Who Needs to Prove What in a Japanese Court? The Principle of Party Presentation (Benron Shugi) and Fact-Finding

Japanese Attorney at Law - Bengoshi L.L.

• 8 min read

A fundamental characteristic of civil litigation in Japan is the "Principle of Party Presentation," or Benron Shugi (弁論主義). This doctrine dictates that the responsibility for introducing the factual and evidentiary material necessary for a court's decision rests primarily with the litigating parties, not the court. Understanding Benron Shugi is crucial for anyone involved in Japanese civil proceedings, as it profoundly shapes how cases are pleaded, evidence is presented, and ultimately, how facts are determined by the court. It represents a procedural philosophy distinct from more inquisitorial systems where judges might take a more active role in fact-finding from the outset.

The Three Core Tenets of Benron Shugi

Benron Shugi is generally understood to encompass three core propositions, or "theses," that guide the conduct of civil litigation:

  1. The Court Cannot Base Its Judgment on Facts Not Alleged by the Parties: This is perhaps the most critical aspect. A Japanese court, in rendering its decision, is confined to the factual assertions (allegations) made by the plaintiff and the defendant. Even if evidence presented during the proceedings suggests the existence of a fact that could be decisive, if neither party has formally alleged that fact as part of their claim or defense, the court cannot independently rely on it. This underscores the paramount importance of meticulous pleading and the comprehensive articulation of all relevant facts by the parties themselves. Associated with this is the concept of the "burden of allegation" (shuchō sekinin), which generally falls on the party who stands to benefit from a particular legal rule if the facts satisfying its conditions are established.
  2. Facts Admitted by the Opposing Party, or Not Disputed, Bind the Court: If a party makes a factual allegation and the opposing party explicitly admits it, or fails to clearly dispute it in their responsive pleadings or during oral arguments, that fact is considered a "judicial admission" (saiban-jō no jihaku). Such admitted facts are binding on the court; they must be taken as true without the need for further proof (Article 179, Code of Civil Procedure). This principle streamlines proceedings by narrowing the scope of disputed facts requiring evidentiary proof. However, it's important to distinguish factual admissions from "admissions of rights" (kenri jihaku), such as an admission of the existence of a legal right itself (e.g., "I admit I owe the debt"). Admissions of pure legal conclusions or rights are generally not binding on the court, as the application and interpretation of law are the court's domain.
  3. The Court Generally Does Not Initiate Evidence Gathering Ex Officio for Principal Facts: Flowing from the principle that parties control the factual input, the responsibility for proffering evidence to prove disputed factual allegations also lies with the parties. The court generally does not have the power to independently search for or introduce evidence concerning the "principal facts" of the case, although it does have a role in formally examining the evidence presented by the parties.

The Crucial Distinction: Principal Facts vs. Indirect Facts

The application of Benron Shugi, particularly its first thesis, is primarily focused on what are termed "principal facts" (shuyō jijitsu). Understanding this distinction is vital:

  • Principal Facts (shuyō jijitsu): These are facts that directly correspond to the elements of a substantive legal rule, the establishment of which leads to the recognition of a legal right or effect (e.g., the conclusion of a contract, the occurrence of a negligent act causing damage, the payment of a debt). These are the ultimate facts that a party must allege and prove to succeed on a claim or defense. The burden of allegation and the burden of proof directly pertain to these principal facts.
  • Indirect Facts (kansetsu jijitsu): These are evidentiary facts from which the existence or non-existence of principal facts can be inferred, often through common sense, experience, or logical reasoning. For example, in a loan dispute where the principal fact is the "transfer of money," an indirect fact might be "the debtor suddenly came into a large sum of money around the time of the alleged loan." The court has more leeway with indirect facts; it can often consider them even if not explicitly emphasized by a party, provided they emerge from the properly submitted evidence. Benron Shugi does not apply to indirect facts with the same rigor as it does to principal facts.
  • Auxiliary Facts (hojo jijitsu): These are facts that bear upon the credibility or probative value of a piece of evidence (e.g., a witness's bias, the authenticity of a document's signature). Benron Shugi is also generally not considered to apply strictly to auxiliary facts.

