The Supreme Court on Thursday upheld the death sentence of Kieko Ishikawa, a 49-year-old woman convicted of killing and robbing two women in the late 1990s, dismissing her appeal.
In handing down its ruling, presiding Justice Tatsuo Kainaka of the top court's No. 1 petty bench said: "The consequences of killing two people over a relatively short period of time are grave.
"The death sentence is inevitable because the victims had no fault of their own and the crimes were extremely savage and cold blooded."
Her defense counsel had argued that the defendant, an unemployed resident of the city of Miyazaki, cannot be held responsible because she was suffering from schizophrenia and mentally incompetent when the crimes were committed.
Ishikawa's lawyer also claimed a male acquaintance, who has since died, killed one of the victims.
The Supreme Court upheld a lower court finding that Ishikawa was mentally competent at the time of the murders.
In March 2003, the Miyazaki Branch of the Fukuoka High Court ruled Ishikawa used a rope to strangle hotel worker Shizuko Hino, 55, inside a car in the city of Saito, taking about 9,500 yen in cash and a set of golf clubs from the victim in August 1996.
The court also found Ishikawa guilty of choking her friend, Yoko Furuso, 63, to death at the defendant's home in the city of Miyazaki and taking 2 million yen from the victim's bank account in June 1997.
According to the high court ruling, Ishikawa killed Hino because her family, which ran a carpentry workshop, was experiencing financial difficulties, and that she killed Furuso because she refused to lend money to Ishikawa.