Q: How are constitutional norms characterized in Japan, and what are their primary sources beyond the written text?

The Constitution of Japan, like that of many nations, is more than just its codified text. While the written document forms the bedrock of the nation's legal order, the full scope of Japanese constitutional norms is shaped by their inherent characteristics and supplemented by unwritten sources that play a crucial role in its interpretation and evolution. This article explores the defining features of constitutional norms in Japan and examines the significant unwritten sources—constitutional conventions and judicial precedents—that contribute to the living constitution.

The Defining Features of Constitutional Norms in Japan

Japanese constitutional law identifies three primary characteristics that define the nature and function of its constitutional norms (kenpō kihan). These features illuminate how the Constitution structures state power and safeguards fundamental rights.

1. Empowering Norms (授権規範 - Juken Kihan):
   Constitutional norms serve as empowering norms by establishing state organs and conferring specific powers upon them. For example, Article 41 of the Constitution designates the National Diet as "the highest organ of state power" and "the sole law-making organ of the State," thereby empowering it with legislative authority. Similarly, Article 65 vests executive power in the Cabinet. These provisions create the institutional framework of the state and authorize these bodies to act. The very existence and functioning of state institutions are predicated on these empowering norms. Some scholars also refer to these as "organizational norms" (soshiki kihan) as they create the organization of the state itself.
2. Limiting Norms (制限規範 - Seigen Kihan):
   In line with modern constitutionalism, constitutional norms also function as limiting norms, designed to restrict state power and protect the fundamental human rights of the people. The extensive Bill of Rights in Chapter III of the Constitution, guaranteeing freedoms such as expression, religion, and assembly, are prime examples of limiting norms. They define boundaries that state power cannot legitimately cross. While empowering norms grant authority, limiting norms ensure that this authority is not absolute and is exercised in a manner that respects individual liberties. There's an inherent duality, as an empowering norm also implicitly limits power to what is granted; however, specific limiting norms provide clearer safeguards against potential overreach.
3. Supreme Norms (最高規範 - Saikō Kihan):
   The Constitution itself declares its own supremacy. Article 98, paragraph 1, states: "This Constitution shall be the supreme law of the nation and no law, ordinance, imperial rescript or other act of government, or part thereof, contrary to the provisions hereof, shall have legal force or validity". This characteristic flows from the Constitution's nature as a "rigid" or "entrenched" constitution (硬性憲法 - kōsei kenpō), meaning its amendment procedure (Article 96) is significantly more stringent than that for ordinary laws. This formal supremacy places the Constitution at the apex of the domestic legal hierarchy, and all other legal norms must conform to its provisions. The formal basis for this supremacy is often linked to Article 96, while its substantive basis is found in principles like the guarantee of fundamental human rights (Article 97).

The Hierarchy of Written Laws

The Japanese legal system is often visualized as a pyramid, with the Constitution at its zenith. This hierarchical structure, influenced by thinkers like Hans Kelsen, implies that lower-ranking legal norms derive their validity from higher-ranking ones. Any conflict between norms of different levels is resolved by invalidating the subordinate norm that contradicts the superior one. Key written sources of law, subordinate to the Constitution, include:

• Statutes (法律 - Hōritsu): Enacted by the National Diet, the sole law-making organ. They are the primary means of regulating rights and obligations and implementing constitutional provisions.
• Cabinet Orders (政令 - Seirei): Issued by the Cabinet to execute constitutional and statutory provisions (Article 73, item 6). These cannot impose duties or restrict rights without statutory delegation.
• Ministerial Ordinances (省令 - Shōrei) and Rules (規則 - Kisoku): Issued by heads of executive agencies.
• Rules of the Houses of the Diet (議院規則 - Giin Kisoku) and Rules of the Supreme Court (最高裁判所規則 - Saikōsaibansho Kisoku): These bodies have rulemaking authority over their internal procedures and administration (Articles 58 and 77 respectively).
• Local Ordinances (条例 - Jōrei): Enacted by local public entities within the scope of laws (Article 94).
• Treaties (条約 - Jōyaku): International agreements concluded by the Cabinet and requiring Diet approval in principle (Article 73, item 3). Their domestic effect and relationship with the Constitution are complex, with the prevailing view holding the Constitution superior.
• The Budget (予算 - Yosan): Considered a unique legal norm, distinct from statutes, that authorizes state revenue and expenditure for a fiscal year.

Beyond these, a category of laws known as "laws appurtenant to the Constitution" (憲法附属法 - kenpō fuzoku-hō)—such as the Imperial Household Law, Diet Law, and Cabinet Law—are considered to contain provisions that are substantively constitutional in nature, playing a key role in shaping the constitutional order.

The Crucial Role of Unwritten Sources

While the written Constitution is central, its interpretation and application are significantly influenced by unwritten sources of law. These sources provide flexibility and allow the Constitution to adapt to changing societal conditions. The two primary unwritten sources are constitutional conventions and constitutional case law.

Constitutional Conventions (憲法慣習 - Kenpō Kanshū)

Constitutional conventions are unwritten rules of political practice that are regarded as binding by those to whom they apply. They arise from repeated practices accompanied by a sense of legal obligation (opinio juris).

