An Japanese legal panel recommended indicting three former executives of the utility that runs the Fukushima nuclear power plant that was crippled by a tsunami in 2011.
The independent, 11-member panel ruled Thursday in favor of bringing charges against the former chairman and two ex-vice presidents of the Tokyo Electric Power Company.
Prosecutors decided last year not to charge the TEPCO executives, saying the degree of devastation caused by the 9.0-magnitude earthquake and tsunami was unpredictable.
The Thursday ruling means prosecutors will have to reconsider that decision. If they still refuse to indict the TEPCO officials, the panel could force the case to go to court.
The appeal represented nearly 6,000 residents and activists from Fukushima and elsewhere, who argued that TEPCO ignored the possible threats posed by a tsunami.
A Japanese parliamentary report in 2012 said the disaster was "man-made" and alleged that its direct causes were foreseeable. It faulted both TEPCO and the government.
A massive earthquake and tsunami in March 2011 shut off the plant's power and cooling systems, causing a meltdown in three nuclear reactors. It was the world's worst nuclear disaster since the 1986 Chernobyl accident in the Soviet Union.
Since the disaster, TEPCO has come under criticism for its alleged incompetence.
Over three years later, the plant is still spewing radiation into the atmosphere. Engineers said it will take at least four decades to dismantle the facility.