Sam Johnson, my chief forensic investigator in Florida, was remarkable. Sometimes, he just knew.
He couldn’t say how he knew. He couldn’t explain what he looked for. But Sam was often able to differentiate at a glance a death scene that was genuinely suspicious for foul play from one in which the circumstances, setting or the position of the body was unusual but unrelated to criminal activity.
An ex-cop who had no medical training, Sam was also amazingly good at evaluating a dead body. I was sitting at a desk in the morgue one day, filling out paperwork before starting an autopsy. A bored assistant was standing next to the autopsy table labeling specimen containers. Sam, who’d just arrived for his shift, poked his head through the door and glanced at the body. “So,” he said. “Who killed this guy?”
I almost dropped my pen. The body had been found at a homeless camp in the woods. Police officers and another of my scene investigators thought he’d overdosed on alcohol, and that’s the kind of simple case I was mentally prepared for. When I’d casually glanced at the body as I walked into the morgue, I saw nothing suspicious. But Sam was right. When I undressed the man and examined him carefully, I found subtle indications that he’d been murdered.
What Sam saw from across the room I can’t imagine, and he couldn’t explain. “He just looks like it,” Sam said.
I’ve occasionally had gut feelings when dealing with the dead. Sometimes, it’s a sense of alarm – “there’s something wrong.” Sometimes, it’s a sense of reassurance –“this is nothing to worry about.” But my intuition isn’t nearly as well-developed as Sam’s. I can’t trust myself to “know” very much until all the evidence is in.
Daniel Kahneman, a psychologist who won the 2002 Nobel Prize in economic sciences, wrote about expert intuition in “Thinking, Fast and Slow.” Kahneman says intuition isn’t magic – it’s memory-enabled recognition.
A situation provides cues that direct the expert’s unconscious mind to memories of other situations. By scanning for pattern matches within those remembered situations, the expert can come up with answers that elude less experienced observers.
A 2-year-old who glimpses a dog and says, “doggie,” has correctly identified a complex pattern. Human brains learn recognition skills quite easily. In contrast, it’s an immense challenge to teach a computer to recognize as “dog” any image of any breed in any position taken from any angle.
For expert intuition to be at all reliable, Kahneman says, the situation must be “regular” – that is, orderly and subject to defined rules. Think dog anatomy, chess or fire behavior as opposed to stock markets or future world affairs.
Experts must learn a system’s regularities through prolonged practice –10,000 hours for many skills. Sam had investigated deaths for 20 years.
Quick feedback is key. Anesthesiologists find out very quickly if their interventions affect a patient for good or ill. Thus, says Kahneman, if an anesthesiologist says, “I have a bad feeling,” everyone in the operating room should prepare for an emergency.
I started the autopsy immediately and confirmed Sam’s hunch within the hour.
If Kahneman’s theory of expert intuition is correct, Sam has tens of thousands of images of death scenes and bodies stored in unconscious memory. He can scan those images almost instantly, compare them to a body in front of him and recognize clues invisible to others.
Such a skill seems a lot like magic.
Dr. Carol J. Huser, a forensic pathologist, served as La Plata County coroner from 2003-12. She now lives in Florida and Maryland. Reach her at firstname.lastname@example.org.