New Albany Police Chief Sherri Knight said during a news conference Friday that mental illness, including postpartum depression, was the underlying factor in the deaths. Knight added that authorities didn't know whether Clutter committed suicide or drowned by accident, noting that "hypothermia was a significant contributing factor" in her death.
A witness told police that the mother and children weren't properly dressed for the 30-degreee weather that day. Independent mental health professionals hired by the police department to review the case said mental disorders could be intensified when subjected to cold temperatures, Knight said.
Detective Carrie East said Clutter's behavior "was concerning" to some witnesses leading up to the deaths, saying she made "incoherent statements" and displayed "delusions of grandiose proportions of demonic presences," including saying her family was being stalked by those demonic presences.
The case had been the subject of intense speculation because police hadn't disclosed much information since the bodies were found. Floyd County Prosecutor Keith Henderson had said he planned to call a special grand jury to investigate because police were taking so long with their investigation.
Henderson was out of town Friday and could not be reached for comment, a spokeswoman said.
Knight said marks found on Clutter's body were consistent with being in moving water. The man who found the bodies in the creek had told 911 dispatchers the woman's body appeared battered.
The Clutter family moved to New Albany from the Seattle area in December.