by D P Lyle
Does a Cold Room Delay Detection of the Odor of Body Decomposition?
Q: My scenario is as follows: A mystery writer comes home from a luncheon, has a nap, writes until bedtime, goes to bed, gets up the next morning, and works until lunch-
time, when the police arrive at the door. They are looking for her husband (a cop), with whom she hasn't lived for seven months; he didn't show up for duty the night before. The officers discover him dead in the den. The door was closed, and the air-conditioning has been on. These are my questions: Would the smell of the decomposing body be prevalent in the house after twenty-four to thirty-six hours? Is it plausible that the writer wouldn't know that the corpse is in the closed-off room?
A: The short answer is yes.
Body decomposition begins immediately after death. Bacteria, both external and those that live within the intestine, go to work on the tissues, and under normal circumstances the smell of rotting flesh is apparent in twenty-four to forty-eight hours. This timeline depends on many things, particularly the ambient temperature. A warm environment quickens bacterial growth and thus the process of decomposition (like an incubator), while a colder one slows it (like a refrigerator).
If the room is warm, the odor of decomposition may appear in twenty-four hours or less; if cool, due to a low outside temperature or from air-conditioning, it may take three or four days or more. In this case your timing would work out. The AC would slow the process, and the closed door would help contain the odor.
How Long Does It Take for an Unburied Body to Skeletonize?
B: My question is about a character who is killed and left unburied in the elements during May in the mountains of the Northwest. The area has had an early spring, with warm days and cool nights. Along with the usual animal population there are bears and big cats.
How much decomposition would take place in four to five weeks? I know the bones would be scattered and hair would still be present. Is it possible the bones would be relatively clean in that amount of time?
A: The time required for skeletonization of a body varies greatly and depends on many factors. In your scenario the factors that would favor rapid loss of tissues would include the following:
The warm weather, which hastens bacterial-mediated decomposition
The body being unburied and exposed to the air, weather, bacteria, and predators
The length of the exposure
It is likely that after four or five weeks only skeletal remains, teeth, and hair would be found. And as you noted, some bones might be missing altogether, and others could be spread over a wide area as predators carried them away.
What Is Calor Mortis?
Q: What is calor mortis? The color of the body after death? Does the body change color after death?
A: Calor mortis is a rarely used term that does indeed refer to the postmortem color of the body.
At death, cardiac function ceases, and the blood stagnates and settles according to the dictates of gravity. This results in postmortem lividity, which becomes fixed in six to eight hours. This is a bluish, grayish, purplish discoloration of the tissues in the dependent areas.
The remainder of the body takes on a pale, waxy, or rubbery
appearance. The acral areas (toes, fingers, ears, and sometimes the lips) may retain a slight bluish hue. Occasionally, the entire body has a very faint bluish or even a yellowish tint.
The term "calor mortis," which I could find little reference to in the medical literature, seems to mean this overall change in color, not the areas of lividity for which the term "livor mortis" is sometimes used.
Under What Circumstances Is Body Mummification Likely to Occur?
Q: In the book I'm writing, someone finds the mummified remains of a child who had disappeared ten years earlier. Where would be the best place for the body to be discovered so that the mummification would be realistic?
A: The preservation of an intact body can occur under varying circumstances. Freezing, in areas of permafrost, has preserved bodies for hundreds and even thousands of years. The same can be said for peat bogs. A bog is a wet, spongy, typically low-lying area that is composed chiefly of peat and sphagnum moss. It is typically acidic, and bodies that have sunk into the bog are spared bacterial degradation and may be well preserved when discovered years later.
But true mummification requires a dry climate. It can be either cold or warm, but it must be dry, preferably though not necessarily with a moving air current. It is desiccation (drying out or dehydration) of the body that leads to mummy formation. Also, the lack of moisture does not favor bacterial growth so that decomposition is halted or slowed.
As the corpse dries out, the muscles, organs, and skin shrink and
become dark brown or black and leathery in quality. Depending on environmental conditions, this process may take several weeks or months. Once established, the mummified corpse can remain intact for years or decades.
As far as location of the corpse is concerned, any place that is dry, sheltered from the weather, and protected from predators would work. An attic, basement, or crawl space in a house or other structure can supply the right conditions. Desert burial can also.
Another possibility for long-term preservation of a body is adipocere formation. Adipocere is a waxy substance derived from body fat, and it was first described by Antoine Fourcroy in 1789.
The formation of adipocere is an alternative to complete putrefaction of the body. In reality, both putrefaction and adipocere formation begin in most corpses. If environmental factors favor bacterial growth and thus putrefaction, the body will deteriorate; if they inhibit bacterial growth and favor adipocere formation, the body will be preserved. In some cases the corpse does both so that part of the body is preserved and part is destroyed.
Adipocere formation requires certain conditions. If the body is buried in damp soil, immersed in water, or placed in a crypt or vault, adipocere can result. The key here is that moisture is required. Under these circumstances the anaerobic (meaning it doesn't require oxygen to grow) bacterium Clostridia perfringens (the same culprit that produces gas gangrene) goes to work on the body, producing lecithinase, an enzyme that causes hydrolysis and hydro-genation of the corpse's fat. The result of this action is the formation of adipocere.
