(SANFORD, Fla.) -- The markings the fatal bullet left on Trayvon Martin's sweatshirt and body supports George Zimmerman's account that Martin was on top and leaning over him when Zimmerman shot and killed Martin, a leading forensics expert testified Tuesday.
"The medical evidence is consistent with his statement," Dr. Vincent Di Maio told the Florida court.
Di Maio said that the pattern of powder burns on Martin's sweatshirt and skin indicated that the shirt was two to four inches away from Martin's chest when he was shot by Zimmerman.
"Mr. Martin was over him, leaning forward," he said.
"If you are lying on your back your clothing is going to be against your chest," said Di Maio. "The clothing is consistent with someone leaning over the person doing the shooting."
Zimmerman, 29, is charged with second degree murder for shooting Martin on Feb 26, 2012. Prosecutors say the former neighborhood watch captain was profiling and following Martin. Zimmerman maintains that he shot the teenager in self-defense during an altercation in which the teen was hovering over him and banging his head into the concrete sidewalk.
Di Maio, who was put on the stand by Zimmerman's defense attorneys, contradicted the testimony of the prosecution's expert Dr. Shiping Bao on another point.
Bao told the court earlier in the trial that the bullet pierced Martin's heart and would have instantly incapacitated Martin, disputing a key assertion from Zimmerman that the teen sat up and said, "You got me" after he was shot.
The prosecution said at one point, with the jury out of the room, that Bao's testimony raised questions about Zimmerman's credibility.
However, Di Maio testified that Martin may have been able to speak shortly after he was shot.
"If I reached over and ripped out your heart, you could stand there and talk to me for 10 to 15 seconds," said Di Maio.
Jurors furiously took notes as Di Maio, who said he reviewed the autopsy, toxicology, and medical records of both men, said that Martin most likely died within one to three minutes after the shooting. Bao had told the jury Martin could have lived for a painful 10 minutes after being shot.
Zimmerman's legal team also tried to their bolster contention that it was Zimmerman on his back during a fight with Martin on top of him.
Di Maio looked at pictures of Zimmerman's injuries and said that it was possible to receive severe head injuries without visible external injuries.
When asked if the abrasions of the back of Zimmerman's head could have been caused by concrete, Di Maio responded, "Yes."
Looking through photos of Zimmerman's injuries on his face and head, Di Maio told the jury, "You have six identifiable injuries."
Earlier Dr. Valerie Rao testified for the prosecution that Zimmerman was struck as few as three times during the fight with Martin and that his head slammed on the concrete once.
Rao called Zimmerman's injuries "insignificant" and "non-life-threatening."
The testimony followed an early morning evidence hearing, without jurors present, over an animation that the defense wants to use that they claim depicts the fatal struggle between Martin and Zimmerman.
The defense called the person who created the animation who said he sent people in motion-capture suits to re-enact what happened based on coroner photographs, police reports, the coroner's reports and depositions. The prosecution objected to the animation saying it is not an accurate depiction of what happened.
Judge Debra Nelson did not immediately make a ruling.
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