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Category Archives: Time of Death

Can Odor Reveal the Time Of Death?

One of the most important determinations that the medical examiner must make in any death investigation is the Time Of Death (TOD). This alone might help solve a homicide. Who had the motive, means, and opportunity? The time of death relates to the opportunity. If the death occurred while the primary suspect was in another state or had a solid alibi, then he moves down the suspect list. On the other hand, if the TOD was determined to be a time frame where he was in the neighborhood, then he remains a viable suspect.

The ME uses many techniques to help estimate the TOD. Check out this ARTICLE for a brief overview of these techniques. One of the methods he employs is the degree of decay that has occurred. He must take into account the environmental conditions near the corpse and then must make a best estimate as to how fast the decomposition process would have advanced under those conditions. This is always a best guess, as is the case with each of the techniques he employs.

When a corpse decays it undergoes a chemical decomposition and this process releases many volatile organic compounds (VOCs) into the surrounding air. These compounds are at least partially responsible for the odor of decay and they tend to be released in a predictable pattern as the decay process progresses. What if these VOCs could be sampled and used as a more scientific method for determining the Post Mortem Interval (PMI)? That is, the time since death.

Research is currently underway to assess this technique. Using the combination of gas chromatography and mass spectrometry (GC/MS), researchers have found that these volatile chemicals can be trapped and analyzed. Hopefully this technique will prove to be useful in narrowing down the TOD. We’ll see.

 

Gas Chromatograph

Gas Chromatograph

 

 

 

Crime and Science Radio: Dealing With the Dead: A Life in the Morgue: In Conversation with Dr. Cyril Wecht

Join DP Lyle and Jan Burke as they welcome Dr. Cyril Wecht, internationally renowned forensics pathologist Dr. Cyril Wecht as we discuss his life in criminal justice and the numerous famous cases he has been involved with over his stellar career.

BIO: Dr. Cyril Wecht holds degrees in both medicine and law, receiving his MD degree from the University of Pittsburgh and his law degree from the University of Maryland. He holds professorships at the University of Pittsburgh and Duquesne University School of Law. He has published nearly 600 scientific articles, is on the editorial board of more that 20 medical-legal and forensic scientific publications, and had published several books on forensic science. His list of famous cases is a who’s who in medical-legal investigation.

 

CYRIL-WECHT

LISTEN: http://www.blogtalkradio.com/suspensemagazine/2014/03/07/crime-and-science-radio-with-special-guest-cyril-wecht-md

LINKS:

Dr. Wecht’s Website: http://www.cyrilwecht.com

Dr. Wecht’s books and videos: http://www.cyrilwecht.com/books.php

50 Years Later, Wecht Continues To Poke Holes in Report on JFK Assassination: http://triblive.com/news/allegheny/5017529-74/wecht-commission-specter#axzz2tuBTchS1

Dr. Cyril Wecht Believes Killers of JFK, RFK, MLK Had Help: http://www.vindy.com/news/2013/may/01/renowned-pathologist-makes-a-case-for-co/

Dr. Cyril Wecht Lectures on the JFK Assassination: https://www.youtube.com/watch?v=-muQL-QPKeM

Dr. Cyril Wecht on JFK Assassination: Let’s Uncover the Truth: https://www.youtube.com/watch?v=YtUL-BpZAu8

Crime Library: JonBenet: From Impressions To Book by Dr. Katherine Ramsland: http://www.crimelibrary.com/criminal_mind/forensics/cyril_wecht/6.html

Dr. Cyril Wecht Discusses Forensic Challenges of Cold Cases: http://www.wtae.com/news/local/allegheny/Dr-Cyril-Wecht-discusses-forensic-challenges-of-cold-cases/19648550

Dr. Cyril Wecht: The Benefits of Forensic Credentialing: http://www.pbs.org/wgbh/pages/frontline/criminal-justice/real-csi/dr-cyril-wecht-the-benefits-of-forensic-credentialing/

Cyril H. Wecht: What I Know: http://www.pittsburghquarterly.com/index.php/What-Do-I-Know/what-do-i-know-with-cyril-h-wecht.html

Dr. Cyril H. Wecht: Pittsburgh’s Polymath: http://www.popularpittsburgh.com/pittsburgh-info/pittsburgh-history/famous-pittsburghers/dr-cyril-wecht.aspx

 

Final-Exams

 

 

 

 

 

Bacteria and Time Of Death

bacteria1

 

 

One of the most important things the ME must determine in any death investigation is the time of death. This determination can support or destroy alibis and suspect and witness statements, and point the finger at certain individuals while directing it away from others.

