Death's Acre: Inside The Legendary Forensic Lab The Body Farm by Bill Bass (essential books to read txt) 📕

anyhow, the academic equivalent of a football walk-on, hoping to snag a place on the starting team a week before the opening game. I shoehorned him into classes in archaeology and osteology, hoping that a slot in the forensics program would open up soon—and that Steve would still be interested by then.

It did, and he was. He quickly absorbed the rest of my osteology handbook, thereby earning a place on our forensic response teams. The walk-on had done it: He’d made the anthropological equivalent of varsity first string. In the field, Steve showed a quick grasp of crime scene investigation. Equally important, he was a superb photographer. When it comes to crime scene photos, more is always better, and great is always best. Steve’s crime scene photographs were—still are—the best I’ve ever seen.

After eight long years of graduate work and crime scene assistance, Steve passed his doctoral examinations, then took a job as the staff forensic anthropologist for the medical examiner in Nashville. Besides working full-time for the ME, Steve planned to research and write his Ph.D. dissertation there in Nashville. His topic: estimating age by examining the sternal end of the clavicle. (“The collarbone’s connected to the . . . breastbone. . . .”)

Then came another one of those pivotal points in Steve Symes’s life. During the course of a few violent weeks in Nashville, Steve was handed three dismemberment cases. The detective working one of the cases pointed to a notch in a bone and asked Steve to tell him about it. Happy to have a chance to display his expertise, Steve drew himself up and said, in his most professorial voice, “Why, that’s a saw mark in an arm bone.”

The cop stared at Steve in disgust. “I know it’s a saw mark in an arm bone,” he snorted. “You’re the bone doc; what kind of saw mark?”

Steve didn’t know, but after he finished blushing, he decided to find out—not just about that particular saw, but about all types of saws.

At this point I can’t help but add that I’d been trying for years, unsuccessfully, to interest a graduate student in researching saw marks. We’d had a sensational dismemberment case in Knoxville in the mid- 1980s. A love triangle turned hateful, and the woman and one of her men ended up killing her other man, then cutting him up and scattering the pieces all over town. That case had gotten me to thinking about how little we knew about what evidence might be left behind by a saw as it cut up a body. But nobody seemed inclined to pursue the topic, including Steve, until that bloody Nashville summer when he found himself butting up against the problem not once but three times.

Police departments and courts all over the world have long considered ballistics evidence to be scientifically credible. Just like people, guns leave fingerprints: A pistol’s firing pin makes a consistent impression in every cartridge it strikes; the rifling in the barrel leaves characteristic grooves on each slug that spirals toward a victim; the ejector mechanism scratches or dents every spent shell case the same way as it kicks it out of the breech.

If guns leave telltale marks, why wouldn’t saws? Steve and I felt sure they would. At the time, though, we seemed to be in the minority. Conventional wisdom held that every stroke, every pass of a saw erased the marks left by the previous stroke; in other words, saws covered their own tracks. Steve made up his mind to prove that they didn’t—that there was a world more detail to be seen, a world more evidence to be gathered.

Over the next two years Steve bought or borrowed every kind of saw he could lay his hands on: ripsaws, crosscut saws, hacksaws, jigsaws, coping saws, circular saws, chop saws, Japanese pull saws, and more. He spent several weekends with Dr. Cleland Blake, an East Tennessee medical examiner who was also a master woodworker—and studied hundreds of saw blades in Cleland’s collection, ranging from jewelers’ trim saws to lumberjack-grade chain saws.

Clamping donated arm bones and leg bones in his bench vise, Steve made thousands of experimental cuts and studied them through microscopes. At first, he saw little that seemed meaningful. Eventually, though, he found the key. Peering through a surgeon’s operating microscope and angling light across the cut marks, he saw a world of three-dimensional detail open before his eyes: immense canyons and jagged cliff faces carved in bone. He took countless micrographs, plaster impressions, and measurements, cataloging push strokes, pull strokes, rotary cuts, false starts, skips, hesitations, and other telltale marks left by saws as they ripped through the bones.

I’ll never forget the first time Steve hauled me into a lab, led me to a stereo microscope, and gave me a stroke-by-stroke replay of the saw marks in a femur he had clamped in a vise and sawed in half. Etched forever in a cross section of bone—as they are now in my mind’s eye as well—were the zigzag bite marks left by individual teeth sliding back and forth, chewing their way relentlessly downward through the bone in a series of shallow, Z-shaped tracks. It was a moment that made me proud and humble at the same time: The student—my student—had surpassed the teacher, in at least this one macabre specialty.

Eventually, Steve was able to look at a bone fragment from a murder and see far more than “a saw mark in an arm bone”; eventually he was able to discern, for instance, the tracks of a ten-teeth-per-inch crosscut saw, with a kerf (cut) width of 0.08 inch, created by alternating offset teeth, cutting on a push stroke—a stroke interrupted, he might observe, by three skips, two false starts, and one temporary halt. A husband cutting up his wife’s body wouldn’t mean to leave such telltale tracks behind, any more than a hired shooter means to leave ballistic evidence on his bullets. It’s simply the unavoidable consequence.

Steve never got around to writing that serviceable, boring dissertation on the sternal end of