A Comprehensive Study of the Practical Function and Theoretical Significance of the Empirical Rule in Contemporary Criminal Fact-Finding

2023 Fiscal Year Final Research Report

• Project/Area Number: 18K01317
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 05050:Criminal law-related
• Research Institution: Kyushu University
• Principal Investigator: Toyosaki Nanae 九州大学, 法学研究院, 教授 (50282091)
• Project Period (FY): 2018-04-01 – 2024-03-31
• Keywords: 刑事訴訟法 / 経験則 / 事実認定 / 証拠評価 / 間接事実 / 情況証拠 / 自白 / 鑑定

Outline of Final Research Achievements

This study has shown that the method of determining a defendant's guilt based on indirect facts, such as the defendant's false exculpatory acts, confessional behavior, and the hierarchical relationship between the defendant and the perpetrator in a gang, has evidentiary weaknesses in the double sense that it lacks a multifaceted body of evidence and relies on a naive "rule of thumb" that lacks empirical validity. In addition, the method of affirming the credibility of a confession by a person with poor communication skills or a confession with shifting statements as consistent with other indirect facts, or recognizing the guilt of the accused based on a comprehensive evaluation of such a confession and indirect facts, depends on a simple "rule of thumb": "People do not tell lies that are harmful to themselves ".

Free Research Field

刑事訴訟法

Academic Significance and Societal Importance of the Research Achievements

本研究は、経験則に関する伝統的な学説に対し根本的なパラダイム転換の必要性を説く点で、学界に一石を投じるものである。また本研究は、経験則に大きく依存することによって自白や一定の間接事実を決め手に位置付けても、証拠の脆弱性はカバーできないことを解明し、誤判・冤罪の原因の一端を明らかにしている点で、社会的な意義がある。