The ME uses various techniques to make his “best guess” as to the victim’s time of death. Things like body temperature, rigor mortis, lividity, stomach contents, and a few other determinations. Unfortunately, most of these are only marginally accurate.

Here is an article I wrote on this subject: http://www.dplylemd.com/DPLyleMD/Art-Timely_death.html

Any tool that can help make this assessment more accurate would be welcome.

Researchers at Sam Houston State University’s Department of Biological Sciences are looking into just such a tool. Bacteria. Just as insects visit a corpse in a more or less predictable pattern, it seems that bacteria do also.

We’ll see how this pans out but it’s very interesting.

 

 

Q and A: How Would the Time of Death Be Determined in a Corpse Found in Snow?

Q: In my story, the body of a young woman is found by cross-country skiers in high-mountain country. (Average temps in December: 20 degrees/low to 40 degrees/high;  elevation about 9000 ft.) If the person had been dressed in heavy clothes, and the body had been there about 24 hours, would it be completely frozen? Partially? Would there be any way to determine when death had occurred?

MT, Albuquerque, NM

Jack-Frozen

A: The corpse would be at least partially and could be completely frozen–perhaps with some of the deeper internal organs only partially frozen. It depends on the clothing, exposure, moisture, wind, etc. Also the old rule that whatever happens, happens comes into play here. So the freezing could be either complete or partial.

Under these conditions, rigor and lividity would be delayed to an unpredictable degree so these would be very crude indicators and not very useful in determining the time of death (TOD). Body temperature might be more useful—emphasis on might—but this would not be very accurate either. If the core body temp had reached the ambient temperature, this determination is of no use, since once the corpse reaches the ambient temperature it will remain stable at that temperature, making body temperature useless. For example, if the corpse reached the ambient temp after 18 hours then 24 hours would look like 36 or 48 as far as body temp is concerned.

But if the corpse hasn’t reached ambient temperature, core body temp can be used to estimate the TOD. Not very accurately but at least in the ballpark. Under “normal” circumstances, a body loses heat at about 1.5 degrees per hour, but this depends on many variables. Your scenario is definitely not “normal,” so temp would be lost more rapidly. Could be 2 or 3 or 4 degrees per hour if there is wind or cold rain for example. Let’s say the ME found the core temp was 40 with an ambient temp of 30. This means the body is still cooling since it has not yet reached ambient temperature. Let’s also say that in his experience he believes (educated guess at best) the body would lose about 3 degrees per hour under the circumstances he sees at the scene. If so, subtracting the measured corpse temperature (40 degrees) from the normal body temperature (98) and dividing by the rate of loss (3 degrees/hour) would yield the estimated TOD.

The math: 98-40 = 58; 58/3 = 19 hours.

Based on these calculations, your ME might conclude that the death occurred approximately 19 hours earlier, give or take a couple of hours.

Of course the major flaw here is that the actual rate of temperature loss might vary from his estimate so, despite the math, his assessment remains a best guess. He would likely suggest a broad range—maybe saying the TOD was between 16 and 24 hours earlier. That’s really the best he could do.

So your corpse could be partially or completely frozen and the time of death could be difficult to determine. Except for one more trick: stomach contents.

Let’s say the corpse is frozen so that temp, rigor, and lividity are of no help yet it was known that the victim had eaten a certain food at a certain time prior to his disappearance. It takes the stomach 2-3 or so hours to empty after a meal so if the ME found the undigested meal in the victim’s stomach and knew the time of this final meal from witnesses, he could then more accurately place the time of death as within 2-3 hours after that meal. Let’s say he had lunch around noon, went skiing, and was then found dead 24 hours later. If the ME found that last meal still in his stomach he might suggest that the TOD was between 1 and 4 p.m. the day before. This might be your best bet for narrowing down the TOD.

