Tokyo court ruling raises bar on tsunami foresight

Asahi Shimbun

2 days ago

Plaintiffs in a TEPCO-related lawsuit head to the Tokyo High Court in Tokyo's Chiyoda Ward on June 6. (Masaaki Kobayashi)
Two diametrically opposed court rulings have been handed down concerning accountability for the 2011 nuclear disaster. How did this come about?
In 2022, the Tokyo District Court ordered former executives of plant operator Tokyo Electric Power Co. to pay the company about 13 trillion yen ($92.6 billion) in compensation for the accident in Fukushima Prefecture.
But a Tokyo High Court decision on June 6 denied they were liable and rescinded the decision.
The conflicting court decisions are due to differing perceptions of 'duty' required of executives of nuclear power plant operators to safeguard their facilities.
The lower court's ruling found that the TEPCO management proved grossly negligent through its failure to take all possible measures for 'just in case' scenarios.
It noted that a long-term assessment of earthquake forecasts released by the central government in 2002 was made by top-level researchers and, therefore, scientifically reliable.
In the absence of special circumstances, 'tsunami countermeasures based on this knowledge were obligatory,' the court added.
In a 636-page decision, it gave a detailed explanation for holding TEPCO's management responsible.
Based on the 2002 long-term assessment, it said TEPCO could have foreseen a huge tsunami resulting from a massive offshore earthquake and prepared for the event by making the buildings and equipment watertight.
But the high court, in its view of the 'duty,' contended that 'the only way to prevent the accident was to have shut down the nuclear power plant.'
The nuclear power plant business is promoted as a national policy. Ensuring a stable power supply is fundamental to people's lives and economic activity.
Based on this premise, the high court noted that to foresee a tsunami, it is necessary to have 'enough specificity to obligate the suspension of nuclear power plants.'
On the issue of foresight, the high court set the bar extremely high.
It questioned the 2002 long-term assessment, which served as the primary weapon in the plaintiffs' assertion that TEPCO's management could have foreseen the giant tsunami, saying there was no sufficient basis for the claim.
The high court found that the long-term assessment was not sufficiently reliable to have obligated the management at the time to suspend the plant operations.
It also stated the lack of 'a sense of urgency' on the part of the management regarding the long-term assessment was 'unavoidable.'
For this reason, the issue of foresight by the former management was denied by the court.
But why was it raised at the high court?
Two recent decisions by the Supreme Court are believed to have had an influence.
In 2022, the top court ruled in a lawsuit filed by nuclear power plant evacuees seeking compensation from the central government and other parties that 'the earthquake was bigger than expected and that the (nuclear) accident could not have been prevented even if countermeasures had been taken.'
In March of this year, the Supreme Court upheld a high court ruling in a lawsuit in which two former executives were held criminally liable, stating that 'the long-term assessment was not reliable,' and acquitted them of all charges.
The Supreme Court's conclusion--that the earthquake was too big to avoid an accident and the long-term evaluation was unreliable to begin with--was reflected in the high court's latest decision.
The lawsuit was the last remaining avenue for the victims, who contend it is unacceptable that the former management of TEPCO should not be held responsible for the unprecedented accident.
After the ruling, the plaintiffs told their supporters that the decision was 'unjust' and 'needs to be overturned.' They vowed to take the case to the Supreme Court.