THE MOTHER OF 17-year-old Travyon Martin testified today that her son could be heard screaming in a harrowing 911 call as prosecutors in the racially charged trial in Florida wrapped up their case.

Testifying in the murder trial of neighborhood watch volunteer George Zimmerman, Sybrina Fulton told the court the screams heard on the recorded call to police were those of her unarmed 17-year-old son.

Zimmerman is accused of murder in the shooting death of the African-American teenager in February last year.

The 29-year-old denies the charge, claiming he shot Martin in self-defense after the teen wrestled him to the ground and pounded his head against the sidewalk.

The identity of the person screaming for help on the 911 call has become a pivotal piece of evidence in the case, which has garnered widespread coverage in the US.

Prosecutors say the screams belong to Martin, supporting their case that Zimmerman was the aggressor in the incident.

Defense attorneys have argued however that it is Zimmerman’s cries who are heard, backing his claim that he acted in self-defense.

Martin’s mother however told jurors today she was in no doubt that it was her son’s screams on the tape.

Fulton was played the tape of the call and asked if she recognized the voice.

Asked who she thought it was, she replied: “Trayvon Benjamin Martin.”

Conflicting testemony

The slain youth’s older brother, Jahvaris Fulton, 22, also said he was certain that the person shouting was Trayvon.

Defense attorney Mark O’ Mara however replayed a statement tape during a deposition in which Fulton said he was not entirely sure who was yelling.

“I guess I didn’t want to believe that it was him, that’s why during that interview I said I wasn’t sure,” Fulton said, when asked about his earlier statement.

“Listening to it was clouded by shock and denial and sadness.”

Martin had been visiting a family friend in the neighborhood and was coming back from a convenience store just before his altercation with Zimmerman.

Zimmerman has denied any racial motive in the killing, saying he shot Martin only because he feared his life was in danger.

Zimmerman said he phoned police when he saw Martin walking in a hooded sweatshirt in a gated community in Sanford, Florida which had seen a string of recent robberies.

He told police that he found Martin’s behavior suspicious, and followed the youth even though he had been instructed not to do so by authorities.

Stand Your Ground

The trial has centered in part on Florida’s controversial “Stand Your Ground” law, which permits a shooter to use deadly force if he believes that his life is at risk.

Zimmerman has said in the past that he knew nothing about the law when he shot Martin, but one witness, corporal Alexis Carter, testified that he taught Zimmerman about the law at Seminole State College.

Zimmerman was studying criminal justice courses in hopes of become a police officer one day. Legal experts said the testimony undermines his credibility.

“The prosecution can say to jurors you can’t believe him (Zimmerman),” legal analyst Jack Ford told CBS television.

After prosecutors wrapped up their case, defense attorney Mark O’Mara made a lengthy submission before the trial judge for the case to be dismissed at the halfway stage.

- © AFP 2013.