Stella Nickell is convicted on two counts of murder by a Seattle, Washington, jury. She was the first person to be found guilty of violating the Federal Anti-Tampering Act after putting cyanide in Excedrin capsules in an effort to kill her husband.

Stella and Bruce Nickell married in 1976, shortly after seven people were killed in Chicago, Illinois, from poisoned Tylenol pills. According to Stella’s daughter from a previous marriage, Stella had begun planning Bruce’s murder almost from the honeymoon. The Chicago Tylenol incident (which was never solved) had a lasting impact on Stella, who decided that cyanide would be a good method of murder.

In 1985, Stella took out a life insurance policy on Bruce that included a substantial indemnity payment for accidental death. A year later, Stella put cyanide in an Excedrin capsule that Bruce later took for a headache. He died in the hospital, but doctors did not detect the cyanide and ascribed the death to emphysema. Stella, who stood to lose $100,000 if his death wasn’t ruled an accident, decided to alter her plan.

Nickell tampered with five additional bottles of Excedrin and placed them on store shelves in the Seattle area. Six days later, Susan Snow took one of these capsules and died instantly. After her death was reported in the news, Stella called police to tell them that she thought her husband had also been poisoned.

When investigators came to Nickell’s home to pick up the Excedrin bottle, she told them that there were two bottles and that she had purchased them on different days at different places. When both turned out to contain contaminated capsules, investigators grew suspicious. FBI detectives knew that it was an unlikely coincidence that Nickell had purchased two of four known contaminated bottles purely by chance. Still, hard evidence against her was hard to come by until January 1988.

Cynthia Hamilton, Stella’s daughter, came forward (possibly in order to obtain reward money) with her account of Stella’s plan to kill her husband. She told authorities that her mother had done extensive research at the library. When detectives investigated, they found that Stella had borrowed, but never returned, a book called Human Poisoning. Her fingerprints were also found all over other books on cyanide.

Nickell was given two 90-year sentences for the murders of her husband and Susan Snow.

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