DR. VINCENT Di MAYAO: forensic pathologist for 40 years. Brilliant and clear. Med degree from NY in 1965. Interned at Duke. Lots and lots of academics and practice. Board Certified in anatomical, (moles, tissues), clinical (lab work), and forensic (how'd they die), pathology. After medical school, he joined the Army as a Major attached to Walter Reed Hospital. Then became med examiner in Texas. In 1981, he became chief medical examiner of Bexar County, San Antonio, TX until 2006. Crime lab chief also. Editor in Chief of The American Journal of Medicine and Pathology. He's Chairman of Texas Forensic Oversight Agency. Oversees state pathology labs. Before he formed the Agency, the cops had their own labs. He established first Texas DNA lab. Included how to package evidence and techniques to establish chain of custody and packaging of wet evidence. Each item must be packed individually in paper, not plastic. In plastic, you get mold and stink and deterioration. Paper is standard practice for 30 years. Full professor at UT in pathology. Published 88 articles, 13 book chapters, 4 books, one about gunshots and book on pathology with his dad who was Chief Medical Examiner of NY. Wrote Handbook on Pathology and book about Excited Delirium Syndrome with wife, a pathology nurse. His book about gun shot wounds going into 3rd edition and is printed in four languages. Example, range of shot, nature of weapon, how to describe things in reports, did shots into gelatin for effect of ordinance. Has done 9000 autopsies and 28000 reviews of other autopsies. Typically appears for prosecution. These days he is hired by insurance companies for suicides and accidental deaths.
Mechanics of shot - He developed micro flash photography. Firing pin hits primer, ignites, passes into cartridge case, powder burns, converts to gas and builds pressure, pressure pushes bullet out, bullet gripped by rifling, gas will get in front of bullet, bullet pushes gas and air out in front of it in a cloud as it exits the barrel. In flash photo you see cloud of gas, and air, the bulk of the gas exits with the bullet and along with burning and unburned powder. When gun is against clothes, gas and air tears fabric, then bullet passes through hole with soot and gas. That's why blanks are deadly. Gas projection will kill you. No need for a bullet in a contact shot. Worked for US govt. in the New Orleans cop shooting. Testified for Marines in War Crimes trials. In Belfast he testified for British gov't. He testifies for the UN in Yugoslavian war crimes trials. Been in court in most states in the Union, state and federal courts and South America, So Africa, and in Israel. Gotten awards and medals. He's written on blunt force trauma.
In this case he reviewed scene photos, photos of TM, tox report, autopsy photos, EMS report re GZ, he read witness statements of John Goode, he heard the 911 tape, DNA stuff, fire arm expert report and depo of Dr, Bao, prosecution's med examiner. He also saw the video re-enactment of GZ on scene. He says Witness statements vary greatly. He looks first at physical evidence like clothes and the wound to then see if statements are consistent. Most important to him in this case was the autopsy report and report from fire ams examiner then the rest. His task Included reaching an opinion about distance of shot and appearance of wound and skin. Here, how long was TM alive and conscious, if those are different, what are injuries of GZ and injuries of TM.
Gunshot: He saw in photos contact discharge against clothes. At time of discharge, gun against clothes, soot, tearing. Wound is different. To left of midline, circular with powder tattooing. Powder hits skin and creates powder tattoo marks. Person was alive at time of contact because of redness. As you move away the powder marks spread out and disappear after three feet. In this case 2x2 inches of powder tattooing so gun was not against skin. Gun was 2 to 4 inches from skin. So gun was up against TM's clothes but clothes were 2 to 4 inches away from TM's body. In the past this doctor has studied and experimented with powder tattoo. Type of powder necessary to be accurate. Clothing in this case did not affect powder tattooing on body because gas made hole in shirts and powder went through hole and tattooed the skin. If gun had been hard pressed on TM, there would be a halo of black soot but no powder tattoo. Powder would be inside the body. Hard call here? No. Basic 101.
