Its CSI Burlington, right on the UVM campus. About three minutes into Dr. Paul Morrows March 5 lecture on gunshot, blunt force and sharp injury trauma, he brings up a slide: a close-up shot of a man with a self-inflicted gunshot wound to the head.
Its a very small, round wound that superficially doesnt suggest the damage it caused on its way through the brain. Morrow asks students to look closely for the presence or absence of specific features around the entrance wound, such as a rim of abrasion, wipe off debris from the firearm, or an abrasion collar, which would indicate the bullet entered at an angle. Then they look at the exit wound on the other side of the mans temple; it is wider, with a more irregular shape what Morrow calls yawing.
Morrow, who is Chief Medical Examiner for the State of Vermont, was last weeks guest lecturer at the universitys first-ever seminar series in forensic biology. The seminar is the cornerstone of a new concentration in forensic biology in the College of Arts and Sciences Department of Biology that has already been of great interest to prospective students, says Judith Van Houten, professor and chair of biology. As television programs such as CSI glamorize the important role of forensic scientific techniques in solving crimes, more and more students are gravitating toward colleges that provide training and prepare them for careers in the field.
Morrow next shows a slide of another person with a large purplish spot on the bridge of his nose. Entrance or exit wound? Morrow quizzes the students. The answer: its an entrance wound, messier than the usual because the bullet passed through the unlucky persons eyeglasses. Knowing what the bullet encountered before it hit the victim, Morrow says, is imperative to getting a full picture of the crime.
The austere classroom is packed with students. The walls are bare except for a poster of the periodic table, the air quiet except for the hum of the slide projector. Students occasionally ask questions, and when the lecture runs overtime, few take the opportunity Morrow gives them to leave. The medical examiner is only one of several guest instructors at the weekly seminar, in a roster that includes State Toxicologist William Bress; Detective Sergeant Joseph Lehy of the Vermont State Police; Eric Buel, Director of the Vermont Forensic Laboratory; and Vermont Attorney General William Sorrell. Seminar topics include DNA technology, post-mortem changes, investigating arson and laboratory techniques.
Painful subjects
Take rifle and handgun injuries, for example. Different types of firearms create different types and severity of wounds. When fired, every gun produces bullets with unique grooves and ridges, called tool marks, that makes it possible to match any bullet to a particular gun. Its always important to get the bullet, Morrow says. (And by the way, never handle a bullet with metal it compromises the unique markings.) Moreover, the explosion that sends the bullet spinning through air also expels hot gases, smoke, soot and little bits of burning gunpowder. Its the presence, absence and/or location of this debris, along with ballistic testing, that lets crime scene investigators know at what range the gun was fired.
Medical examiners are always reminding emergency-room personnel to save patients clothing, says Morrow. The clothing can tell you more of the story. He shows a slide of skin surrounded by a small, round gunshot wound that suggests a gun was fired at tight contact, against the victims body. But in this case, a Harley Davidson decal on the victims vest (shown on another slide) absorbed the telltale debris that reveals to investigators the gun was fired from further away.
Morrow moves on to blunt trauma, such as blows, beatings and falls. Contusions, or bruises, often hemorrhage internally into tissue. He brings up a slide that shows a bruised brain. The distribution of bruises, scrapes and cuts can tell us something about the injury, Morrow says. In this case, the bruising was induced by a motorcycle accident. There are also characteristic patterns on victims of automobile accidents. And the location of wounds provides even more information. Cuts on the hands can often be defensive wounds from warding off an attacker. Drag wounds show up on the victims skin, indicating foul play.
Sharp force injury is yet another source of trauma. Cutting, stabbing and puncture wounds tend to gape according to the normal elastic lines of the body, Morrow explains. Consequently, the edges of sharp injury wounds must be re-approximated before they are measured for potential weapons. And, as with blunt trauma, the distribution of injuries helps medical professionals determine cause of death, from the slashed wrists of a suicide to the patterned puncture marks of a pitchfork injury.
Morrow then shows slides of a victim and a crime scene to summarize a case involving a body that washed up on the banks of the Winooski River. The victim suffered a severe head injury, but how? Both from bodily evidence and from bloody sneaker prints and blood on a rock near the area where the body was recovered, Morrow deduced that the victim had been struck on the head with the rock, and then dragged to the water for disposal.
Add a few good-looking actors, and it might be a plot for an upcoming episode of CSI.
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