"The Court Only Considers What Parties Argue": How Does the "Principle of Party Presentation" (Benron-shugi) Shape Japanese Civil Litigation?

Navigating civil litigation in any foreign jurisdiction requires a fundamental understanding of its core procedural principles. In Japan, one of the most pivotal concepts shaping the conduct of civil lawsuits is the "Principle of Party Presentation," known in Japanese as Benron-shugi (弁論主義). This principle essentially dictates that the parties to a lawsuit—not the court—are primarily responsible for introducing the factual allegations and evidence that will form the basis of the court's decision. For any entity, including a U.S. company, involved in Japanese litigation, grasping the implications of Benron-shugi is crucial for effective case strategy and presentation.

This article explores the intricacies of Benron-shugi, examining its core tenets, underlying rationale, and the practical ways in which it influences the entire lifecycle of a civil case in Japan, from pleadings to judgment.

Understanding Benron-shugi: Core Idea and Rationale

At its heart, Benron-shugi signifies a division of labor in the courtroom: the parties furnish the "litigation materials" (soshō shiryō)—that is, the factual claims and the supporting evidence—while the court's role is to adjudicate the dispute based on the materials presented by these parties. This contrasts with a purely inquisitorial system where the court might independently investigate facts and gather evidence.

The adoption of Benron-shugi in Japanese civil procedure is underpinned by several rationales:

• Private Autonomy (J.: shiteki jichi; Honshitsu-setsu - Essential Nature Theory): Since civil disputes typically involve private rights and interests, the parties concerned should have the autonomy to decide which facts and evidence to bring before the court. The court's intervention in defining the factual scope of a private dispute is generally limited.
• Efficient Truth Discovery (J.: Shudan-setsu - Means Theory): It is presumed that the parties, having the most at stake, are best motivated and positioned to gather and present all relevant information favorable to their respective positions. This adversarial presentation is thought to be an efficient means of arriving at the truth.
• Pluralistic Foundations (J.: Tagen-setsu - Pluralistic Theory): Many scholars view Benron-shugi not as a product of a single rationale but as a historical construct emerging from a confluence of factors, including private autonomy, the pursuit of truth, the prevention of judicial surprise, and the maintenance of public trust in the judiciary.

It's important to distinguish Benron-shugi from a related principle, Shobunken-shugi (処分権主義 - the Principle of Party Disposition). While both stem from private autonomy, Shobunken-shugi concerns the parties' control over the initiation, definition of the subject matter (the claim itself), and termination of the lawsuit. Benron-shugi, on the other hand, pertains to the parties' control over the factual and evidentiary content presented within that defined subject matter.

The Three Pillars of Benron-shugi

The practical application of Benron-shugi is traditionally understood through three main components or "theses":

Pillar 1: Party Assertion of Facts – The Court Cannot Go Beyond What is Alleged

The first, and arguably most fundamental, pillar is that the court cannot base its judgment on facts that have not been asserted by at least one of the parties. Even if evidence presented during the proceedings happens to reveal a potentially relevant fact, if neither party has formally alleged that fact as part of their case, the court is generally precluded from considering it in its decision-making process. The Supreme Court of Japan affirmed this in a judgment on February 7, 1980, distinguishing between facts asserted by parties (litigation materials) and facts that might incidentally emerge from evidence (evidentiary materials) but are not asserted.

This leads to the concept of Shuchō Sekinin (主張責任 – responsibility or burden of assertion). A party that fails to assert a fact that is essential to support its claim or defense bears the risk that the court will proceed as if that fact does not exist, potentially leading to an unfavorable outcome.

However, once a fact is asserted by either party, it becomes part of the "record" for the court's consideration, a concept known as the "principle of common assertion" (shuchō kyōtsū no gensoku). This means the court can rely on a fact asserted by the plaintiff even if it benefits the defendant, and vice versa, provided it has been duly introduced into the proceedings (Supreme Court judgment, September 8, 1966).

The scope of this first pillar primarily extends to "principal facts" (shuyō jijitsu) – those facts that are directly necessary under substantive law to establish a right or legal effect (e.g., the conclusion of a contract, the occurrence of a negligent act, the payment of a debt). It generally does not apply with the same rigor to "indirect facts" (kansetsu jijitsu – facts from which principal facts can be inferred) or "auxiliary facts" (hojo jijitsu – facts bearing on the credibility of evidence). This distinction allows the court greater freedom in evaluating evidence and drawing inferences under the principle of free evaluation of evidence (CCP Art. 247) without being unduly constrained by the parties' specific assertions of every minute evidentiary detail.

