minorities (such as article 7 of the SKNSA or the criminalisation of same-sex sexual conduct).Footnote 169 As such, the KCC’s deferential approach to national security law creates a grey zone in which authoritarian legacies may intersect with – and be rearticulated through – contemporary security imperatives.Footnote 170 Even though national security does not always justify a restriction on individual freedoms, the KCC’s contemporary security jurisprudence risks incorporating elements of the authoritarian past into South Korea’s existing security framework, an ostensibly neutral framework necessary for the country’s survival in the face of potential attacks from North Korea.Footnote 171
By contrast, because national security does not occupy a comparably privileged position in the TCC’s jurisprudence, the Court appears more willing to invalidate security narratives inherited from the pre-democratisation period and to replace them with general legal principles governing the government’s exercise of power, including in the national security context. The TCC’s emphasis on ordinary constitutional principles thus stands in sharp contrast to the security-first logic embedded in Taiwan’s authoritarian past. JY Interpretation No 644 provides a particularly vivid illustration: although the TWCAA was originally adopted primarily for security reasons shortly after martial law was lifted, the TCC did not invoke national security in justifying its review of regulations governing the establishment of civil associations.Footnote 172 As such, the TCC appears to take a more sceptical posture with respect to the role of pre-transition narratives in contemporary security governance.
Hypothesis
What explains the different modes of referencing the specificity of national security interests exhibited by the KCC and TCC with respect to national security law? Although there may be numerous explanations, this article advances a possible explanation that lies in the two jurisdictions’ divergent security thinking in the aftermath of democratisation. In South Korea, while there has been a degree of democratisation in the realm of national security, the ‘realpolitik view of security’ as described by scholars has persisted.Footnote 173 This view emphasises the inevitable use of military institutions for state-building and self-defence, largely owing to military tensions and geopolitical competition on the Korean Peninsula.Footnote 174 This realpolitik view of security aligns with so-called ‘fundamentalist’ or ‘absolutist’ understandings of national security, which emphasise a zero-sum competition between the South and the North: as long as North Korea exists, there will be a constant threat to the security of South Korea.Footnote 175 This ‘fundamentalist’ understanding of national security may have prompted the KCC to recognise the weight of certain core elements of national security across different democratic governments.Footnote 176
The ‘dual structure’ established by articles 3 and 4 of the Constitution may also play a role in shaping how the KCC assesses the weight accorded to national security.Footnote 177 To be sure, on the basis of article 4, the KCC and the Supreme Court of Korea have acknowledged North Korea as a counterpart for dialogue and cooperation as stipulated in the Inter-Korean Basic Agreement and related laws.Footnote 178 Nevertheless, this acknowledgment does not amount to official recognition of North Korea as an official ‘partner’. Moreover, it does not alter the continuing salience of article 3, which stipulates that the territory consists of the Korean Peninsula and its adjacent islands. For these reasons, the Supreme Court has often invoked article 3 as the basis for designating North Korea an anti-state organisation in criminal cases and rulings concerning the application of the SKNSA, and this position has been endorsed by the KCC.Footnote 179
By contrast, the TCC’s rare discussion of Taiwan’s security conditions may be explained by the constitutional ambiguity of Taiwan’s national boundaries as a product of post-war geopolitics. One important function of security institutions is to defend the territorial boundaries of the state. Nevertheless, as a ‘contested state’,Footnote 180 the territorial boundaries of the ROC remain unclear. As discussed above, the 1991 constitutional amendment relied on ambiguous language such as the reference to the period ‘prior to national unification’, in addition to other provisions applying only to Taiwan and its adjacent islands, to recognise the status quo of Taiwan’s political reality. Even though these provisions recognised the Constitution as applying only to Taiwan and its adjacent islands, questions concerning the ROC’s territory and the preservation of sovereignty remain unresolved, in part owing to Taiwan’s contested international status.Footnote 181 Without a clear textual hook to endorse any particular version of territorial integrity, the TCC carefully avoids the issue, regarding it as a political question that cannot be reviewed through constitutional interpretation.Footnote 182 Perhaps for similar reasons, the Court seldom defines the nature of national security threats as directly as the KCC does.Footnote 183
There are also political questions about the national identity of Taiwan. During the Cold War period, the KMT government embraced Chinese orthodoxy, considering the ROC government in Taiwan to be the representative of China.Footnote 184 Based on this view, the KMT government not only competed with the CCP to represent China and silenced communist ideology but also considered those engaged in domestic activities in support of Taiwan’s independence to be enemies of the state. After democratisation, new political platforms emphasising Taiwan’s subjectivity became more powerful than ever. These platforms created a pluralistic landscape regarding Taiwan’s core identities and questions about how Taiwan’s national interests should be defined as well as the proper functions and responsibilities of security institutions.Footnote 185 As these questions remain contentious and debatable within the public sphere, perhaps the TCC has little incentive either to fixate on a particular understanding of threat and national security, or to reinforce governmental intervention on national security grounds.Footnote 186
The above examples demonstrate how the Constitutional Courts of South Korea and Taiwan have adjudicated national security law, relying on their respective understandings of security as well as general principles embodied in their Constitutions. The jurisprudence of the TCC and KCC offers underexplored perspectives about constitutional courts in East Asian democracies. While the existing literature emphasises the role of constitutional courts in promoting constitutionalism, this article demonstrates that post-transition constitutional courts such as the KCC and TCC also formulate conceptions of security and determine their normative weight within their respective democratic trajectories. By incorporating these concepts and justifications into their national security jurisprudence, the Courts explicitly or implicitly engage with authoritarian legacies embedded in national security laws originally adopted under the former authoritarian regimes. As a result, they have played a critical role in facilitating the ongoing process of constitutional negotiation between security and democracy within their respective contexts.
