The Supreme Court on Friday held the state responsible for the spread of Minamata disease after January 1960.
The ruling brought to a close the only Minamata disease-related lawsuit that had sought to establish government responsibility over the outbreak of the mercury-poisoning disease.
It marked the first judgment by the top court on government responsibility in preventing the outbreak and spread of the disease, which killed hundreds of people, disabled thousands and produced birth defects in Minamata, Kumamoto Prefecture, and surrounding areas.
The disease first came to public attention in May 1956 and went on to become one of the worst pollution-related illnesses to afflict Japan.
Although several compensation lawsuits had been filed over Minamata disease, this was the only one still in the courts after a 1995 government-mediated settlement, which did not address the issue of whether the state and prefecture were responsible for the fiasco.
Presiding Justice Hiroharu Kitagawa of the No. 2 Petty Bench said the central and prefectural governments failed to exercise their regulatory authority in line with water quality laws, and as a result exacerbated the extent of the poisoning to people who ate fish and shellfish caught in the contaminated waters.
In the lawsuit, 30 people who have not been officially recognized as Minamata disease patients and the bereaved families of 15 patients had demanded a total of 1.9 billion yen in compensation from the central and Kumamoto Prefectural governments.
All had moved to the Kansai region from Kumamoto and neighboring Kagoshima Prefecture.
Friday’s Supreme Court ruling obliges the central government and Kumamoto Prefecture to pay a total of some 71.5 million yen to 37 people who fell prey to the disease since January 1960.
It rejected the demands of eight plaintiffs who had moved out of the area before that time.
In its April 2001 ruling, the Osaka High Court ordered the two parties and chemical firm Chisso Corp., which discharged the mercury-laden water from its synthetic resin factory into Minamata Bay, to jointly pay 320 million yen to the plaintiffs.
Tokyo-based Chisso, which was ordered to pay at least 75 percent of the total, did not appeal the high court ruling. The amount of compensation it will pay to the eight plaintiffs who were not recognized by the Supreme Court will not change.
In explaining the reasons behind the court’s decision, Justice Kitagawa said that as of the end of November 1959, the defendants would have known that there were scores of Minamata disease sufferers and that many of them had died.
He also noted that the central government and Kumamoto Prefecture could have determined that some form of organic mercury compound was to blame and that the source of the contamination was Chisso’s Minamata plant, and that they could have measured the amount of mercury in the plant’s waste water.
It was very irrational and illegal for the central government and Kumamoto Prefecture, based on existing laws and regulations at the time, to not clamp restrictions on the waste water after January 1960, he concluded.
The Supreme Court did not provide its own judgment as to what symptoms would qualify a person as a Minamata disease sufferer.
However, it said that “the judgment of the high court is acceptable,” rejecting the central and prefectural governments’ criticism of the high court’s use of different criteria than that of the state to recognize patients.
The ruling also countered the claim made by the governments during a hearing in July that the substances causing the disease were unknown at the time and that the government measures were not illegal.
The plaintiffs had argued that the governments should have banned consumption of local fish and shellfish under the Food Sanitation Law, given that the Minamata Bay marine life was toxic from the mercury.
In an afternoon news conference, Chief Cabinet Secretary Hiroyuki Hosoda said the government will “seriously take to heart” the ruling and vowed to prevent the recurrence of such a tragic case of environmental pollution.
He said he feels sorry for the plaintiffs and their families for their years of hardship.
“It is important (to pursue) the steady implementation of a comprehensive medical program” to address Minamata disease, he said.
In July 1994, the Osaka District Court only ordered Chisso to pay about 280 million yen in damages and cleared the central and prefectural governments of liability. The suit had been filed with the district court in October 1982.
All but one of the suits relating to Minamata disease were withdrawn after the government endorsed in December 1995 the settlement calling on Chisso to provide a lump sump payment of 2.6 million yen each to those not officially recognized as Minamata disease patients.
But the plaintiffs in the lawsuit that concluded Friday refused to accept the government’s decision, seeking to establish the governments’ responsibility for their ordeal.
In April 2001, the Osaka High Court said the central and prefectural governments were responsible and ordered them to pay damages as well.
Takeo Matsumoto, chief lawyer for the plaintiffs, told a news conference: “Had the governments acted properly, the damage (from Minamata disease) would have been been much less than it was. It was correct for (the plaintiffs) to reject a political settlement and pursue the legal battle.”
Minamata disease paralyzes the central nervous system and causes birth defects. Its symptoms include numbness, persistent headaches and impaired balance. It was recognized as a pollution-related disease in September 1968.