 
 

Crime & Science Radio: The Body Tells the Tale: DP Lyle and Jan Burke Interview Dr. Bill Bass and Jon Jefferson

CSR 300x250-72dpi

The Body Tells the Tale: DP Lyle and Jan Burke Interview Dr. Bill Bass and Jon Jefferson

Join DP Lyle and Jan Burke as they explore the world of death, corpses, and decay with Dr. Bill Bass and Jon Jefferson. Dr. Bass is the founder of the University of Tennessee Anthropological Research Facility, the so called Body Farm. Jon Jefferson is a journalist, writer, and documentary film maker. Together they write fiction as Jefferson Bass. This will be a lively, or is it deadly, interview.

LISTENhttp://www.blogtalkradio.com/suspensemagazine/2013/11/20/crime-and-science-radio–jon-jefferson-and-bill-bass

LINKS:

The Body Farm-Wikipedia: http://en.wikipedia.org/wiki/Body_farm

Tour The Body Farm: http://www.jeffersonbass.com/videos.html

Video Tour of The Body Farm: http://www.youtube.com/watch?v=GSDCiOW81mk

WBIR Interview: http://www.wbir.com/news/article/139066/190/Your-Stories-Dr-Bill

JeffersonBass Website: http://www.jeffersonbass.com/index.php

Death’s Acre: Inside the Legendary Forensic Lab the Body Farm Where the Dead Do Tell Tales: http://www.amazon.com/Deaths-Acre-Inside-Legendary-Forensic/dp/0425198324

Metro Pulse: The Cult of Forensics Expert Dr. Bill Bass: http://www.metropulse.com/news/2009/feb/25/cult-forensics-expert-dr-bill-bass/

Peter Breslow’s 2004 NPR Profile of The Body Farm: http://www.npr.org/templates/story/story.php?storyId=1906569

Taphonomy-Wikipedia: http://en.wikipedia.org/wiki/Taphonomy

 

Bloodstain Camera Finds Blood Quickly and Efficiently

Detecting blood at a crime scene is often essential for determining if a crime did indeed occur and how the act unfolded—crime scene reconstruction. At the scene, a meticulous search for blood can be tedious, time-consuming, and eat up many man-hours.

 

Techs search for bloodstains

Techs search for bloodstains

 

Shed blood is not always obvious. The stains are not always patent (visible) but rather latent (invisible). The standard in such situations has been to employ Luminol, which can find even very small latent bloodstains. But Luminol takes time and requires darkness—not always obtainable, particularly in outdoor, daytime crime scenes.

 

Luminol helps expose latent bloody shoeprints

Luminol helps expose latent bloody shoeprints

 

A new technology developed by Dr. Meez Islam and colleagues at Teeside University promises to not only be able to detect latent blood spatters quickly but also age the blood very accurately. With month-old stains the device, which uses hyperspectral imaging, can narrow its deposition down to a day and with fresh blood down to an hour. This should greatly help with Time of Death determination—-or at least the time when the blood was shed.

 

Fresh blood spatter

Fresh blood spatter

 

Blood exits the body bright red but with time and oxidation becomes rusty brown and does so along a predictable timeline. Accurate determination of the bloodstain’s color with hyperspectral imaging reveals its approximate age.

Very cool. And potentially very useful.

 

Q and A: Can My Villain “Force Feed” Pills To a Dead Woman?

Q: My hero, an investigative journalist, is looking into the death of a woman at an acid house/rave party in the early 1990′s. The novel is set in the present day and so the hero has no access to the body, just autopsy reports, coroners reports, the transcript of the inquest, etc. The woman was a light user of Ecstasy but the autopsy discovered that she had 70 ecstasy pills in her stomach. The scenario I want to create is that the hero discovers that while the woman took some of the pills willingly, she was then force fed others, and then after she died she was force fed yet more. In order for this scenario to work I’m wondering the following:

1) For how long after death does stomach acid continue to operate?

2) For how long after death would the digestive system continue to break down the ecstasy and would the ecstasy continue to be absorbed into the bloodstream?

3) Is it likely/possible that a sizeable amount of pills would remain undigested in her stomach, bearing in mind that the body was not found for a number of hours?

