One of the teens accused of robbing and murdering a pizza delivery man in North Charleston last year pleaded guilty to a lesser charge this morning in St. George. He was sentenced to 20 years in prison.

Jontae Davis, 18, of Charleston, pleaded guilty to voluntary manslaughter and armed robbery. Davis, who originally had been charged with murder, will testify against his co-defendant, Stephawn Brown, 19, of Charleston. Brown is charged with murder and armed robbery.

Davis’ plea came just before the trial for the two defendants got underway this morning. During opening statements, prosecutors pointed to Brown as the triggerman in the armed robbery and murder of Maraleius Birdsong, 20, a Domino’s Pizza delivery driver and a student at Trident Technical College was shot in the head on March 9, 2012.

Prosecutors told the jury that the defendants called in a bogus order from Domino’s Pizza for chicken wings and cinnamon sticks.

Birdsong knocked on an apartment door at Appian Way Apartments in North Charleston, according to prosecutors. The people who answered the door to Birdsong turned him away and suggested that he try another apartment, where no one answered the door, according to investigators. After he was unable to find those who ordered the food, Birdsong walked back to his car in the parking lot. That’s where he held up for the boxes of food and was shot in the back of his head as he tried to run away, prosecutors said.

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Reach Natalie Caula at 937-5594.