In 1977, the government adopted strict criteria for the official recognition of people as victims of Minamata disease, Japan's worst pollution-induced affliction caused by Chisso Corp. Only someone suffering from a combination of methyl mercury-poisoning symptoms, such as sensory disturbances and visual field constriction, could be recognized as a victim. But on July 16, the Osaka District Court ruled that the criteria lacked medical legitimacy and ordered the Kumamoto Prefectural Government to officially recognize an 84-year-old woman as a Minamata disease victim. The ruling has been appealed.

The government has just started a new relief measure for unrecognized Minamata disease victims, featuring a lump-sum payment of ¥2.1 million and a monthly medical allowance of ¥12,900 to ¥17,700. But the ruling may encourage others to file similar lawsuits since an officially recognized victim qualifies for a lump-sum payment of ¥16 million to ¥18 million and other benefits. But there will be no guarantee that plaintiffs will win in court.

In October 2004, the Supreme Court ruled that a person with only one symptom of the disease should also be recognized as a Minamata victim if certain conditions — such as the official recognition of a family member as a victim — are met. Thus, it awarded ¥4.5 million to ¥8.5 million in compensation to the woman and 36 other people.

Despite this ruling, a state inquiry panel in March 2007 refused to officially recognize her as a victim. She filed a new lawsuit in May 2007. The July 16 ruling said that numbness in the limbs is sufficient to officially recognize a person as a Minamata disease victim if the person was exposed to methyl mercury for a certain period of time, if the numbness is peculiar to Minamata disease and if other causes are unlikely. It is the first ruling to order official recognition of a person as a victim under the revised Administrative Litigation Law.

The state must recognize that only a full revision of its 1977 criteria can realize a true solution to the Minamata disease issue. At the very least, it must conduct comprehensive health checks of residents in the areas polluted by Chisso's waste water.