Tracy Martin, the father of the Miami teen who was shot and killed by George Zimmerman in Sanford, was called to testify on Monday.
Trayvon Martin's father was questioned by defense attorney Mark O'Mara about how he said the screaming in the background of a 911 call was not his son.
Tracy Martin said he recalls lead investigator Chris Serino asking him "do you recognize the voice?" Tracy Martin says he answered "I can't tell" and never said "no it wasn't my son's voice."
Tracy Martin denied saying he listened to a "cleaned up" or "enhanced" version of the tape. He also said he never told Martin's mother, Sybrina Fulton, about listening to the tape.
"After listening to it maybe 20 times, I said that I knew it was Trayvon's voice," Tracy Martin said of the March 16, 2012 tape playing in the Sanford mayor's office.
During cross-examination, Tracy Martin called Trayvon Martin, "my best friend in life."
"It's still hard to believe this day that he's dead," Martin said.
The defense objected to the state broadening its questions beyond the scope of direct. The objection was apparently overruled at bench as the state asked about identifying his son's body in a photo the day before the Sanford Police Department meeting.
"My world has been turned upside down," Tracy Martin said. "I was listening to my son's last cry for help ... his life being taken."
Tracy Martin said he played the screams repeatedly, "trying to figure out ... why did the defendant get out of his vehicle and chase my son."
The defense then called former Sanford Police Chief Bill Lee to testify. Lee said it's proper to do lineups with individual witnesses, not as a group, "so their decision is not influenced" by others.
Lee said he was intentionally excluded from playing tape for Martin family by city manager and that he offered to be present.
"Evidence and testimony gave us an indication" of whose voice was screaming" but lee said they were looking for corroboration.
After Lee's testimony, Nelson dismissed the jury for the day to conduct a Richardson hearing for a state motion claiming they weren't told one of the defense witness' testimony had changed.
Earlier on Monday, O'Mara questioned Serino on when Tracy Martin, arrived at the Sanford Police Department. Serino said two days after the shooting he played the 911 audio at his desk. Serino described Tracy Martin as giving an emotional response and when he asked if Tracy Martin recognized the screams, Martin looked away and said under his breath, "no."
During cross-examination, prosecutor Bernie de la Rionda asked Serino if he had warned Tracy Martin he would hear the gunshot in the background of the 911 call.
Serino said he didn't recall warning Tracy Martin and played all 911 calls, including the emotional 911 call from witness Jane Surdyka. Serino said he expected Tracy Martin to be very emotional.
Serino said he asked Tracy Martin either "do you you recognize the voice?" or "is that your son's voice in the background?" De la Rionda asked if Tracy Martin's response about the 911 calls "could be construed as denial. Serino agreed.
Tracy Martin has previously said call quality and environment at SPD prevented him from being certain it was his son's voice, but later said it was.
During redirect, Serino told O'Mara Tracy Martin's denial "became significant in the investigation" because other witnesses had information it was Zimmerman. Serino said Zimmerman didn't deny it was his voice, in context, he was saying his voice sounded unusual to him and not clearly recognizable.
Sanford Police Department Detective Doris Singleton testified that Martin's father, Tracy Martin, was at the department asking why no one was arrested. The state objected to O'Mara asking Singleton what Tracy Martin said as hearsay.
Singleton was called again after Serino's testimony to back up fellow officer Serino's recollection that Tracy Martin didn't recognize the vioce.
Singleton testified that Tracy Martin was "very upset, very sad, he hung his head and cried." Singleton said Tracy Martin listened to the 911 call with screams at the police station two days after the shooting.
Jurors then heard from Adam Pollock, the owner of the gym where Zimmerman took mixed martial arts classes. Pollock testified about the "ground and pound" and demonstrated the MMA move on O'Mara.
"When you're on top you have gravity working for you," Pollock said, adding that punches from above carry more force.
Pollock waved to Zimmerman, who joined the gym in 2010 wanting to lose weight and get in shape. Zimmerman wanted to learn boxing but did grappling, Pollock said. Pollock described Zimmerman as "physically not an accomplished individual." He was a 0.5 on a scale of 1 to 10, Pollock said and after working for many months, Zimmerman rose to a 1.5 out of 10 but was "physically soft."
Zimmerman tried boxing as well but wasn't skilled enough to be in the ring, Pollock said. After the shooting, Pollock described Zimmerman as being "a human being who had been through an extremely traumatizing experience."
