Cases on ExcellentWiki - Legal Encyclopedia

The Hateruma Election Case (1993) — Equality of Suffrage

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Hateruma Election Case (Hateruma Senkyo Soshō, Saiko Saibansho, Grand Bench, June 23, 1993) is a landmark Japanese constitutional decision on the principle of equality of suffrage (tōhyō kachi no byōdō) and the permissible limits of malapportionment in elections to the House of Representatives. The case represents the Supreme Court’s most significant intervention in the long-running controversy over the severe disparities in the value of votes between rural and urban electoral districts.

The Itai-Itai Disease Case (1972) — Environmental Tort and Corporate Liability

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Itai-Itai Disease Case (Toyama District Court, June 30, 1971; Nagoya High Court, August 9, 1972) is one of the “Big Four” landmark pollution disease cases that transformed Japanese environmental law and the law of torts in the post-war period. The case — one of the most significant environmental tort decisions in Japanese legal history — established the “probability” standard for proof of causation in pollution cases and demonstrated the courts’ willingness to hold large corporations liable for the environmental and health consequences of their industrial operations.

The Minamata Disease Cases (1973) — Corporate Responsibility for Industrial Pollution

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Minamata Disease Cases (Kumamoto District Court, March 20, 1973; Fukuoka High Court, February 6, 1975; affirmed by the Supreme Court, December 13, 1976) represent one of the most significant environmental tort litigations in Japanese and global legal history. The cases arose from the discharge of methylmercury by the Chisso Corporation into Minamata Bay, Kumamoto Prefecture, which caused severe neurological damage — Minamata disease — to thousands of residents of the coastal community.

The Mitsubishi Jushi Case (1973) — Horizontal Application of Constitutional Rights

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Mitsubishi Jushi Case (Mitsubishi Heavy Industries Case, Saiko Saibansho, Grand Bench, December 12, 1973) is the leading Japanese authority on the horizontal application (indirect effect) of constitutional rights to relationships between private parties. The case addressed the extent to which the constitutional guarantees of freedom of expression, thought, and conscience constrain the exercise of private power — specifically, an employer’s right to dismiss an employee.

The Grand Bench’s decision established the doctrinal framework through which constitutional values are mediated into private law via the general clauses of the Civil Code, particularly Article 90 (public order and good morals) and Article 1(3) (abuse of rights). The case has influenced virtually every subsequent Japanese decision involving the interaction between constitutional rights and private law.

The Nagayama Case (1983) — Standards for the Death Penalty in Japan

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Nagayama Case (Saiko Saibansho, Grand Bench, July 8, 1983) is the Supreme Court of Japan’s most important judgment on the standards for imposing the death penalty. The case established the “Nagayama Criteria” — a nine-factor framework that Japanese courts apply when determining whether a capital sentence is appropriate. The judgment represents the Supreme Court’s most comprehensive statement on the relationship between retribution, deterrence, and rehabilitation in capital sentencing.

The Open Housing Cases (1995) — Discrimination and the Right to Housing

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Open Housing Cases (Ōpun Hājingu Jiken) — a series of decisions culminating in the Osaka High Court judgment of July 11, 1995 — represent the most significant Japanese judicial pronouncement on discrimination against Burakumin (members of the historically discriminated community) and on the legal regulation of discriminatory housing practices. The cases addressed the practice of providing information about Burakumin neighbourhoods to real estate companies, enabling discrimination in housing sales and leases.

The Saiban-in (Lay Judge) System — Fundamental Case Law

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Saiban-in Seido (Lay Judge System) is Japan’s system of citizen participation in criminal justice, introduced by the Act on Participation of Lay Judges in Criminal Trials (Saiban-in no Sankasuru Keiji Saiban ni Kansuru Hōritsu) in 2004 and implemented in 2009. The system represents a fundamental reform of Japanese criminal procedure, replacing the pre-war jury system that had fallen into disuse and introducing a new model of mixed lay-professional adjudication.

The Sunagawa Case (1959) — US-Japan Security Treaty and the Political Question Doctrine

Tue, 07 Jul 2026 00:00:00 +0000

Introduction

The Sunagawa Case (Saiko Saibansho, Grand Bench, December 16, 1959) is the foundational Japanese authority on the political question doctrine and the justiciability of treaties under the Constitution of Japan. The case arose from protests against the expansion of the United States military airfield at Sunagawa, a town in what is now part of Tachikawa, Tokyo, and resulted in a landmark judgment that has shaped the Japanese Supreme Court’s approach to national security and foreign relations for over six decades.