Davon Thomas turned down a prosecutor's offer to plead guilty and go to prison for 20 years in connection with the killing of Tigist Yemane in November 2009.
Thomas told a judge Tuesday that he understands that by going to trial, he is risking a sentence of life in prison without parole if a jury finds him guilty of first-degree murder.
In a motion filed with the court, Thomas' attorney said that his client suffered from post-traumatic stress disorder after returning from a tour in Iraq, and that he was delusional when he shot and killed Yemane, who had moved to Charlotte from Ethiopia.
"He had a flashback, thinking he was back in Iraq, and that is what has happened," Thomas' mother said after the hearing. "He saw, unfortunately, this young lady as a terrorist -- a suicide bomber."
Thomas' mother and other family and friends said Tuesday that he changed after enlisting in the Army and going to Iraq, going from a friendly, outgoing teenager to a young man who needed help with his mental disorder but didn't get it.
"This is the result of the negligence of the military and our government," his mother said.
But the family and friends of Yemane find that explanation hard to accept.
"Whether he snapped or he didn't snap, it doesn't change the fact that Tigist is gone to be with the Lord," said Loretta Caldwell, who took Yemane in after she moved to Charlotte from Ethiopia for heart surgery.
Caldwell said they will be there to watch the case as it goes to trial, which will probably be sometime in 2012.
"We have to stand behind the system, and we are standing behind the system that justice will prevail and the truth will be known," Caldwell said.