The first thing to disappear as a body deteriorates are the soft tissues. That's due to the growth of bacteria that escape the gastrointestinal tract and spread throughout the body after we die; after death, our immune mechanisms are no longer functioning to keep the bacteria contained in the intestine. And the most significant factor in determining how quickly the bacteria spread through the body is temperature: the higher the temperature, the faster the rate of decomposition of the soft tissue. So, when a body goes into water, the colder the water, the better the body's bacteria are contained. And the deeper down the body goes, the colder the water is. Once the body gets below the sun line - the point where sunlight no longer penetrates to a significant degree -- which may be about twenty feet in some places, ten feet in other places, the water stays around thirty-seven or thirty-eight degrees Fahrenheit. As you may remember from science class, a large body of water only freezes on the surface, not the bottom; so down where the Titanic is, the water never gets below about thirty-four degrees or so. At that temperature, bacteria can't function, so decomposition is markedly inhibited and bodies can stay in very good condition. At that depth, the bodies are affected largely by animal activity. If there are fish or eels or crabs, they can contribute to the destruction of the soft tissues. What often happens at depths below thirty to forty feet is that bacteria don't grow and if animal activity isn't a factor, the soft tissues can turn into a fatty substance called adipocere - also called "grave wax." The body can remain in this wax-like state for a long period of time.

But eventually, the soft tissues are lost. This may take a few weeks in warm water or years in cold water. And once the soft tissues are gone, the bones -- the skeletal structures -- are exposed and can remain intact for decades. In the salt water where the Titanic is, over time there would be slow chemical reactions by which the calcium would leave the bones and so the structure of the bones would gradually dissolve into the surrounding water. What's happened with the Titanic, given the length of time it was under water before being discovered -- somewhere around seventy-five years -- no bones, no bodies have been found. That's because they've essentially dissolved away as a result of chemical reactions, although very slowly because of the cold temperature.

In comparison, in the case of the crash of TWA Flight 800 off Long Island a few years ago, the bodies were a hundred feet under water. Except for some destruction of soft tissues resulting from animal activity, the bodies remained in excellent condition until they were discovered, because of the temperature of the water.

In what kinds of cases is cause of death the most difficult to determine?

In general, the most difficult cause of death to determine -- from a medical examiner's point of view -- are deaths from strangulation or suffocation. That's because these causes may not leave marks on the outside of the body. In shootings, stabbings, baseball bat injuries, deaths from automobile accidents, etc., there are clues on the outside of the body. But with asphyxia, i.e., a lack of oxygen getting to the body - and with poisonings as well -- there may be no clues on the outside of the body indicating that this may be an unnatural death, let alone a homicide. So those are the cases that require the most careful dissections, particularly of the neck organs. It's very important to look under the skin of the neck for small signs of trauma -- usually hemorrhage, sometimes fractures -- because they can easily be missed. There has to be a high index of suspicion when there's a suffocation death, when a person couldn't breathe, but there are no marks are left on the body.

Poisoning cases are difficult because there has to be suspicion on the part of the person conducting the investigation that indicates an autopsy should be done, and that proper tissues and fluids should be taken for chemical analysis. If those samples aren't taken, then the poison will be missed.

You said previously that the hyoid is not broken in all cases of manual strangulation. Can you give an estimate of the percentage of cases in which the hyoid is broken?

The hyoid bone is a little U-shaped bone just on top of the Adam's Apple. The Adam's Apple is thyroid cartilage and it forms the big part of the larynx. As we get older, our cartilage and the hyoid bone get calcified and manual strangulation is more likely to cause a hyoid fracture. When we're teenagers, both of these structures are very pliable -- like gristle -- and if a young person or child is strangled, they may not suffer a fracture of any of the bones of the neck. But above approximately forty years of age, the majority of manual strangulation cases will show significant trauma to the neck: hemorrhages around the windpipe and fractures of the hyoid bone or thyroid cartilage. Below age forty, when the those structures are not yet calcified, it's less than fifty percent of manual strangulations in which hyoid fractures occur.

