Legal battle over disabled son preceded Mercer Island, WA, murder-suicide
Court docs shed light on legal drama surrounding Mercer Island murder-suicide investigation
Court documents now painting a clearer picture about the family legal battle that surrounded four people killed in two cities that were just miles apart. A mom and her son were found dead at a home on Mercer Island on Tuesday, according to Mercer Island Police. That same day, two others were also found dead at an Issaquah house.
MERCER ISLAND, Wash. - Court records show a heated guardianship battle over a disabled son preceded the deaths of four family members in two cities just miles apart.
(FOX 13 Seattle)
On Tuesday, police found a mother and her son dead inside a Mercer Island home. That same day, two others were found dead at a house in Issaquah.
FOX 13 obtained court documents that shed light on the relationship between 80-year-old Danielle Cuvillier and her 45-year-old son, Mack Williams, in the year before they were both found dead on Mercer Island.
What we don't know:
According to police, their deaths are being investigated as a murder-suicide. The investigation into who pulled the trigger before turning the gun on themselves remains ongoing.
The backstory:
According to court records, Cuvillier and Williams were in a disagreement over the case of Cuvillier's other son Dominick, who is also known as Nick, with each blaming the other for mistreating him.
Nick has Angelman's syndrome and has significant developmental delays. In the court documents, Williams and his wife claimed Cuvillier had a history of physical and emotional abuse toward Nick.
They expressed concerns "that my mother is neglecting and mistreating Nick," court records stated. In that same document, Williams also shared that on one occasion he witnessed his mom "lose her temper and begin punching Nick in the arms, shoulders and back with a closed fist while yelling at him," according to court documents.
He also shared that his dad was the primary caregiver for Nick, and after his death, his mom was in a poor mental state. He even stated in court documents that she "intended to kill Nick and then herself after my father died."
Those same documents shed light on an incident that stems from Jan. 16, when Williams said he went to Cuvillier's home for a welfare check on Nick. This visit escalated to the point where Williams called 911, and court documents show Cuvillier was later arrested and charged with domestic violence assault. While she was in jail, Nick signed a power of attorney making Mack his legal guardian, revoking Cuvillier's prior authority, according to court documents.
Later that month, Cuvillier got a vulnerable adult protection order against Williams. The court also ordered Williams to surrender 53 firearms.
It's unclear what happened in the year since then, and what led up to their deaths this week.
What's next:
FOX 13 reached out to the Mercer Island Police Department, as well as the Issaquah Police Department on Thursday and are waiting to hear back.
This is a developing story. Check back for updates.
The Source: Information in this story comes from original reporting by FOX 13 Seattle.
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