Masumi Hayashi (murderer)

Last updated
Masumi Hayashi
Born (1961-07-22) July 22, 1961 (age 59)
Criminal penalty Death
DateJuly 25, 1998
Location(s) Wakayama Prefecture, Japan
Date apprehended
October 4, 1998

Masumi Hayashi (林 眞須美, Hayashi Masumi, born July 22, 1961) is a Japanese woman convicted of putting poison in a pot of curry being served at a 1998 summer festival in the Sonobe district of Wakayama, Wakayama, Japan.



A communal pot of curry being served to residents of Sonobe district, Wakayama, was poisoned with at least 1,000 grams of arsenic — enough to kill over 100 people — on July 25, 1998.

Two children and two adults died after consuming the curry, and 63 others suffered from acute arsenic poisoning. Killed in the incident were 64-year-old Takatoshi Taninaka and 53-year-old Takaaki Tanaka (council president and vice president of Wakayama, respectively), 10-year-old Hirotaka Hayashi, and 16-year-old Miyuki Torii. [1]

Attention quickly focused on 37-year-old mother of four Masumi Hayashi, as she was seen by a witness at the curry dish, and she had easy access to arsenic because her husband was an insect exterminator. Prior to the murders, Hayashi had been an insurance saleswoman. After her arrest, she and her husband were indicted on a number of insurance fraud charges as well. Hayashi was also tried for three other attempted murders by poison that had occurred during the previous 10 years, with the motive in those cases being life insurance benefits. She is believed to have tried to kill her husband at least once. Her motive for poisoning the curry has been said to be anger at her neighbours for shunning her family. The arsenic found in the curry was identical to the arsenic she had in her own home from her husband's extermination business.


At her trial she pleaded innocent, but Wakayama District Court sentenced her to death in 2002. On June 28, 2005, Osaka High Court upheld her death sentence. However, her lawyers (Yoshihiro Yasuda among them) insisted on her innocence because only circumstantial evidence existed. [2]

On April 21, 2009, the Supreme Court of Japan rejected her final appeal. [3] [4] [ dead link ]

In July 2009, Hayashi formally petitioned for a retrial. [5] Wakayama District Court rejected her petition in March 2017. Hayashi appealed to Osaka High Court by April 2017, [6] [7] but the request was rejected. [8] A third petition for retrial was filed in June 2021. [8]


Hayashi's case gained public attention. The crime inspired a wave of copycat poisonings. [9]

On June 9, 2021, Masumi's 37-year-old daughter jumped off a bridge at Kansai Airport, killing herself and her 4-year-old daughter. [8] Her 16-year-old daughter was found bludgeoned to death earlier the same day. [8]

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  1. "Curry victims' kin sue convicted poisoner". The Japan Times. 2003-03-12. Archived from the original on 2008-10-25. Retrieved 2008-03-23.
  2. "Courts ignore reasonable doubt: lawyers". The Japan Times. 2006-11-16. Archived from the original on 2008-10-25. Retrieved 2008-02-04.
  3. "Death sentence upheld for Wakayama curry killer". Mainichi Shimbun. 2009-04-21. Archived from the original on April 22, 2009. Retrieved 2009-04-21.
  4. "Japanese curry killer loses death sentence appeal". Agence France-Presse. 2009-04-21. Retrieved 2009-04-21.[ dead link ]
  5. "Curry poisoner seeks retrial" Archived 2009-07-27 at the Wayback Machine Kyodo News, "Curry poisoner seeks retrial", Japan Times , July 23, 2009, p. 2.[ dead link ]
  6. "林死刑囚側が即時抗告=毒物カレー再審請求棄却で:時事ドットコム". 時事ドットコム (in Japanese). Retrieved 2017-05-01.
  7. "Poisonous curry no appreciation rejected = Claims death row forest demanded - Wakayama district court" (in Japanese). 29 March 2017. Retrieved 10 June 2017.
  8. 1 2 3 4
  9. "Japan's 'curry killer' sentenced to death". BBC. 2002-12-11. Retrieved 2008-02-04.