What An Autopsy Report Won't Tell You
Autopsies: We've all seen enough cop shows to know how they work, right? You've got the examiner wearing a white or blue medical frock thing, maybe a matching hat and mask, those disposable latex gloves, a clipboard and pen, the body, medical instruments, and David Caruso from "CSI: Miami" in the background slipping on a pair of shades while spouting a slick one-liner past the camera. And in the end we know everything about how the person died, right? Not quite.
Basically, examinations of dead bodies work in two levels: with or without an autopsy. Taking the Lancashire City Council as a good example, almost two-thirds of those who die do not require autopsies because 1) a family doctor can vouch for the likely cause of death, 2) there's no foul play suspected, and 3) we've got non-invasive methods of examining a corpse. Those methods not only include things like a visual assessment of the body but also technologically non-invasive methods like CT scans.
But if those procedures don't prove enough, or if there's suspicion of a crime, then we've got to crack the body open. As Johns Hopkins Medicine says, a trained pathologist is the best person to conduct an autopsy because that person has knowledge of bodily tissues, chemical substances, and so on. Ultimately, though, an autopsy might not answer every question. An autopsy can't tell us exactly how a crime unfolded, as The Columbus Dispatch says, and not even toxicological reports are consistent across people or without limitations.
Evidence vs. interpretation
At risk of getting too gruesome, let's use a stabbing to illustrate autopsy limitations. Imagine a police officer finds a body in an alleyway and the person has been stabbed about 20 times. Wounds found on the arms and hands indicate that the person was raising their arms to act in self-defense, as sites like Relentless Defense explain. Also, the high number of stab wounds might indicate that the crime was sex-related (i.e., jealousy, revenge, etc.), per the Journal of Forensic and Legal Medicine. That, however, is more of a deduction and belongs to the realm of criminal psychology. And how about the order of the wounds? Which one was first, second, third, fourth, etc.? Unless one particular wound connects to the presence of lots of blood — which a detective at the scene would have seen, not a coroner — there's no way an autopsy could answer such questions.
As for toxicological reports, Forensic Science Simplified explains both their complexities and limitations as related to autopsies. Because of the gap in time between death and autopsy, chemicals move around and the body breaks down. The liver, for example, might display the presence of drugs when none actually exist. The stomach can be a more reliable location for gathering information because its contents have yet to be processed by the intestines, bladder, etc., but such findings aren't foolproof. Hair, bones, and vitreous humor in eyes can also provide toxicological data — but require highly skillful interpretation.
Cause vs. manner of death
On a whole, it should be clear by now that autopsies don't spill the beans on absolutely everything that happened to a person leading up to death — they just provide facts regarding the state of a body at the time of examination. Those facts might compose a portrait of how a person died, but such a portrait requires a deft interpretive hand. In the case of a crime or suspected crime, this is where a forensic pathologist steps in. As the University of New Mexico School of Medicine explains, such a person is trained to view autopsies through the lens of law enforcement and knows about ballistics, trace evidence (evidence passed from one source to another), forensic serology (examining bodily fluids like semen and blood), DNA analysis, and more.
In this way, autopsies might provide us with a cause of death, but not a manner of death. Pathology Outlines explains the difference. Maybe the cause of death was a blood clot in the brain, or a puncture wound to the aorta. The manner of death, though — natural, homicide, accidental, suicide, or undetermined — is trickier to figure out. If a blood clot in the brain caused the death, what caused the clot? Was it poison? If so, was it a suicide or a homicide? If an aorta was punctured, was it accidental, like from a car accident? Or, was it undetermined? Such questions illustrate that while autopsies are invaluable tools, they have limits.