A woman pleaded guilty in an Edmonton courthouse Monday to one count of manslaughter in an overdose death that was later deemed a homicide. Joseph Mercier, 60, was found dead by EMS at a home in the area of 79 Street and 118 Avenue on Dec. 28, 2022. At the time, police did not consider Mercier’s death to be suspicious, saying he died from an overdose following a toxicology report in March 2023 that found his cause of death to be fentanyl toxicity. Following the release of the toxicology report, a witness came forward with information prompting police to reopen the investigation. Morgan Churchill was arrested and charged with second-degree murder on March 26, 2025, in connection to Mercier’s death. On Monday, court heard that Mercier and Churchill were both heavy fentanyl users in 2022. The two were using together at their home on Dec. 22, 2022, when Churchill consensually injected Mercier with about a gram of fentanyl and a gram-and-a-half of cocaine. It is alleged that Mercier told Churchill to “go big or go home.” Mercier fell to the floor immediately. Churchill, who was also intoxicated at the time, dragged his body from the bathroom to the living room to make him more comfortable, court heard, before going to a friend’s home and telling them what had happened. After returning to their home on Dec. 28 after visiting friends over Christmas, Churchill found Mericer’s body in a state of decomposition. She called 911. On March 6, 2023, a witness contacted Edmonton police, prompting them to reopen the case and resulted in a modified ‘Mr. Big’ investigation which began in January 2025. During the undercover investigation, Churchill admitted to injecting Mercier with a large dose of fentanyl and acknowledged that the dose was a significant contributing cause of his death. Justice Steven Mandziuk accepted a joint sentence submission by the Crown and defence, sentencing Churchill to three-and-a-half years less time in custody, leaving her 525 days left to serve. Mandziuk said he took Churchill’s drug addiction and traumatic past into consideration, as well as the remorse she feels indicative of the guilty plea. “This is a terrible tragedy for everybody,” Mandziuk told the court. With files from CTV News Edmonton’s Amanda Anderson