Adipocere is a waxy substance that varies in color from white to pinkish to gray or greenish gray. It takes three to twelve months to form and may last for decades, though it tends to become more brittle as the years pass.
The importance of this process is that instead of the usual dissolution of the tissues by the putrefaction process, the formation of adipocere casts the body permanently in its postmortem shape.
Some facial features and knife or bullet wounds may be well preserved. Basically, the corpse looks like a wax doll.
Either of these types of mummification should fit your needs.
Is It Possible to Obtain Fingerprints from a Mummified Corpse?
Q: Can fingerprints be obtained from mummified remains?
A: Sometimes. It depends, of course, on the degree of deterioration that the body has undergone. Typically, in well-preserved mummified corpses, the fingers are dark, shriveled, and leathery. Soaking them in a 20 percent acetic acid (the acid found in vinegar) solution for twenty-four to forty-eight hours may swell them to normal size and reveal the finger pad ridges. Glycerin has been used for the same purpose. One novel method that has worked is to cut away the skin of the finger pad and press it flat with a level or cylindrical metal object. This may also expose the ridges.
Does a Body Mummify If It Has Been Bricked into a Wall for Several Years?
Q: What would the corpse of an average-sized young woman look like after being bricked up in an alcove of a house for several years? The space is in the interior of the house and is dry and has no openings (although, of course, no space is truly airtight). The house is in the Lake District of England, it's unoccupied, and it is neither cooled in summer nor heated in winter. Would the body mummify, or
would all parts except the skeleton decompose? When a body mummifies, do the eyeballs dry out, shrink, and sink back into the sockets?
A: Either mummification or skeletalization could happen. If the ambient air is humid, such as near the seacoast, skeletalization would likely occur. The humidity would favor bacterial growth and putrefaction of the tissues. But if the air is dry, most likely the body would mummify. The skin would desiccate (dry out), become dark brown or black, take on a leathery consistency, and shrink onto the skeleton as the muscles and internal organs also desiccated—like shrink-wrap. The entire corpse would appear small, and the arms and legs would likely contract into a fetal position if the space allowed.
Yes, the eyeballs would shrink down to nothing or perhaps a pea-sized hard knot that wouldn't be readily visible. The eye sockets would appear empty or caved in.
While either could occur, a mummified body is much more visual and spooky.
Will a Body Encased in Concrete Mummify?
Q: I want a victim's body to be found four years after his death by gunshot wound. Right now I have the body unearthed when a fire destroys a building whose foundation was laid four years earlier. The building burns down to the foundation, and the body is found while workers are clearing the lot and digging up the remaining concrete. What state would the body be in at this point? Mummified? Could he be identified? Also, at the time of the murder, I haven't figured out how to get the body into the excavation prior to the concrete being poured without someone noticing.
A: The body could be either skeletonized or mummified. If the latter, it would likely look dark and leathery. Identification might
depend on dental records and possibly fingerprints. There are techniques for recovering prints from mummified remains.
The bullet could be within the mummy or nearby even if skeletonized. Maybe a fractured or nicked rib or other bone plus a bullet fragment would be the tipoff and lead the M.E. to determine that a gunshot was the cause of death.
If the body is buried beneath concrete, mummification becomes more likely since less oxygen would reach the body, and decomposition would thus be slowed or halted. Also, animal predation and the effects of weather would be absent.
Depending on the size and depth of the excavation, the body could be partially buried (actually, a simple soil covering would suffice), and those working the cement truck wouldn't notice a slight bump in the floor of the trench dug for the foundation.
Is It Possible to Trick a Lie Detector?
Q: In mv story I want the murderer to undergo a lie detector test and pass it even though he is guilty. Is it possible to trick a lie detector machine? If so, how?
A: A lie detector (polygraph) examination is not an exact test, and for this reason it is not typically admissible in court. Law enforcement uses it primarily to narrow the focus of their investigation by excluding some suspects. Though not completely accurate in this regard, it does help at times.
The polygraph ("poly" means many; "graph" means to write) tests several of the body's responses to stress. It consists of a blood pressure cuff, a chest band to measure respiration, a skin electrode that measures the galvanic (electrical) skin response, and a recording device to collect the data. Under stress the blood pressure and heart rate increase, as does the depth and frequency of respiration, and sweat leaks from the pores. The electrolytes (sodium, potas-
sium, and chloride) in sweat increase the electrical conductivity of the skin. This is called the galvanic response. The examiner looks for stress-induced increases in each of these parameters as a clue to likely deception.
During the pretest interview, the examiner asks questions to determine if the individual has any illnesses or psychiatric disorders or is taking any medications that might interfere with these responses and thus invalidate the test.
The easiest way to defeat the test is to make it inconclusive—that is, one in which the examiner is unable to discern if deception is present or not. People who are histrionic or subject to extreme nervousness or panic attacks are difficult if not impossible to examine. Faking a histrionic reaction may invalidate or confuse the results.
