The stab wounds were concentrated to the woman’s face, neck, upper torso and upper extremities, the medical examiner determined.
By the time police arrived, Damian McElrath, who was 18 in 2012, had already cleaned up the crime scene, lit a cigarette and called 911 to explain how and why he killed his mother, AJC.com previously reported. He also detailed his reasoning for killing his mom in a handwritten letter titled “My Antisocial Life.”
McElrath, who has a history of schizophrenia or a related schizoaffective disorder, claimed the 58-year-old had been poisoning his food and beverages for years and that she’d even threatened to kill him, authorities said.
“On the day before the stabbing, or slightly earlier, McElrath believed that Diane confronted him and admitted that she had been poisoning him,” Chief Justice Harold Melton wrote in the court’s decision.
The week before the fatal stabbing, McElrath had to be hospitalized in a mental health facility because of his behavior and thoughts, which included delusions that he was an FBI agent, authorities said.
In 2017, McElrath was found guilty but mentally ill on charges of felony murder and aggravated assault, but not guilty by reason of insanity on one count of malice murder.
It was the second time he’d been convicted of killing his mom.
He was found guilty of the crime in a March 2014 non-jury trial and was sentenced to life in prison, Cobb prosecutors said, but the judge granted him a new trial after “concluding McElrath had not knowingly waived his right to a jury trial.”
On Friday, the state’s highest court vacated McElrath’s latest conviction and ordered a new trial after ruling that his convictions were contradictory.
“In this case, the jury must have determined that McElrath was legally insane at the time that he stabbed Diane in order to support the finding that he was not guilty of malice murder by reason of insanity,” Melton wrote. “Nonetheless, the jury went on to find McElrath guilty but mentally ill of felony murder based on the same stabbing — a logical and legal impossibility. For this reason, the verdicts in this case are repugnant, both verdicts must be vacated, and McElrath’s case must be remanded for a new trial.”
Cobb County District Attorney’s Office spokeswoman Kim Isaza said prosecutors plan to retry McElrath, but it’s unclear how soon a new trial could be scheduled.