Recognising this role of constitutional courts is useful for understanding the relevance of authoritarian legacies in new democracies. Authoritarian legacies not only encompass institutions that persist across time; they also embody ideas about security, threats, and enemies of the state, which may evolve or persist over time. These legacies of authoritarianism are thus often called upon by contemporary politicians to serve partisan needs. Courts may, in response, undermine or reinforce the legitimacy of security institutions, substantially shaping the path-dependent structure of those institutions in the contemporary era.Footnote 187 The Korean example clearly shows how contemporary needs for security based on genuine geopolitical confrontations and security threats have strengthened the legitimacy of security institutions.Footnote 188 By contrast, amid renewed public awareness of Taiwan’s security, politicians and the public are in the process of searching for a new balance between security and democracy.Footnote 189 Perhaps when the TCC encounters difficult cases in this area, its responses will reveal important lessons concerning whether, and to what extent, legacies of authoritarianism will be retained or discarded.
Conclusion
Scholars of comparative constitutional law have extensively examined how authoritarian governments rely on national security law to maintain political stability and social order. In contrast, there are few studies of national security law in new democracies, which are often assumed to prioritise constitutional values over authoritarian perspectives. In this article, I have demonstrated how the Constitutional Courts in democratic South Korea and Taiwan have reconfigured national security law by incorporating their divergent understandings of national security and the normative weight accorded to it into the application of proportionality principles, among other constitutional tools. In so doing, the Constitutional Courts have explicitly or implicitly shaped how legacies of authoritarianism embedded in pre-transition national security institutions interact with contemporary security governance. These Courts thus play a crucial role in facilitating the ongoing negotiation between security and democracy at the heart of post-transition constitutional development.
Future research could continue to explore authoritarian legacies in executive or legislative institutions. While this article focuses on the functions of courts, there is significant value in examining, for example, the institutional inertia of executive agencies or legislative chambers that can be traced back to authoritarian regimes. As authoritarian practices have become deeply ingrained in the operational practices of these institutions, state officials may lack ‘incentives to change’, resulting in policies that are ineffective rather than intentionally harmful.Footnote 190 Authoritarian legacies may take many forms and may reflect ‘malign intent’. Understanding the institutional inertia of state institutions can provide important insights into the state’s capacity constraints and may offer crucial lessons for strengthening the quality of state performance and improving the resilience of democratic governance in the future.
Future researchers could examine political leaders’ adoption of narratives that characterise the authoritarian past as the ‘good old days of stability, law and order’. In this article, I have demonstrated how constitutional courts have relied on different forms of security thinking to shape the relationship between authoritarian legacies and contemporary security governance. However, before constitutional courts become involved in resolving disputes, politicians often utilise arguments about threats and security to reinforce authoritarian legacies. Especially in an era of democratic backsliding, politicians worldwide have manipulated the public’s sense of fear, stifled political debate in the public sphere, and concentrated state power to serve their political ambitions. As such, the study of authoritarian legacies requires not only a closer look at the operations of constitutional institutions but also a careful examination of the interplay between politicians and the public. This study of national security law in South Korea and Taiwan offers valuable, though necessarily partial, answers and hopefully opens avenues for further discussion on the interplay between national security, democracy, and constitutionalism.
Supplementary material
The supplementary material for this article can be found at https://doi.org/10.1017/asjcl.2026.10050.
Open access
