George Zimmerman trial: Defense witness Dr. Vincent J. M. Di Maio

Day 11 of George Zimmerman trial testimony

SANFORD, Fla. – George Zimmerman trial defense attorneys called a nationally renowned gunshot wounds expert to the stand Tuesday.

It was while serving in the U.S. Army Medical Corps. that Dr. Vincent J. M. Di Maio developed a special interest in gun shot wounds.

Di Maio has 40 years of experience as a forensic pathologist. He retired as a chief medical examiner in San Antonio, Texas, in 2006. He said he has performed about 9,000 autopsies and reviewed about 28,000.

Di Maio began his consultancy work in 2007 and charges $400 an hour. He has taught at the University of Texas, and is also a published author.

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Defense attorney Don West asked him to explain the details that were congruent with Zimmerman's account of the Feb. 26, 2012 fatal shooting.

The two most important pieces of evidence in the case are the autopsy report and the fire arms detective review, Di Maio said.

"The underlying facts are supported by the evidence," Di Maio said.

Dr. Vincent Di Maio, a forensic pathologist and gunshot wound expert, describes the injuries of George Zimmerman while testifying for the defense in the trial in Seminole circuit court, in Sanford, Fla., Tuesday.

"The police in this case should have taken Mr. Zimmerman to the hospital ... because he had head injuries," Di Maio said.

The teen's knuckle scrapes were consistent with contact with concrete, he said. And the nose injury  is consistent with being punched, he said.

He also concluded Trayvon Martin "was learning over" Zimmerman at the time of the shot, and that Trayvon would have been conscious enough to move his arms for 10 to 15 seconds after he was shot.

VIDEO: Dr. Vincent J. M. Di Maio explains gun shot.

"The wound in the chest was about an inch to the left of the mid-line, a half inch below the level of the nipples and what you had was a circular punched out wound," Di Maio said.

Zimmerman's gun muzzle was not pressed into Trayvon's chest, and was two to four inches away from the skin, he said.

"If you hold the gun against clothing, this column of air catapults through clothing," Di Maio said.

Prosecutor Bernie de la Rionda said it would also be possible that Trayvon was pulling away from Zimmerman when he was shot, or that the clothing was over sized.

And if Trayvon had his hands on Zimmerman's face, as Zimmerman claimed, Trayvon's hand would have had blood, de la Rionda said. The autopsy report said they didn't have blood.

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