Sadamichi Hirasawa

Sadamichi Hirasawa (平沢 貞通, Hirasawa Sadamichi^?, February 18, 1892 – May 10, 1987) was a Japanese tempera painter. He was convicted of mass poisoning and sentenced to death, though he is believed to have been falsely charged. Due to strong suspicions that he was innocent, no justice minister ever signed his death warrant.

On January 26, 1948, a man calling himself an epidemiologist arrived in a branch of the Imperial Bank (Teikoku Ginko, aka Teigin) at Shiinamachi, a suburb of Toshima, Tokyo, before closing time. He explained that he was a public health official sent by US occupation authorities who had orders to inoculate the staff against a sudden outbreak of dysentery. He gave all sixteen people present a pill and a few drops of liquid. Those present drank the liquid he gave, which was later thought to be a cyanide solution. When all were incapacitated, the robber took all the money he could find, which amounted to 160,000 yen (about $2,000 US at the time). Ten of the victims died at the scene (one was a child of an employee) and two others died while hospitalized.

Hirasawa was caught by the police due to the Japanese habit of exchanging business cards with personal details. There had been two other extremely similar cases of attempted and actual theft at banks via the use of poison in the weeks and months prior to the robbery. In all cases the poisoner, a lone male, left a business card. The poisoner used a card which was marked "Jirō Yamaguchi" in one of the two incidents, but it was later found that said Yamaguchi did not exist: the card was a fake. The poisoner also used a real card which was marked "Shigeru Matsui" (of the Ministry of Health and Welfare, Department of Disease Prevention) in another of the two incidents. The original owner of the card was found to have an alibi. Matsui told the police that he had exchanged cards with 593 people, but of these, 100 were of the type used in the poisoning incidents, of which eight remained in his possession. Matsui recorded the time and place of the business card exchange on the back of cards he received so the police set out to trace the remaining 92 cards. 62 cards were retrieved and their receivers cleared, a further 22 were deemed to have been irrelevant to the case. One of the remaining 8 cards was received by Hirasawa. The police were led to arrest Hirasawa because

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