Kau Kobayashi was executed on June 11, 1970, in Tokyo. She was 61 and was the first woman executed in postwar Japan. The courts had found her responsible for three deaths in separate events: her husband's in 1952, and in 1960 the wife of the owner of the Nihonkaku inn in Shiobara, Tochigi, and then the owner himself. Her hired accomplice in the two 1960 killings was tried with her and was also executed.
Kau was born in 1908 in Tamai village, in the Osato District of Saitama Prefecture, now part of Kumagaya. She was the fifth of seven children in a poor farming family. She attended elementary school up to the fourth year, then spent about five years helping to raise her younger siblings. At 16 she went to Tokyo as a live-in maid at an inn in Hongo, drawn by a wish to leave the countryside for the city.
In 1930, at 22, she returned home and entered an arranged marriage, made through her sister, to a 27-year-old from Kashiwazaki in Niigata. He was slight and in frail health, and she was unhappy in the marriage. A son born in 1931 died shortly after birth, and a daughter followed in 1932.
The family moved between towns on the edge of Tokyo. During the Pacific War her husband was drafted and came home in poor health. They settled in Kumagaya, where he worked as a tire broker, while Kau sold sweets and pickles door to door. Her earnings kept the household going.
In 1951, at 43, she began a relationship with a police officer 25 years old. She asked her husband for a divorce and he refused. On October 2, 1952, her husband died in Kumagaya. The officer was later tried as her accomplice in the case; his sentence is not on record.
In the spring of 1956 she opened a shop at a hot-spring resort in Tochigi. In 1958 she began a relationship with Kamasuke Ubukata, the owner of the Nihonkaku inn in the Shiobara hot-spring district, and the two agreed to run the inn together. She styled herself its co-operator, and her occupation in the March 1961 indictment was given as inn business.
In February 1960 Ubukata's wife, Ume, was killed. At the end of 1960 Ubukata himself was killed. After that Kobayashi held control of the inn. The courts found that a hired day laborer, Kokichi Onuki, took part in the killings, and that she acted with him. Police at the time believed that her aim was to take over the inn.
On the morning of February 20, 1961, police arrested Onuki, then 37, on suspicion of theft. He confessed, and the warrant against him was changed to one for murder. Later that day Kobayashi, then 52 and the owner of a goods shop in Shiobara, was arrested on suspicion of murder on the strength of his confession. She was held at Utsunomiya police station and Onuki at Otawara police station. At first she did not confess, and the case rested on his statement.
Ubukata was 53 and his wife 48. By March 2, 1961, her husband's death nine years before was strongly suspected to have been a killing. Detectives from the Tochigi prefectural police traveled to Kumagaya, and the Saitama prefectural police and the Kumagaya police worked with them. It became the third killing in the case. She was indicted in March 1961.
In 1961 she was quoted as saying she would not face execution because she was a woman: "I am a woman, so there is no death penalty."
Kobayashi and Onuki were tried together. The Utsunomiya District Court, as the court of first instance, sentenced her to death in 1963, probably in August. A death sentence was handed down to her and Onuki again at the appeal stage. The name of that court, the date of the decision and whether the 1952 death was added to the case at that stage are not on record.
On July 14, 1966, the First Petty Bench of the Supreme Court dismissed her appeal and made the death sentence final. Onuki's sentence was the same.
While held in Tokyo she was said to be calm; she continued to joke with guards in the detention center, and she went to her execution quietly.
Kau Kobayashi was executed on June 11, 1970, at Kosuge in Tokyo, aged 61. She was the first woman executed in postwar Japan. The date is also given as June 10, 1970. Onuki was also executed; his date is not on record.
Convicted: the deaths of her husband in 1952 and of the wife and the owner of the Nihonkaku inn in 1960, by final judgment of the Supreme Court on July 14, 1966.
Date of execution: June 11, 1970, also given as June 10, 1970.
District court date: 1963, probably August. The date of the Tokyo High Court decision is not on record.
1908: Kau is born in Tamai village, Osato District, Saitama.
1930: marries in an arranged marriage.
1951: begins a relationship with a police officer.
October 2, 1952: her husband dies in Kumagaya.
Spring 1956: opens a shop at a hot-spring resort in Tochigi.
1958: begins a relationship with the Nihonkaku inn owner and agrees to run the inn with him.
February 1960: the inn owner's wife is killed.
End of 1960: the inn owner is killed.
February 20, 1961: Onuki and then Kobayashi are arrested.
March 1961: indicted; the 1952 death is now suspected to be a killing.
1963: sentenced to death by the Utsunomiya District Court.
July 14, 1966: the Supreme Court makes the death sentence final.
June 11, 1970: executed in Tokyo.