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The Significance of Sufferers of Minamata Disease Winning in the Japanese
Supreme Court against the National and Prefectural Governments

Transcript of statement made on April 25, 2006 at the Japan Foreign Correspondents' Club press conference (Japan's Worst Pollution Disaster - MINAMATA DISEASE).

Mari Susa, Associate Professor of Law, Kumamoto University

Let me start by asking you a true/false question. Please read the following definition of Minamata Disease given in the third edition of the Oxford Concise Medical Dictionary (2002):

"Minamata disease --a form of mercury poisoning (from ingesting methyl mercury in contaminated fish) that caused 43 deaths in the Japanese coastal town of Minamata during 1953-56. The source of mercury was traced to an effluent containing mercuric sulphate from a local PVC factory. Symptoms include numbness, difficulty in controlling the limbs, and impaired speech and hearing."

Is this passage true or false? After Aileen Smith and Katsuya Kosaka's explanation, I assume that many of you would say the statement is not true. My intention here is not to blame the Oxford Medical Dictionary. Rather, I wanted to show you that simple facts about Minamata disease are still not well-understood. What caused this misunderstanding, then? One of the major reasons could be that the imperfect understanding of science in Japan concerning Minamata disease might have led people in other countries to have a feeling that Japanese studies were untrustworthy.

Although a definition of Minamata disease is primarily a medical one, under the Law concerning Compensation and Prevention of Pollution-related Health Damage, it has been a legal term as well.

The term "Minamata disease" and "methylmercury poisoning" are used in different contexts by the government. Minamata disease is, certainly, a form of methylmercury poisoning. However, to date, to be legally a Minamata disease patient, sufferers must be officially identified as having Minamata disease according to the Diagnostic Guideline for Minamata disease set forth by the national government in 1977. There have been thousands of people who were not certified under this certification scheme. The plaintiffs who filed the so-called Kansai Lawsuit were among them.

The Supreme Court ruling in the Kansai Lawsuit (October 15, 2002) is significant in that it states the definition of Minamata disease. The ruling, differing from what the Diagnositc Guidelines of Minamata disease set forth by the government in 1977 say, states clearly that the brain is the critical organ in Minamata disease.

In the Osaka High Court ruling, plaintiffs were recognized as methylmercury poisoning cases, hence they were entitled to compensation by the national and prefectural governments. It is noteworthy that the Supreme Court, when it upheld the Osaka High Court ruling, reworded the phrase "methylmercury poisoning cases" to "Minamata disease cases." This should now mean that the Kansai Lawsuit plaintiffs who are not Minamata disease cases according to the government's Diagnostic Guidelines are now proclaimed as Minamata disease cases in the legal context.

The Supreme Court ruling was a landmark ruling in that it established the legal responsibility of government authorities by bringing scientific testimony into the court of law. This ruling in the highest court of the judiciary is an exhortation to the other branches of government, the administrative and legislative, for having failed to properly give relief to the suffers of Minamata disease and thus alleviate this protracted case.


(Adaptations to the text were made for this printed version.)

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