An 87-year-old man jailed 40 years ago for poisoning five women, including his wife and his mistress, has lost his final appeal in Japan.
A Japanese man who poisoned his wife, lover and three other women with pesticide-laced wine has lost his final bid for a retrial after more than 40 years on death row, a court spokeswoman says.
The supreme court decision, which came down on Wednesday, means that 87-year-old Masaru Okunishi has exhausted all avenues of appeal and will likely die in prison - by old age or execution.
The octogenarian, who spent decades in solitary confinement and is now hospitalised, has long protested his innocence, saying his confession in the 1961 killings was coerced by police.
Okunishi was charged in the deaths of five women who drank wine laced with pesticides at a community party in the remote mountain village of Nabari in central Japan.
The farmer initially told police he added lethal chemicals to the wine to murder both his wife and mistress so he could end a complicated love triangle. A dozen others fell ill but survived.
Okunishi later withdrew the confession and was acquitted in a 1964 trial, with the court citing a lack of evidence.
The decision was overturned by a higher court which sentenced Okunishi to death in 1969.
In the latest appeal, his seventh bid to win a re-trial, Okunishi's defence argued that pesticide used by the convicted killer was not the kind found in the tainted wine.
Japan's highest court ruled that the evidence was not enough to overturn previous rulings, but some rights groups have called for a re-trial over the possibility his confession was coerced.
Okunishi is one of the longest-serving death-row inmates in Japan, where condemned inmates can wait years or even decades in solitary confinement before being executed.
Prisoners are usually told of their impending hanging just hours before it's carried out, which critics denounce as cruel.
Apart from the United States, Japan is the only major industrialised democracy to carry out capital punishment, a practice that has led to repeated protests from European governments and human rights groups.