This book introduces methods to analyze legal documents such as negotiation records and legal precedents, using computational argumentation theory.First, a method to automatically evaluate argumentation skills from the records of argumentation exercises is proposed. In law school, argumentation exercises are often conducted and many records of them are produced. From each utterance in the record, a pattern of “speech act +factor” is extracted, and argumentation skills are evaluated from the sequences of the patterns, using a scoring prediction model constructed by multiple regression analyses between the appearance pattern and the scoring results. The usefulness of this method is shown by applying it to the example case “the garbage house problem”.
Second, a method of extracting factors (elements that characterize precedents and cases) and legal topoi from individual precedents and using them as the expression of precedents to analyze how the pattern of factors and legal topoi appearing in a group of precedents affects the judgment (plaintiff wins/defendant wins) is proposed. This method has been applied to a group of tax cases.
Third, the logical structure of 70 labor cases is described in detail by using factors and a bipolar argumentation framework (BAF) and an (extended argumentation framework (EAF) together. BAF describes the logical structure between plaintiff and defendant, and EAF describes the decision of the judge. Incorporating the legal topoi into the EAF of computational argumentation theory, the strength of the analysis of precedents by combined use of factored BAF and EAF, not only which argument the judge adopted could be specified.It was also possible to determine what kind of value judgment was made and to verify the logic. The analysis methods in this book demonstrate the application of logic-based AI methods to the legal domain, and they contribute to the education and training of law school students in logical ways of argumentation.
Author(s): Hayato Hirata, Katsumi Nitta
Series: Translational Systems Sciences, 29
Publisher: Springer
Year: 2022
Language: English
Pages: 161
City: Singapore
Preface
Acknowledgments
Contents
About the Authors
Chapter 1: Introduction
1.1 Background and Purpose of the Study
1.2 Structure of This Book
References
Chapter 2: Related Research
2.1 Research on Argumentation Education
2.1.1 The Socratic Method
2.1.2 Case Method
2.1.3 The Problem Method
2.2 Factor-Based Legal Argumentation Support System
2.2.1 Structure of Precedents
2.2.2 HYPO, a Legal Argumentation System Using Precedents
2.2.3 CATO, an Argumentation System Using Case Law
2.3 Related Techniques for Argumentation Evaluation
2.3.1 Toulmin Diagram
2.3.2 Argumentation Protocol
2.4 Legal Topos (Legal Value)
2.4.1 Topoi Catalog
2.4.2 Expanded Topoi Catalog
2.5 Computational Argumentation Theory
2.5.1 Argumentation Framework (AF)
2.5.2 Bipolar Argumentation Framework (BAF)
2.5.3 Extended Argumentation Framework (EAF)
2.6 Factor-Based Argumentation Analysis
2.6.1 Argumentation Analysis by Factors
2.6.2 Argumentation Protocol and Factors
2.6.3 Legal Topoi and Factors
2.6.4 Argumentation Frameworks and Factors
References
Chapter 3: Factor-Based Argumentation Evaluation
3.1 Background and Objectives
3.2 Evaluation Criteria for Argumentations
3.2.1 Scoring Items for Arbitration (Competitive Argumentations)
3.2.2 Scoring Items for Negotiation (Cooperative Argumentations)
3.3 Analysis of Argumentation Skills
3.3.1 Overview of the Analysis
3.3.2 Feature Calculation
3.3.3 Correlation Analysis and Discriminant Analysis
3.4 Example of Argumentation Skill Analysis
3.4.1 Controversial Issue (Garbage House Problem)
3.4.2 Factors of the Garbage House Problem
3.4.3 Argumentation Data and Experts´ Argumentation Evaluation
3.4.4 Tagging
3.4.5 Features in the Garbage House
3.4.6 Correlation Analysis
3.5 Summary
References
Chapter 4: Case Analysis Using Factors and Legal Topoi to Case Law Education
4.1 Background and Objectives
4.2 Overview of Case Law Analysis by Factors and Legal Topoi
4.2.1 Preliminary Preparation (Construction of Hierarchy of Factors)
4.2.2 Preliminary Preparation (Construction of Topoi Hierarchy)
4.2.3 Analysis of Cases by Factors and Legal Topoi
4.3 Examples of Analysis in Tax Law Cases
4.3.1 Tax Law Cases to Be Analyzed
4.3.2 Factors and Legal Topoi of Taxation Issues
§1 Factors of Taxation Issues
§2 Legal Topoi of the Taxation Problem
§3 Relationship Between Factors and Legal Topoi in Taxation Problems
4.3.3 Analysis of Individual Tax Cases
4.3.4 Comparison Between Cases
4.3.5 Conclusion
References
Chapter 5: Case Analysis for Case Law Education Using Factors and Computational Argumentation Theory
5.1 Background and Objectives
5.2 Overview of Case Law Analysis Using Factors and BAF/EAF
5.2.1 Preliminary Preparation (Construction of Hierarchy of Factors)
5.2.2 Analysis of Precedents Using Factors and BAF/EAF
5.3 Examples of Analysis in Labor Cases
5.3.1 Targeted Labor Cases
5.3.2 List of Factors from Labor Court Cases
5.3.3 Importance Analysis of Factors in Labor Court Cases
5.3.4 Issue Analysis by BAF with Factors
5.3.5 EAF Extraction and Logic Verification from Labor Case Studies
5.4 Conclusion
References
Chapter 6: Conclusion
6.1 Summary
6.2 Future Research Topics