A nuanced area involves "normative requirement elements" (kihanteki yōken yōso) found in statutes, such as "negligence" or "just cause." In such cases, the specific, concrete facts that form the basis for these normative evaluations (hyōka konkyo jijitsu) are generally treated as principal facts that must be asserted by the parties to avoid unfair surprise. For instance, while the legal application of concepts like "public policy" or "good faith" is ultimately for the court, the specific underlying facts supporting such a contention must be introduced by the parties (Supreme Court judgment, April 27, 1961).

Pillar 2: Binding Effect of Judicial Admissions – Facts Not in Dispute

The second pillar dictates that facts which are explicitly admitted by a party in court, or which are alleged by one party and not disputed by the other, are binding on the court. Such an admission is termed a "judicial admission" (saibanjo no jihaku). The court cannot make findings contrary to these admitted facts, and no further proof of such facts is required (CCP Art. 179).

For a judicial admission to be effective, it typically must:

• Be made during oral arguments or formal preparatory proceedings.
• Concern a fact asserted by the opposing party.
• Be disadvantageous to the admitting party. (Case law, such as a Great Court of Cassation judgment of February 9, 1933, has interpreted "disadvantageous" as relating to facts for which the opposing party bears the burden of proof ).

Judicial admissions generally have an effect of excluding the court's power to adjudicate the admitted fact (shinpan haijo kō) and also render proof of that fact unnecessary (shōmei fuyō kō). Moreover, they are generally irrevocable (fukatekkai kō) to ensure procedural stability and protect the reliance of the opposing party. However, exceptions to irrevocability exist, such as when the admission was induced by the criminal act of another person (parallel to grounds for retrial under CCP Art. 338(1)(v)), with the opponent's consent, or, significantly, if the admission is contrary to the manifest truth and was made due to a mistake (Great Court of Cassation judgment, September 29, 1915). If it is proven that the admission is contrary to the objective truth, a mistake in making the admission is often presumed (Supreme Court judgment, July 11, 1950).

Like the first pillar, the binding effect of judicial admissions primarily applies to principal facts. Admissions regarding indirect facts or auxiliary facts are generally not considered to bind the court's evaluation of evidence (Supreme Court judgment, September 22, 1966, for indirect facts; Supreme Court judgment, April 15, 1972, for auxiliary facts). "Admissions of law" (kenri jihaku), such as admitting the existence of a right, are also treated differently; while they may relieve the opponent of the need to initially prove the right, they do not entirely preclude the court's own assessment of the legal situation, and such admissions are generally considered retractable (Supreme Court judgment, July 5, 1955).

Pillar 3: Prohibition of Ex Officio Evidence Examination – Parties Proffer Evidence

The third pillar states that the court, when determining disputed facts, must generally rely on evidence proffered by the parties. The court cannot, as a general rule, initiate an examination of evidence on its own motion (ex officio) if neither party has requested it. This reinforces the parties' role in shaping the evidentiary record.

However, this pillar has some notable statutory exceptions. For example, the court has the authority to examine the parties themselves as evidence ex officio (CCP Art. 207(1)). Also, the court can ex officio request expert opinions in certain circumstances, and its power to clarify (discussed below) can involve prompting parties to submit necessary evidence.

The Complementary Role: The Court's Power of Clarification (Shakumeiken)

Benron-shugi, if applied too rigidly, could lead to unjust outcomes, especially if one party is less sophisticated or overlooks crucial points. To mitigate this, and to ensure that the dispute is properly understood and adjudicated, the Japanese CCP grants the court a "power of clarification" (Shakumeiken - 釈明権, CCP Art. 149).

This power allows (and in some cases, obligates) the presiding judge to actively engage with the parties to clarify the litigation relationship (soshō kankei). This can involve:

• Asking questions regarding factual or legal assertions made by the parties.
• Pointing out ambiguities, inconsistencies, or omissions in their pleadings or oral statements.
• Prompting parties to make necessary assertions or to proffer relevant evidence.

