A Minnesota man has been charged with murder after his roommate died from poisoning, allegedly caused by the toxic heavy metal thallium. Stuart Hanmer, 35, was arrested on Wednesday following an investigation into the death of his roommate, Cody Ernst, 33, who passed away on June 22.
The Mysterious Symptoms and Fatal Outcome
Ernst had been living at a sober facility with Hanmer since May. Shortly after Hanmer arrived, Ernst began experiencing severe symptoms, including vomiting and seizure-like activity, which sent him to the hospital multiple times.
By the time of his death, Ernst was reportedly paralyzed and placed on life support. His former fiancée, Cat Williams, described the way he died as “the most horrific, awful way anybody could pass.”
Discovery of Lethal Poisoning
When Ernst arrived at the University of Minnesota Medical Center on June 20, doctors discovered “an extremely high and lethal level” of thallium in his system.
Thallium, once used as a rodent poison and insecticide, was banned in the U.S. decades ago but is still used in certain industries. The substance’s presence led authorities to investigate further.
Hanmer’s Suspicious Online Searches and Purchases
Investigators found that Hanmer had conducted multiple Google searches related to thallium, including questions about its toxicity and how to purchase it.
According to the criminal complaint, Hanmer made several online transactions totaling $162.56 for 25 grams of thallium metal, which he signed for on May 14—just days before Ernst’s first hospitalization.
Further investigation revealed that Hanmer had watched a YouTube video about creating thallium sulfate and continued researching the substance leading up to Ernst’s death.
Hanmer’s Denial and Arrest
When questioned by police in July, Hanmer denied any knowledge of thallium poisoning before Ernst’s death. He told investigators that he and Ernst had simply smoked marijuana and drank coffee together. However, the evidence against him mounted, and Hanmer was arrested on charges of second-degree intentional murder.
