Cobb man found guilty but mentally ill of killing his mother

Damian Cornell McElrath (left) was convicted of killing his mother Diane McElrath.

Credit: Cobb County District Attorney's Office

Credit: Cobb County District Attorney's Office

Damian Cornell McElrath (left) was convicted of killing his mother Diane McElrath.

Damian Cornell McElrath had already cleaned up the crime scene, called 911 and was smoking a cigarette by the time he told police how and why he killed his mother.

Diane McElrath had been poisoning him for years, Damian said, and according to him she’d even threatened to kill him.

So, when he got the chance, he took a knife from the kitchen, went upstairs and stabbed Diane McElrath in the neck as she was facing away from him, Cobb County District Attorney spokeswoman Kim Isaza said in a news release Tuesday. Damian continued the stabbing, chasing his mom down the stairs as she tried to escape the house.

Now, more than five years later, a jury found McElrath guilty but mentally ill in the July 2012 murder at the west Cobb home he shared with his 58-year-old mom, Isaza said.

The Marietta man, who was 18 at the time, could face life in prison, Isaza said, after stabbing his mother more than 50 times.

This is the second time McElrath was 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, Isaza said, but the judge granted him a new trial after “concluding McElrath had not knowingly waived his right to a jury trial.”

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Authorities say McElrath had long been suffering from mental illness and had been in and out of inpatient care in the months leading up to the murder.

But Assistant District Attorney Jesse Evans, who led the prosecution in both trials, said there was no imminent harm and that McElrath was the aggressor, used aggressive force and admitted to police he killed his mom “over a prior wrong.”

“No one disputes that the defendant has a history of mental illness and antisocial behavior,” Evans said in the release. “But even the defense concedes that he knew right from wrong. Being mentally ill never excuses criminal conduct. Diane McElrath was brutally murdered. This act was never, ever justified under the law.”

Damian McElrath’s sentencing is scheduled for Thursday.

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