The classification of a fact as "principal" versus "indirect" is a key analytical step. One common way to distinguish them is by considering whether an allegation constitutes an "affirmative defense" (kōben) or an "affirmative denial" (sekkyokuteki hinin).

  • An affirmative defense typically introduces new principal facts that, even if the opponent's principal facts are true, would nevertheless defeat the opponent's claim (e.g., alleging payment in response to a claim for a debt). These new facts are principal facts.
  • An affirmative denial involves alleging facts that are logically inconsistent with the principal facts alleged by the opponent, thereby supporting the denial of those principal facts (e.g., in response to a claim based on a loan, alleging the money was a gift). The facts alleged in an affirmative denial are often considered indirect facts that help the court infer the non-existence of the opponent's principal facts.

For instance, in a dispute over land ownership based on inheritance, the Supreme Court of Japan, in its decision of February 7, 1980 (Minshu Vol. 34, No. 2, p. 123), indicated that a plaintiff claiming ownership through inheritance must allege and prove (1) that their predecessor in title (the deceased) had acquired ownership of the property, and (2) that the plaintiff inherited the estate from the deceased. Facts suggesting that the predecessor subsequently lost ownership before death, or made a specific disposition of the property excluding it from the inheritance, would typically constitute affirmative defenses (new principal facts) for the opposing party to allege and prove.

The Court's Role in Clarification: Shakumeiken and Shakumei Gimu

While Benron Shugi places the primary responsibility for factual and evidentiary presentation on the parties, it is not an entirely passive system from the court's perspective. The Code of Civil Procedure (Article 149) grants the presiding judge the power to ask questions of the parties and to encourage them to present necessary allegations or proof on both factual and legal matters to clarify the litigation relationship (shakumeiken - power to clarify).

This power serves as a crucial corrective mechanism. It aims to prevent meritorious claims from failing, or unmeritorious claims from succeeding, merely due to a party's oversight, lack of legal sophistication (especially in cases involving unrepresented litigants), or an attorney's inadvertent error. The court can exercise this power to:

  • Clarify ambiguous or unclear statements.
  • Point out inconsistencies in a party's allegations.
  • Suggest that a party might need to allege additional facts or submit further evidence to support their position.
  • Explore potential legal arguments that the parties may have overlooked.

This power to clarify can be categorized as:

  • Passive Clarification: Asking questions to understand or make sense of the parties' existing submissions.
  • Active Clarification: More proactively prompting parties to supplement their allegations or evidence, or to consider alternative legal constructions. The Supreme Court, for example, in a decision on June 11, 1970 (Minshu Vol. 24, No. 6, p. 516), upheld a lower court's active clarification that led to a party changing the legal basis of their claim.

In certain situations, this power to clarify transforms into a "duty to clarify" (shakumei gimu). Although not explicitly stipulated as a "duty" in the Code in all instances, case law has established that a failure to exercise the power to clarify can constitute a reversible error if it leads to an unjust outcome. This duty is more likely to arise when:

  • The court perceives that clarification could likely alter the outcome of the case.
  • A party has presented sufficient factual material, but their legal framing is deficient.
  • A party, due to lack of knowledge or resources, is demonstrably unable to make an essential allegation or present crucial proof without prompting.
  • Fairness between the parties requires the court's intervention to ensure a balanced opportunity to present their case.

The Supreme Court has, on several occasions, found a breach of this duty. For example, if a plaintiff claims damages for a wide area but only proves entitlement for a part of it, the court may have a duty to prompt the party to specify and prove damages for that particular part if it appears the party could do so (Supreme Court, June 26, 1964, Minshu Vol. 18, No. 5, p. 954). More recently, the Supreme Court decision of October 14, 2010 (Hanrei Jiho No. 2098, p. 55) emphasized the court's duty to clarify legal perspectives, indicating that if the court is considering a legal basis not fully addressed by the parties, it should give them an opportunity to make submissions on that point to avoid surprise.