Trajectory: X-ray is better to see with and he saw TM's. Autopsy report describes entry of bullet between 5th rib space, hit heart sack and right ventricle, in and out, and then into right lung. From front to back and left to right. The right to left trajectory is very slight. L to R is from victim's point of view. Not straight on shot. Doctor says the evidence he reviewed is consist with GZ's version of events. Medical evidence of the wound and tattooing is consistent with GZ's version. Gun was in GZ's right hand. Most important evidence is clothing because when TM leaned over GZ, his clothes were away from his body. That's consistent with GZ's claim that TM was on top and leaning over GZ. Dr. DiMaio considered the wetness of TM's clothes and considered the full can of ice tea in pouch of TM's hoodie. These tended to re-enforce his opinion because wet is heavier than dry and something heavy pulls clothes away from the body, so it's consistent with GZ's account that TM was on top leaning over him when GZ shot.
Effect of shot on Trayvon Martin: When conscious, he had ability to move depending on oxygen reservoir in his brain. Reservoir lasts about 15 seconds, depending on blood pressure and you could speak and walk. Then he discusses how long the heart will beat with a hole in the ventricle and a hole in right lung. So he's losing blood and the heart beat pumps out. In a struggle the heart rate increases. When shot, TM's heart was beating, let's say, 100 times a minute. If he loses one tablespoon of blood every time the heart beats, 15 cc's, he's losing 1500 cc's per minute, a quarter of his blood supply. In the second minute, more than half his blood supply, then he is going to die, Here, in all probability, he will have died within one to three minutes of the shooting. Electrical activity may continue but of no use. Q: Ever see this injury where victim could walk and talk? A: Yes. Shot gun at point bank, heart shredded but he ran 60 feet before collapse. Some people don't move from psychological effects. QQQQQ: Could TM have put his hands under his body in those 10 to 15 seconds? A: Yes If unconscious, no pain and no movement.
Trayvon Martin's knuckle injuries: Abrasion. Consistent with impacting hard surface like concrete. Expect to see bruising in fight? A; Maybe but you have to cut in and find blood and you can punch without bruising. No blood pressure when dead, so no bruising to be seen. Dr. Bao did not cut to see.
George Zimmerman's injuries: Photos from scene and hours later. Blunt force injury to head results in brain sheer, shifts like jello back and forth. Bruising, bleeding, inter-cranial stuff, you die. OR, injury to the connective tissue injury cell to cell Axons stretch. Limited motion like bumping head but movement violent, stretching the axons and injury to wall. In auto accident, hits panel will injure axons and they cannot heal and they die. You can afford to lose some cells but at some point impairment or die. GZ could have inter-cranial injury. Hit on concrete, head yields not concrete. You could die or injure brain but there will always be a stunning effect, Concussion, some can take it some can't. First stunning, then concussion and then worse, depending on force and how many times. When your head hits with sufficient force to tear flesh, you will be stunned. No question. Hair is no help. With lacerations, there's some trauma. Here, two lacerations and bruising. Dr. points to two lacerations but says look at swelling. Swelling shows two distinct impacts. Swelling is hematoma. Impact flattens site. Two areas of swelling so two impacts. Lacerations occur in direct perpendicular impact, skin is crushed. Lacerations also occur with a bang and then a slide on a surface which holds a piece of skin and the rest moves so it tears. Laceration in this case is more of a marker of force. Indicates severe force. Not a bump on the head. Sometimes children don't show trauma outside but CT will show fracture. Gaging these injuries, this injury will definitely cause stunning. Additional blows will compound injury. People can die. One week football injury then next week another hit, he can die. Stunned is not knocked out.
Punctate abrasions and facial injuries: Little red marks on head indicate impact on nubby surface. Concrete. So head hit sidewalk. Then lump or knot is hematoma associated with punctate abrasions. One or more impacts. On R side of head, he sees impact of some sort. Reddish areas visible. L side photo, we see punctate marks and swelling suggestion from an impact. Blunt force trauma evident. GZ's face, outline of nose, shows swelling, abrasion, bulging is consistent with displaced fractured. Punch in nose. In later photo suggests that he had displaced fracture and someone pushed it back in. Hit hard in the face and another blow also seen in forehead not consist with concrete but with punch. Different from nose injury. Six identifiable injuries. May be others but photos are poor. He assumes resistance from GZ so there might be more impacts but 6 he can see.
Cross Examination: Witness statements go more toward manner of death.