Is it possible for a blow to the cheek to transect the left vertebral artery and cause death?

This was an issue in the recent "Hockey Dad" case, in which one of the dads died as the result of a laceration -- a tear -- of the vertebral artery. The issue of tears - transections -- of the vertebral artery comes up occasionally when, at the time of autopsy, the examiner finds a hemorrhage around the brain with no normal reason for the hemorrhage to be present. That is, there's no rupture of any of the blood vessels surrounding the brain, there's no tumor or traumatic injury that would have caused the hemorrhage. That situation requires the medical examiner performing the autopsy to closely examine the neck area.

Normally, the neck area -- which will show whether the vertebral artery has been torn -- is not inspected at a routine autopsy; the neck area is even more rarely inspected in a hospital autopsy conducted after a natural death. When we medical examiners are responsible for doing an autopsy because of the sudden death of an otherwise healthy person, we will occasionally look in the neck area -- when we see hemorrhage around the brain and there's no good explanation for it.

Vertebral artery hemorrhage can occur from a single blow that just happens to catch the side of the neck where the artery goes up toward the brain. Normally the vertebral artery, as it comes up from just above the heart, goes into the spine - it's protected by the spinal column. But there's one little area where the vertebral artery goes into the cranial cavity where it's unprotected. That unprotected area is where a sharp blow -- with a hand, a fist, or I've seen it with a rock that struck a man by chance -- can cause the artery to tear, resulting in rapid hemorrhage around the brain and rapidly leading to death. So the answer is, "yes."

I'm studying for my BSN, (Bachelor of Science in Nursing) specializing in death investigation. I was wondering whether you've encountered Forensic nurses being utilized in law enforcement.

Yes. The role of nurses in Forensic investigations is increasing. There are many areas in which Forensic Nurses can provide a unique expertise in the emergency room, evaluating persons who may have been raped, for example. Forensic nurses not only help in the collection of trace evidence that might be present, but also in talking with the victim and giving the victim solace and comfort - something that, unfortunately doctors tend not to have time to do. So forensic nurses are very valuable in certain clinical situations. Increasingly, Medical Examiner's offices are utilizing forensic nurses to go to crime scenes and participate in death investigation, because of special training that the nurses have had in examining dead bodies and talking to families. Another example of how forensic nurses can be utilized is a program in the Veterans Administration Hospitals. In that program, forensic nurses read patient records to see if anything has been done wrong, to see whether there's any chance that there might have been an unnatural cause of death that hasn't been suspected. So there are many different ways in which forensic nurses can contribute to forensic investigations. I think in the future they will become even more important, working alongside Medical Examiners and emergency room doctors.

One of the leaders in the field of Forensic Nursing is Forensic Nurse Virginia Lynch, who has helped develop the International Association of Forensic Nurses. In fact, the Association of Forensic Nurses is having its tenth anniversary meeting in October of 2002 in Minneapolis, Minnesota. The organization now has, I think, two thousand nurses. Virginia Lynch is a very enthusiastic advocate for this profession. She just returned from six months in Africa, where many countries are using forensic nurses because they can do a lot of the work that doctors don't have time to do, or aren't interested in doing -- and they do it better and cheaper. For anyone who's interested, the International Association of Forensic Nurses has a website at www.forensicnurse.org. I think that forensic nursing is a specialty whose time has come.

If you could affect one sweeping change in the way murder investigations are conducted in this country, what would it be?

I think that what has to be done in this country is to develop some kind of bully pulpit to improve murder investigations, because there are so many different systems -- half the country uses coroner systems, half have Medical Examiner systems. And most of the Medical Examiner jurisdictions don't have proper forensic pathologists involved; doctors who are not forensic pathologists do the investigations. I think to develop uniformity of death investigation procedures, we should have a voice in the federal government similar to the Surgeon General; like a "Medical Examiner General" who develops policies and procedures to improve death investigation from the medical examiner's point of view. What I'm referring to is how to improve the use of forensic sciences. Death investigation from the point of view of the forensic scientist and the medical examiner certainly needs more attention.

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