Hard Evidence

The most obvious clues of criminal intent include gasoline trails or "splash and dash" burn marks on carpeting, furniture and walls. Window glass provides other clues: Long shards directly inside the windowsill point to a prior break-in, while small chunks of crazed glass suggest a heat-related shattering. Where did the fire start? Look up: "Lightbulbs have the obliging tendency to bubble and extend toward intense heat, as if to say, 'Look here, dummy,'" explains Dalton.




Earlier the same morning, the class looked without a flinch at Devlin's PowerPoint presentation from hell. The close-up photographs featured one fire fatality after another, each graphically illustrating the telltale signs that distinguish victims who perish during a fire from those already dead when the fire began—the latter being a red flag for possible homicide. A mask of soot around the nose and mouth, for instance, paints the picture of a fire victim still gasping for breath when engulfed. A face-down position suggests an attempt to crawl to safety or huddle from overhead smoke. A face-up victim raises more questions. On the other hand, Devlin warns her students against mistaking the drawn-up "pugilistic pose" of a severely burned corpse as a sign of struggle or self-defense. In fact, the pose results from the contraction of cooked muscle.




After a break to let the torched Chevy cool, Devlin herds students to the smoldering vehicle and cajoles them to reach into the char to gauge the fragility of the cremated remains. The student investigators have more difficulty with Devlin's mock human victims—three animal carcasses were burned in this car—than with the half-dozen cadavers they handled in previous weeks at the state morgue and Body Farm. They hang back. So Devlin pushes open the trunk and picks up a molar from the blackened remains of a raccoon. "What if this is the tooth you need to make a positive ID?" she asks, pinching it to dust between her thumb and forefinger. "Oops."




As students begin handling the charred bones, Devlin points out that though the hands, feet and facial characteristics have burned away, the underside is intact: There is not so much as a singed hair where the body rested against the trunk floor.




Devlin also wants her CSIs to experience the difficulty of distinguishing charred bones from other fire debris. Among her class exhibits she includes a dark version of "Where's Waldo?"—a trough of charred skeletal remains mixed with look-alike fire debris such as burned and crumbled ceiling tiles.




The previous weeks of fieldwork have already sharpened the students' powers of observation in ways they had not imagined possible. During a Week 5 daylong exercise in "surface scatter," the class divides into two teams, each assigned to recover a separate set of 30 skeletal fragments in different sections of the Body Farm. Instructors planted the weathered bones in the wooded enclave's thick underbrush, just as wild animals might scatter the remains of a homicide victim.