Markeith Council is charged with voluntary manslaughter in connection with 40-year-old Shon McClain's death.
Surveillance video played for the courtroom Tuesday morning showed an encounter between Council and McClain on June 4.
The video, which did not include audio, showed McClain with a towel around his neck, approaching Council. The two began to argue and Council was seen pushing McClain, who fell to the floor, then got back up and moved toward the jailer.
McClain raised his hands and then swung at Council. The corrections officer threw McClain to the concrete floor, then picked him up and did it again -- head first.
McClain never regained consciousness and was on life support for almost two weeks at WakeMed before he died.
According to his autopsy, he died of blunt force trauma to the head and neck.
Since there was no sound with the video, the District Attorney called another inmate to the witness stand Tuesday to tell jurors what he heard during the June encounter.
He told jurors the two men had argued over bed sheets and when McClain got in Council's face, Council made a comment.
"The officer was like 'I'm going to (expletive) you up when you get out' after the argument had already started," Wake County Detention Center Inmate Jeremy Nelson said.
On cross-examination, Nelson admitted he didn't initially tell State Bureau of Investigation agents investigating McClain's death about that alleged statement.
McClain's family is in the courtroom but his sister leaves every time the video is played.
"I can't watch the video," said McClain's sister, Marlene Gilbert. "I don't want that last image in my head of him being slammed to the floor."
The district attorney spent much of the day calling eyewitnesses to fill in the blanks left by the lack of audio. They say Council and the victim had an ongoing argument. Some say Council threatened McClain.
According to court documents, McClain was in jail on charges of drinking at a Raleigh bus station and possession of paraphernalia. He was from Apex.
Council had been on paid administrative duty pending a review by the SBI. He was later suspended without pay and indicted.
The prosecution has wrapped. The defense will wrap Wednesday. Then jurors will have to decide if Council is guilty of involuntary manslaughter.