The latest court ruling on a legal case concerning the government’s relief program for Minamata disease patients challenges the fundamental integrity of the relief system and unequivocally underscores its inadequacy.

The government should accept the verdict and take it as an opportunity to change its policy stance toward the issue to provide relief to all plaintiffs of such cases.

In ruling on the group lawsuit, the Osaka District Court on Sept. 27 ordered the central and Kumamoto prefectural governments, along with Chisso Corp., the chemical company at the center of the environmental catastrophe, to collectively pay compensation to all the plaintiffs of the case.

The suit involves 128 plaintiffs between the ages of 50 and 90 living in Osaka Prefecture and surrounding areas who argued they are suffering symptoms such as limb numbness because they ate seafood contaminated with methylmercury when they lived in Kumamoto and Kagoshima prefectures.

The plaintiffs were not covered by a 2009 special measures law that provided relief to Minamata disease victims for a “political settlement,” or were unable to apply for the program during the application period.

Unlike acute Minamata disease patients who typically suffer intense convulsions due to mercury poisoning, their symptoms are not easily recognizable at a glance.

The ruling placed importance on facts concerning how the plaintiffs consumed a lot of seafood contaminated with methylmercury in their early childhoods.

The special law narrowed the relief targets through requirements including having lived in specific areas along the coast of the Sea of Shiranui that extend between Kumamoto and Kagoshima prefectures for at least a year until 1968 when Chisso stopped discharging wastewater into the sea.

Thousands of people suffered brain damage, numbness, tremors, loss of sight or hearing, or other injuries after eating seafood contaminated with methylmercury included in the wastewater.

The court rejected such geographical and chronological restrictions on the eligibility for the relief program and clearly argued that the actual conditions leading to the onset of the disease cannot be defined simply by proximity or time.

Numerous lawsuits have been initiated concerning Minamata disease. Since the Kumamoto District Court first acknowledged Chisso's responsibility for the disaster in 1973, a series of rulings in favor of plaintiffs have widened the scope of relief for victims.

A landmark ruling in 2004 from the Supreme Court confirmed the responsibilities of the national and prefectural governments and led to the easing of the standards for the official designation as Minamata disease patients.

However, it's difficult for the government to claim it has fully embraced the judiciary’s messages.

Even when the Supreme Court indicated for the second time lenient recognition criteria in 2013, the government didn't alter its designation standards requiring a combination of multiple symptoms.

Instead, the government even released new guidelines raising the bar for official recognition the following year. Such insincere responses should never be repeated.

Group lawsuits have also been filed with the Kumamoto, Niigata and Tokyo district courts, with the total number of plaintiffs exceeding 1,700.

Many of them are advanced in age, pleading for swift relief. The government should launch the process of providing relief for all the plaintiffs without waiting for the decisions by these district courts.

The process should start with a swift health survey of the people claiming to be suffering symptoms linked to the disease. Despite being mandated by the special law, the development of the survey method has taken a long time and how the method should be utilized will be studied over the next three years, according to the government.

The government deserves to be criticized for gross negligence.

Minamata disease was the first whose cause was recognized as industrial pollution in postwar Japan. But the entire picture remains not fully understood even 67 years after it was first identified in 1956.

The special law proclaims to offer relief “as much as possible.” The government must not forget this promise.

--The Asahi Shimbun, Sept. 28