Sondra Osterman was the first defense witness called to the stand on Monday. Her husband, Mark, an air marshal testified earlier in the trial. Osterman said she has known Zimmerman since 2006.
Osterman listened to the screams on the background of the 911 calls, which captured the confrontation between Zimmerman and 17-year-old Martin shortly before Zimmerman fatally shot Martin.
Defense attorney Mark O'Mara asked if her friendship with Zimmerman would affect her opinion.
"I wouldn't lie for him or anybody," Osterman said. O'Mara asked if she knew whose screams they were.
"That's definitely Georgie," Osterman said.
Prosector Bernie de la Rionda asked Osterman about the book she co-wrote with her husband, in which proceeds will be donated to Zimmerman after the trial. Osterman said she doesn't know how many books have sold and the money is being put in their savings account for Zimmerman after the trial.
De la Rionda then played the non-emergency 911 call where Zimmerman says "these a******* always get away" and "f****** punks." Osterman identified the voice as Zimmerman.
During redirect, O'Mara asked if Osterman had heard Zimmerman scream like that before, to which she said she hasn't. He also asked if there was anything in the call that was said with spite, hatred anger or ill will, to which she said no.
"Aren't you just speculating about Zimmerman's state of mind the night of the shooting?" de la Rionda asked during redirect.
"We both are," Osterman replied.
The defense then called Mark Osterman to testify. Mark Osterman, who says he's Zimmerman's best friend, testified for the state last week and said he advised Zimmerman on the type of gun to buy if he were going to get a concealed weapons permit.
The 911 call was played again in court and Mark Osterman said the voice is Zimmerman, based on the tone.
During cross-examination, de la Rionda questioned Mark Osterman on the book and how many copies were sold. Osterman said he wasn't sure.
De la Rionda also asked Mark Osterman on what he taught Zimmerman about guns.
"You made him a better shooter?" de la Rionda asked.
"I hope so," Mark Osterman replied.
The defense's third witness of the day on Monday was Geri Russo, who works at Digital Risk--Zimmerman's employer at the time of the shooting.
Russo testified the screams in the background of the 911 call was Zimmerman. The defense hopes their five testimonies of Zimmerman scream identifications outweigh the state's two witnesses for the jury.
During cross-examination, prosecutor John Guy mentioned testing between Russo and Zimmerman.
"My immediate reaction was that's George's voice," Russo said.
The fourth witness of Monday and the sixth overall was Leeanne Benjamin, a realtor who referred clients to Zimmerman when he was into insurance in 2003. She encouraged Zimmerman to go to college and said she was proud of Zimmerman for tutoring young children.
Benjamin said her friendship with Zimmerman wouldn't change her testimony before the state had Benjamin listen to the 911 calls with the screaming in the background. She said the screaming was Zimmerman and that she's heard Zimmerman's voice in a "very similar" manner.
Benjamin said she and her husband contributed $2,500 to George Zimmerman legal defense fund, plus clothing.
During cross-examination, de la Rionda had Benjamin examine Zimmerman's voice on his call reporting the and if Zimmerman was outside or winded during the non-emergency call.
Benjamin said that profanity doesn't always indicate anger, as de la Rionda raised his voice demonstrating Zimmerman's words on the call.
The defense then called Benjamin's husband, John Donnelly. Donnelly said as a Vietnam War veteran he was able to develop ability to distinguish screaming voices.
O'Mara then played the 911 call with the screaming in the background for Donnelly.
"There's absolutely no doubt in my mind that's George Zimmerman," Donnelly said, wiping tears from his eyes on the stand.
The prosecution said it has an issue to discuss with the judge, likely over Donnelly not listening to screams until after deposition.
Donnelly testified he donated $4,700 in cash and clothes to Zimmerman and his defense fund.
"I think of him as a son," Donnelly said.
Also on Monday, the state filed a motion to block the defense from presenting a computer-animated reenactment showing the altercation between Martin and Zimmerman to the jury, citing speculation, incompleteness and late discovery.
The defense called its first two witnesses Friday after prosecutors rested and Judge Debra S. Nelson denied a request for acquittal.
Zimmerman's mother and uncle testified that it was Zimmerman screaming for help on a 911 call that captured the fight between Zimmerman and 17-year-old Trayvon Martin.
Zimmerman, 29, has pleaded not guilty to second-degree murder for fatally shooting Martin, claiming self-defense.
It's still uncertain whether Zimmerman will testify.
Jurors already have heard his account through videotaped police interviews played in court.
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