• Formation and Effect: A mere custom or practice (kanshū) evolves into a constitutional convention (kenpō kanshū) when it gains a normative character—a belief that it ought to be followed. While general Japanese law (e.g., Article 3 of the Act on General Rules for Application of Laws; Article 92 of the Civil Code) gives limited effect to customs, usually supplementary to or in the absence of statutory provisions, some scholars argue that the binding force of both enacted law and customary law ultimately derives from the legal conviction of the people, implying no inherent superiority of enacted law. This could allow for conventions that even modify mandatory provisions of law.
• Distinction from Constitutional Practices/Usages (憲法習律 - Kenpō Shūritsu): It's important to distinguish constitutional conventions, which are considered to have legal force and bind all state organs including courts, from mere constitutional practices or usages (kenpō shūritsu). The latter may politically constrain organs like the Diet or Cabinet but are not considered legally binding on courts. Examples under the Meiji Constitution included the practice of the majority party in the House of Representatives forming the Cabinet, or consulting elder statesmen (Genrō) on the formation of a new cabinet. Under the current Constitution, the Emperor's speech at the opening of the Diet or the Prime Minister typically being a member of the House of Representatives are sometimes cited as shūritsu.
• Types and Formal Validity:
  • Conventions filling gaps in the written Constitution: These are widely recognized. Their formal validity (i.e., whether they can be altered by ordinary law or require constitutional amendment) is debated. Some argue they can be changed by statute, similar to general customs.
  • Conventions conflicting with express constitutional provisions: This is a more contentious area and relates to the concept of "constitutional transformation" (kenpō hensen). If such a convention, rooted in the people's legal conviction, arises, it effectively supersedes the conflicting written provision, which loses its validity. Such a convention would have a formal validity equivalent to the written Constitution and could only be altered by constitutional amendment.

The line between these types can be blurry, depending on how narrowly or broadly one interprets the "gaps" in the written Constitution.

Constitutional Case Law (憲法判例 - Kenpō Hanrei)

Judicial precedents, particularly those of the Supreme Court, form another vital unwritten source of constitutional law in Japan. While Japan is a civil law country where statutes are the primary source of law, the practical and theoretical impact of Supreme Court decisions on constitutional matters is undeniable.

• Nature of "Hanrei": A "precedent" (hanrei) refers to the legal reasoning (ratio decidendi) essential for the conclusion (main text or shubun) of a court judgment, as distinct from obiter dicta (collateral opinions). When a court, especially the Supreme Court, provides a well-reasoned legal interpretation to resolve a specific case, subsequent similar cases are likely to be decided in the same way to ensure consistency and legal stability.
• Binding Force: The legal binding force (hōgensei) of precedents is a subject of ongoing debate in Japanese jurisprudence. The traditional majority view holds that precedents only have de facto binding force on lower courts, not de jure. However, an increasingly influential view argues for recognizing their legal binding force, emphasizing the principle of equality (like cases should be treated alike). The Supreme Court's decisions do legally bind lower courts in the specific case remanded (Article 4 of the Court Act), and the Code of Civil Procedure makes contradiction with Supreme Court precedents a ground for acceptance of final appeal (Article 318, para. 1).
• Distinctiveness of Constitutional Precedents: Constitutional precedents are unique because, unlike precedents on ordinary statutes which can be altered by legislative amendment, they can generally only be changed by the Supreme Court itself or through a constitutional amendment. This gives constitutional precedents a quasi-constitutional status. If a court derives a rule from its interpretation of the Constitution and uses that rule to judge the constitutionality of a statute, that rule effectively operates as a norm superior to the statute. Thus, the formal validity of a constitutional precedent is considered equivalent to that of the written Constitution itself.
• Modification of Constitutional Precedents: The Supreme Court can change its own precedents, but this requires deliberation by the Grand Bench (Article 10, item 3 of the Court Act). There is debate on whether constitutional precedents should be changed more readily than ordinary ones. One view, expressed in a concurring opinion in the Zennōrin Keishoku-hō Case (Grand Bench, April 25, 1973), emphasizes the need for extreme caution, as changing constitutional interpretations can be tantamount to amending the Constitution itself and can affect the authority and stability of the constitutional order. Conversely, other scholars argue for greater flexibility, since constitutional precedents, unlike statutory ones, cannot be easily overridden by the Diet, and adapting the Constitution to changing times through interpretation is preferable to frequent formal amendments.
• Retroactive Effect of Changed Precedents: A complex issue arises when the Supreme Court overturns a previous precedent. Applying a new, unfavorable interpretation retroactively to actions taken in reliance on the old precedent can raise due process concerns (Article 39). While some scholars advocate for the "non-retroactive modification of precedents," the Supreme Court has not always adopted this approach (e.g., Supreme Court judgment, November 18, 1996).

Conclusion: A Dynamic Constitutional Order

In conclusion, constitutional norms in Japan are characterized by their empowering, limiting, and supreme nature. While the written Constitution is the paramount source, its meaning and application are continuously shaped and enriched by unwritten sources. Constitutional conventions, born from established practices and a sense of legal obligation, fill gaps and can even reflect fundamental shifts in the constitutional understanding. Similarly, constitutional case law, through the authoritative interpretations of the Supreme Court, clarifies constitutional provisions, resolves ambiguities, and adapts the Constitution to new challenges. This interplay between the written text and these dynamic unwritten sources ensures that Japan's constitutional order remains a living framework, capable of guiding the nation while responding to the evolving needs of its state and society.