MONTROSE – Contrary to Perry Mason thrillers on television, forensic pathologists are not supermen who can determine precisely the time, manner and cause of death and pinpoint likely suspects in all cases of foul play, according to Dr. Thomas Canfield of Montrose.
Canfield is a forensic pathologist who handles about one autopsy a week for Western Slope Police agencies. He did the autopsy on the body found in the Gunnison River Sept. 26.
Canfield said it will probably be two weeks to several months before the body is identified – and it may never be. This is often the case with unidentified bodies, he said.
“There is no urgency in a case like this; the urgency is in proceeding carefully and doing a good job,” the doctor said.
The major time lag is not in the autopsy itself, but in obtaining records, Canfield said. Dental charts are a good starting point, but possible victims must first be identified and their charts obtained for comparison. The same applies to medical histories of disease, birth defects, broken bones or other identifiable features, such as fingerprints.
“For example, did a possible victim have a fracture of the little toe?” Canfield said. “If we know that, we’ll carefully X-ray the little toe. Otherwise, I might miss it.”
Canfield said the autopsy itself usually takes only six to eight hours, but may be followed up later by more tests if other data warrants it. A good autopsy will usually provide definite clues as to the cause of death and, possibly, the manner – knife, gunshot wound – but does not provide identification.
He said it is possible to determine time of death within a few minutes – if a body is found within a few hours, and he knows all the environmental considerations, such as temperature and humidity.
Estimating time of death from the body found in the Gunnison cannot be more accurate than within a week or more, he said, because he did not know how long it was in the water, how much was exposed to the sun, what temperatures and wind effects were or how much decomposition was caused by animals, fish or insects.
Wounds will decompose faster than other tissues, but most gunshot wounds can be determined by bone damage or the nature of the tissues or by finding a bullet. Knife wounds can be determined “more often than you think you can,” he said.
Drowning can be determined in many cases, “but the degree of certainty changes with the degree of tissue change,” he said.
How is the autopsy itself conducted?
“Well, the first thing I do is, I do nothing,” Canfield said. “Then, I proceed very slowly.”
He said the body is frozen or chilled in almost all cases, because it gives some time for police data to be obtained for comparison with the body. It also stops the decomposition process and makes working with the body much easier and less distasteful.
Another advantage of freezing, he said, is that it kills or puts bacteria and waterborne animal life, such a leaches, in suspended animation. By consulting experts in the field, the lifecycles and types organisms found can give clues to how long the body has been dead.
Canfield very carefully documents everything he does, both in writing and photographically, in anticipation that the evidence will be needed in court.
The body is X-rayed from many angles to show old and new fractures, dental work, items imbedded in it or signs of sudden death. Also looked for are such things as pierced ears, contact lenses, and clothes.
One good clue might be a hairless ring on the calves of a male body. That means the man wore western boots while alive, Canfield said.
In many cases fingerprints can be taken. Sometimes paraffin and other chemicals can be used to amplify the characters of decayed prints, he said. One problem is that few women have been fingerprinted for record purposes, he noted. So comparisons are sometimes unavailable.
Age is determined by Canfield from bones, teeth and internal organs.
Poisons can sometimes be detected by toxicology tests that are routinely run on samples of bones, tissue and organs. Arsenic, for instance, has been found in bones of European notables who died hundreds of year ago. However, short-lived poisons dissipate quickly. Especially as bodies begin decaying, he said.
The microscope is used extensively in autopsies, particularly for examining body tissue. It can often reveal whether an injury was received before or after death – a critical point if the pathologist ends up testifying in court.
Once all this is done, the pathologist usually confers with consulting experts in the various fields – dentists, for example, to compare dental charts with X-rays of the body’s teeth – and an opinion is give[n] to the agencies involved.
“One thing people should keep in mind, is that time between death and autopsy directly affects what we can learn,” Canfield said.
He added, “In cases like this body in the river, I don’t have all the answers they want. There are limits on my capabilities, and limits on the development of the science. I may very well end up saying, ‘I have no opinion,’ or ‘I cannot determine’ the answers.”