Benron Shugi and "General Clauses" (Ippan Jōkō)

A particularly complex area is the application of Benron Shugi to legal requirements expressed as "general clauses" (ippan jōkō). These are broadly phrased legal concepts such as "public order and morals" (Article 90 of the Civil Code), "good faith" (Article 1(2) of the Civil Code), "abuse of rights" (Article 1(3) of the Civil Code), or "negligence" (as in tort law, Article 709 of the Civil Code).

The question is: what constitutes the "principal fact" when such a general clause is at issue? Is it the abstract legal concept itself (e.g., "the defendant was negligent"), or is it the specific, concrete facts that lead the court to such a legal evaluation (e.g., "the defendant was driving at 80 km/h in a 40 km/h zone while using a mobile phone")?

The traditional view considered the general clause itself (e.g., "negligence") as the principal fact. However, the prevailing contemporary view, and one that aligns more closely with the need for specific factual contentions, is that the concrete, underlying facts that form the basis for the legal evaluation are the principal facts. Parties must allege these specific, evaluative facts. Simply asserting "negligence" without detailing the conduct deemed negligent would generally be insufficient.

However, for general clauses with a strong public interest component, such as "public order and morals," the court's role may be somewhat more active. The Supreme Court, in its decision of April 27, 1961 (Minshu Vol. 15, No. 4, p. 901), suggested that if facts amounting to a violation of public order and morals are presented in the proceedings, the court can consider the invalidity of a contract on this ground even if a party has not explicitly argued "invalidity due to violation of Article 90". This implies that if the underlying concrete facts are before the court, it may raise the legal consequence ex officio due to the strong public interest involved, though it would typically clarify this legal viewpoint with the parties.

Interplay with Free Evaluation of Evidence (Jiyū Shinshō Shugi)

While Benron Shugi governs the presentation of factual material and evidence, the evaluation of that evidence, once properly introduced, is subject to the "Principle of Free Evaluation of Evidence" (jiyū shinshō shugi) (Article 247, Code of Civil Procedure). This means the judge is not bound by formal rules of proof but determines the probative value of evidence based on their own conscience and rational judgment, derived from the entirety of the oral arguments and the results of the evidence examination.

Thus, there is a dynamic interplay: parties allege principal facts and offer evidence; the court then freely evaluates this evidence to determine whether the alleged principal facts (those disputed) have been proven to the requisite standard (typically, a high degree of probability).

Practical Implications

For those accustomed to common law systems, particularly the United States with its extensive pre-trial discovery, broad notice pleading, and more active judicial case management in some respects, Benron Shugi presents some key differences:

  • Pleading Precision is Paramount: The complaint and answer are not mere notices. They must meticulously set out all principal facts relied upon. Omissions can be detrimental.
  • Limited Pre-Trial Discovery: Japan does not have a broad, party-driven discovery process akin to that in the U.S. Fact-gathering largely occurs before filing or through more limited, court-supervised procedures during the litigation. Benron Shugi reflects this party-driven, but court-presented, development of the factual record.
  • Admissions are Critical: The binding nature of judicial admissions means that responses to pleadings must be carefully crafted to avoid unintended admissions.
  • The Judge as a Clarifier, Not an Investigator: While the court can clarify, it generally won't step in to make a party's case for them if essential principal facts are missing from the allegations.

Conclusion

The Principle of Party Presentation (Benron Shugi) is a defining feature of the Japanese civil litigation landscape. It places the onus squarely on the litigants to shape the factual contours of their dispute through their allegations and to support those allegations with proffered evidence. While the court's power and, at times, duty to clarify provide a safeguard against manifest injustice arising from procedural missteps, the fundamental responsibility for constructing the factual narrative remains with the parties. A thorough understanding of Benron Shugi, particularly the critical distinction between principal and indirect facts and the binding nature of admissions, is indispensable for effectively navigating civil proceedings in Japan and for developing a sound litigation strategy.