She grew up in Tainan, left vocational school, and worked as a hostess in a bar. She did well at it: good-looking and attentive, one of the more sought-after women in the place, and and she picked up a habit there of betting on the liuhecai lottery. By 2008 the debts were reported at twenty million Taiwan dollars. She later married Liu Yuhang, and the couple ran a business making and selling stinky tofu wholesale in Puli, in Nantou County.
In September 2008 she took out insurance on her mother. About a month later she went back to the family home in Tainan, argued with her about money, and pushed her down the stairs from behind. Hou Yueyun was fifty-three. It was recorded as a fall, and the insurance paid out five million Taiwan dollars.
Then she insured her mother-in-law and her husband for more than fifteen million between them.
In May 2009 she put something in her mother-in-law’s food, and when Zheng Huishen was admitted to hospital she injected the intravenous drip. Zheng was forty-seven. A neurologist at the hospital told the court he had been practicing for more than twenty years and had never heard of anything like it.
A month later she started on her husband. Liu Yuhang was twenty-seven. The first attempt, in June, did not kill him. The second, in July, did: agricultural pesticide and methanol in the drip while he lay in a hospital bed.
Two things ended it. An insurance agent looked at the claim on her husband, held it back and went to the police. And a nurse who had seen her doing something to an intravenous bottle had kept the bottle. It tested positive for poison and it was produced in court.
The deaths had come too close together to survive any scrutiny at all.
At her trial she took back most of what she had told the police. She denied pushing her mother. She denied an arson at a stinky tofu shop the previous August. She admitted poisoning her husband but said it was because he had beaten her, not for the money. The only killing she admitted in full was her mother-in-law’s, for an insurance payment of ten and a half million. She asked to be given a polygraph test to prove she had not killed her mother.
She also said that her husband had given her the poison and told her to put it in his own mother’s drip. She was tested on that statement and she passed. The court declined to accept the result, holding it unreliable. A doctoral study of sixty-two Taiwanese capital cases has since pointed out that in another death penalty case a defendant who failed a polygraph had the failure admitted in evidence.
The prosecution asked for three death sentences. On May 20, 2011 the Nantou district court gave her two life terms and one death sentence. In February 2012 the Taichung branch of the high court reduced the death sentence to life.
The Supreme Court confirmed the two life sentences, holding that the killings of her mother and her mother-in-law met the statutory conditions for voluntary surrender. It sent the count for her husband back for retrial. On September 13, 2012 the Taichung high court reheard it and imposed death. The presiding judge said that for the sake of her own need for money she had disregarded the bond between husband and wife, and that it could not be forgiven.
The Supreme Court dismissed her appeal on June 14, 2013 and the death sentence became final, with lifetime deprivation of civil rights. She was Taiwan’s first woman under sentence of death in twenty-three years, and the fourth in its history. The victims’ relatives set off firecrackers.
Her lawyers had argued that she should not be executed because she is intellectually disabled. She was assessed on the Wechsler Adult Intelligence Scale at an IQ of 57, against a Taiwanese average of about 104, and she has depression. The courts rejected it on the reasoning that a woman who had gambled on the lottery for years and studied the numbers could not be of impaired intelligence.
In 2024 the Constitutional Court heard a challenge brought by thirty-seven prisoners under sentence of death, and on September 20 it issued its judgment. It held the death penalty constitutional but narrowed it sharply, ruling that people with mental disorder or intellectual disability may not be executed, and named her as one of those it applied to. Until the law is amended she cannot be executed; once it is, the Prosecutor-General may bring an extraordinary appeal on her behalf. The victims' relatives said they found it hard to accept. When the state executed Huang Lin-kai in January 2025, thirty-six people remained under sentence of death, and she was the only woman among them.
She was held at Taichung Women's Prison, where officials reported in 2024 and 2025 that she was serving her sentence without incident; they had earlier said her state of mind had long been unstable and that her lawyer was her only visitor.
The Taiwan Alliance to End the Death Penalty, which has written about her at length, adds context the judgments leave out. Her husband was not only a gambler but a bookmaker, and when she owed money he told her to deal with it herself. She was the one insuring the family and nursing her sick mother-in-law, her sick husband and her own mother. The alliance's report on fifteen years of Taiwanese death sentences listed her case among ten with procedural failings, because of the evidence of her intellectual disability.