(CBS/AP) MARIETTA, Ga. - Closing arguments are underway in the trial of De'Marquise Elkins, the man accused of fatally shooting a baby in a stroller in coastal Georgia.
Elkins is charged with murder in the March 21 killing of 13-month-old Antonio Santiago in Brunswick.
His mother, Karimah Elkins, is on trial alongside him on charges of evidence tampering and lying to police.
Closing arguments began Friday morning. At their conclusion, the jury will begin deliberations.
Prosecutors say Elkins killed Antonio in an attempted robbery. The baby's mother, Sherry West, was also shot. If convicted of murder, 18-year-old Elkins faces up to life in prison.
Fifteen-year-old Dominique Lang is also charged with murder in the case and will be tried later.
The baby's mother, Sherry West, told jurors Tuesday that two teenagers approached her as she walked home from the Brunswick post office March 21. She said the older one demanded money, tried to take her purse and threatened to kill her baby. She said the teen fired a warning shot, shot her in the leg and then shot the baby.
She said she threw her arms across the boy, trying to protect him.
The killing this spring in the port of city of Brunswick, close to vacation spots like Jekyll Island, drew national attention, and the trial was moved to the Atlanta suburbs because of the extensive publicity the case received locally. In opening statements, Johnson told jurors that both shootings started off as robberies.
In opening statements defense attorney Jonathan Lockwood suggested that Antonio's parents were somehow involved in his death, though he did not provide a precise motive or further explain that theory. He said that no one in the neighborhood saw or heard anyone fleeing the scene of the shooting.
He also questioned whether police focused their investigation too soon on the wrong suspects. He said that West tried to collect on a life insurance policy shortly after her son's death.
"The police were under a great deal of pressure to see that the matter was resolved as vacation season was not far away," Lockwood said.
Defense attorneys detailed the life insurance policy in a pre-trial motion filed Aug. 5, which also alleged West is mentally unstable and gave inconsistent accounts of her son's murder.