The Supreme Court has held that this power is not merely discretionary but can also constitute a duty (shakumei gimu) of the court (e.g., Supreme Court judgment, June 26, 1964). Failure to exercise this duty appropriately, leading to an incomplete or flawed deliberation, can be a ground for reversal on appeal.

The power of clarification can be categorized into:

• Passive Clarification (shōkyokuteki shakumei): Addressing existing unclear, contradictory, or deficient statements from parties. This is generally seen as less intrusive.
• Active Clarification (sekkyokuteki shakumei): More proactively indicating defects in a party's case or suggesting they make certain assertions or present certain evidence. This form is exercised more cautiously to avoid perceptions of judicial bias.

A developing aspect of this duty is the "duty to point out legal viewpoints" (hōteki kanten shiteki gimu). If the court is considering resolving the case based on a legal theory or interpretation different from those argued by the parties, it may be obligated to inform the parties of its perspective. This allows parties an opportunity to address the court's viewpoint and submit further arguments or evidence, thereby preventing surprise judgments (a Supreme Court judgment on October 14, 2010, is often cited as indicating this trend). Shakumeiken thus acts as a crucial supplement to Benron-shugi, aiming to ensure that party autonomy does not lead to a judgment based on an incomplete or misunderstood factual or legal picture.

Practical Implications and Strategic Considerations in the Benron-shugi System

For litigants, especially those from common law backgrounds, Benron-shugi has significant practical implications:

• Meticulous Pleading: The emphasis on party assertion of principal facts means that initial pleadings (the complaint and answer) must be drafted with great care to include all essential factual elements supporting the claim or defense. An oversight can be difficult to rectify later.
• Proactive Evidence Strategy: Since parties are responsible for proffering evidence, a proactive strategy for identifying, securing, and presenting supporting evidence is vital. This includes making timely use of mechanisms like document production orders.
• Responding to Opponent's Assertions: Each factual assertion by the opponent must be carefully reviewed and responded to – either by admission (creating a judicial admission), denial, or by raising an affirmative defense. Ignoring an opponent's factual allegation can lead to a "constructive admission" (gisei jihaku - CCP Art. 159).
• Engagement with the Court's Clarifications: Parties must be prepared to respond thoroughly to the court's questions and prompts under its Shakumeiken. This is an opportunity to refine arguments and ensure the court fully understands the party's position.
• No "Trial by Ambush": While Benron-shugi requires parties to lay their factual cards on the table, the court's active role in clarification and the structured nature of proceedings aim to prevent unfair surprise.

Comparison with the U.S. Adversarial System

While Benron-shugi shares the adversarial spirit of the U.S. system in that parties drive the presentation of their cases, there are key differences:

• Judicial Role in Case Development: Japanese judges, through Shakumeiken, often play a more active role in guiding the clarification of issues and the development of the factual record than their U.S. counterparts might in a purely adversarial model. While U.S. judges have significant case management powers, the nature and extent of direct factual and legal clarification during hearings can differ.
• Pre-trial Discovery: The most significant difference lies in pre-trial discovery. The U.S. system's extensive party-driven discovery (depositions, interrogatories, requests for admission, broad document production) is largely absent in Japan. Evidence gathering in Japan relies more on voluntary disclosure, targeted document production orders from the court, and evidence presented during the main hearing stages. This makes the initial assertions under Benron-shugi and the evidence directly proffered to the court particularly critical.
• Fact Pleading Standards: Although pleading standards are evolving globally, traditionally, Japanese civil procedure has expected a fairly detailed pleading of principal facts directly linked to the elements of the claim or defense, which can be contrasted with the "notice pleading" standard historically prevalent in U.S. federal courts (though standards in the U.S. have also become more demanding following cases like Twombly and Iqbal).

Conclusion

The Principle of Party Presentation, Benron-shugi, is a cornerstone of the Japanese civil litigation landscape. It entrusts litigants with the primary responsibility for defining the factual scope of their dispute and for bringing forward the evidence to support their contentions. This system champions party autonomy but concurrently demands a high degree of diligence, precision in pleading, and strategic evidentiary presentation. The court’s power of clarification, Shakumeiken, serves as an important counterbalance, ensuring that the pursuit of party-driven justice does not compromise the clarity and completeness necessary for a fair and well-informed adjudication. For any U.S. company or legal professional involved in the Japanese legal system, a thorough appreciation of Benron-shugi and its practical ramifications is not just beneficial—it is essential for navigating the process successfully.