During the test the examiner asks some questions that are low stress and easy to answer truthfully: Did you have eggs for breakfast this morning? Do you live at 123 Elm Street? Simple and non-stressful. He intersperses questions that are more stressful or more directly related to the crime in question: Did you have a confrontation with Mr. Jones? Were you at his home on the evening of June 3? Did you kill Mr. Jones with a hammer? A truthful person will react the same to these questions, while the guilty party will become stressed when answering the pointed questions. A high-strung individual might react regardless of the benignity of the question. He would panic at everything so that his blood pressure, heart rate, respiration, and galvanic skin response jump if someone says, "Boo."
Forcing a panic-like response to every question could cloud the deception and make the test inclusive. The killer could purposefully tighten his muscles, breathe more deeply than usual, concentrate on anything stressful, even his own guilt, regardless of the question, or even put a tack in his shoe to step on after each question. The examiner might not be able to tell the difference between these forced stresses and the real stress of lying.
The other option would be to go the other way—that is, remain
calm throughout. Some sociopaths simply don't feel guilt the way normal people do. Though not common, they may be naturally able to defeat the test because they don't feel guilty. Or your perp might employ certain relaxation techniques to blunt the stress responses. Biofeedback, imagery, breath control, and other meditative techniques might work. Or he could use drugs. Alcohol, narcotics, and other sedative substances might help if he can act sober enough to take the test in the first place.
Another choice might be the group of drugs we call beta-blockers. Common ones are Inderal, Tenormin, and Lopressor. Taking 10 milligrams (mg) of Inderal or 25 to 50 mg of Tenormin or 50 mg of Lopressor an hour or two before the test might do the trick. These drugs block the effect of adrenaline on the cardiovascular system. They decrease the blood pressure and slow the heart rate. They also have a calming effect on the brain and may lessen stress-induced sweating. Thus, they might blunt the stress responses enough for the perp to "pass" the test.
Can an Intoxicated Person Fake a Field Sobriety Test?
Q: My character is intoxicated when he must rush to the rescue of a loved one. His speeding car is stopped by the police. It's a long story, but there is no way he can explain his situation to the police in any believable fashion. Is it possible he could fake a field sobriety test or a Breathalyzer or blood test for alcohol intoxication?
A: Tricking a Breathalyzer or a blood alcohol test is virtually impossible. They are accurate, and you can't hide the alcohol in your bloodstream or on your exhaled breath.
Passing a field sobriety test while intoxicated is very difficult. The reason for this is that alcohol affects the cerebellum of the
brain, which controls balance, gait, movement, and coordination. The field tests are designed to evaluate cerebellar function, which in the presence of alcohol is abnormal.
Standing with your eyes closed, arms spread to the side, or on one foot leads to swaying and perhaps falling. Walking a straight line, heel to toe, becomes a wavering, wandering stroll. Touching your finger to your nose results in poking your eye. And looking to the side while facing straight ahead causes the eyes to bounce laterally. (This is called nystagmus.) Regardless of how hard you concentrate on these tasks, the alcohol-soaked cerebellum will prevent performance in a normal fashion. Book him, Dano.
Can Fingerprints Be Lifted from Human Skin?
Q: Can fingerprints be lifted from human skin—for example, from the neck of a victim who was manually strangled? How long after death do the prints remain detectable?
A: The short answer is yes, but the window of opportunity is very short. It depends on many factors, but prints have been lifted from s
kin and used in identifying perps. On living flesh they last about sixty to ninety minutes. On corpses it is a little longer, depending on environmental conditions. The sooner the prints are collected, the better.
There are several techniques for lifting prints from skin.
The Kromekote Technique: A Kromekote card is pressed over the suspected print (unexposed Polaroid film may also be used), and then it is dusted with black print powder to expose the print. The print is then photographed and finally lifted with cellophane tape.
The Magna-Brush Technique: The body or body part is brushed with MacDonnell Magna Jet Black Powder (which is actually extremely fine iron filings), and any prints that appear are pho-
tographed. Typically, a light is directed toward the print from whatever angle exposes the ridge details best.
Electron Emission Radiography: The skin where the suspected print is located is dusted with a fine lead powder and then examined by X ray. The bulky size of the X ray equipment limits the usefulness of this technique, however.
Iodine-Silver-Plate Technique: The suspected area is exposed to an iodine vapor, which is absorbed by the moisture in the latent print. It is then dusted with a silver powder that reacts with the iodine to form silver iodide. This compound darkens when exposed to intense light (silver iodide is a component of photographic film), and the print becomes visible. Alternatively, the iodine fuming may be followed by an application of alpha-naphthoflavone to reveal the ridge pattern.
Cyanoacrylate Fuming: After the application of this substance, the latent print appears white, which may be difficult to see and photograph on light skin. To make it more visible, the fumed prints are colored with various biologic stains, commercial dyes, or TEC (Europium ThenoylTrifluoroAcetone ortho-phenanthroline or EuTTAPhen or simply Europium complex, for short). The result is best viewed under an alternative light source such as an ultraviolet light.
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