The Georgia Bureau of Investigation found that Sammie Davis Jr. suffered from schizophrenia. That's according to Bibb District Attorney David Cooke.
Davis was shot and killed by Macon police officer Clayton Sutton outside of a Macon grocery store on December 21st.
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Shannon Harvey, CEO of River Edge Behavioral Health Center, says researchers believe the mental illness is caused by a problem with brain chemistry or structure.
She says people with schizophrenia often have hallucinations, anxiety, and odd social behaviors. She explains that those symptoms usually result in subdued behavior, but sometimes patients will react to the hallucinations.
"A lot of times when people with schizophrenia appear violent, it's because their brain chemistry causes them to believe they're under threat. So, they're acting in self-defense in a world that they live in," adds Harvey.
She says medications can prevent many of those problems, but only if taken properly.