4) What injuries/signs on the body would there be of someone force feeding her the pills?

5) Is it possible to force feed somebody pills after death, how would they get the corpse to “swallow” and what injuries might be caused to the body as a result?

James, St Albans, UK.

 

PIlls

 

 

A: At death, all metabolic processes cease immediately since there is no longer blood flow to keep these processes going or even to keep the tissues and cells responsible for these activities alive. This includes the digestive processes. Sure there could still be a small amount of acid effect but this would only be from the acid in the stomach at the time of death and this would be quickly neutralized by the materials the acid was combining with. The bottom line is that all digestive processes cease immediately on death, more or less freezing the stomach contents in time. This is also true for the level of most toxins in the blood and urine, which offers the medical examiner a tool for determining the cause and time of death.

At death, the stomach would no longer move or churn or secrete acids and digestive enzymes so the ecstasy would remain intact as it was at the time of death. Yes there could conceivably be residual whole pills and in fact this is not uncommon in overdoses of all kinds. Some dissolve and are absorbed prior to death and others do not and these remnants can then be tested to determine what they are. All the stomach contents would remain intact until the decay process destroyed them, so if the body was found in a reasonable period of time, the stomach contents could be analyzed for their chemical characteristics, which would include the presence of any drugs or alcohol.

It is very difficult to force-feed a living person pills and so doing could lead to trauma around the mouth and face as the pills were shoved into the victim’s mouth and his mouth and nose held close until he swallowed. Or there could be no trauma and in which case there would be no way of knowing this. But evidence of trauma might suggest a force-feeding. It would be a best guess but an experienced medical examiner can usually make this determination. Since all processes and movement by the deceased stop at death, swallowing cannot occur and force-feeding a corpse is impossible. The pills would simply collect in the mouth and throat.

In your victim there could easily be undigested pills and toxicological testing of these, and of course blood and urine, would reveal what chemicals were in the victim’s stomach and system. Since your body is found several hours later there would be essentially no decay and therefore everything in the bloodstream and in the stomach would remain intact more or less as it was at the time of death. With facial trauma the ME might consider that the OD was forced, and in the absence of such evidence might simply think it was an intentional or accidental OD.

Also this ARTICLE on my website might help.

 

Q and A: Can My ME Determine If a Child Died From Exposure As Opposed To Being Locked in a Heated Vehicle?

Q: In my story, a police officer is on the scene where the body of a 3 year old child was found among the rocks and weeds of a dried up riverbed in Southern California. It is early summer. Can the CSI techs or the ME determine if the child died from being locked up in a heated car rather than from exposure to the elements where the body was found?

Jack Dietz, Production Coordinator, Las Vegas, NV

A: The simple answer is that this is not very likely however there might be a way. Much depends on the condition of the body. If it is severely decayed or has become skeletal, the ME would have little to work with and there would be no way to determine exactly where the death occurred. In either case the death would be from that catchall term “exposure.” What that means is that the victim died from lack of water or food, with water of course being the most important. Exposure deaths are almost always due to severe dehydration.

However, if the child is found within a day or two of death, the body would be more or less intact and the ME might be able to estimate where the death had occurred, given the two choices you outlined. One difference would be insect activity. If the child died in the trunk as opposed to being exposed outdoors there would be less insect activity for the amount of time since death than would be expected from an exposed corpse. If the ME determined that the child had been dead for 2 or 3 days yet there was essentially no insect activity, it would mean that she had been in a protected environment, such as an enclosed car or car trunk, for those 2 or 3 days and only exposed for maybe a few hours. On the other hand, if he found insect activity that matched his estimate of the time since death, this would favor her being in an exposed environment for those 2 to 3 days. It’s not that flies can’t get into car trunks, it’s just that most trunks are so well sealed, fly access would be very limited, if at all.

On a similar note, predatory animals would not be able to attack the body while it was in the car but if exposed predator feeding on an exposed body is fairly common. Coyotes are everywhere. Predator activity would suggest a longer period of environmental exposure.

fiberanalysis2

 

One circumstance that might be interesting for you would be if the child died in either the trunk or on the floorboard of the car. As she died from hyperthermia and dehydration, she would increasingly gasp for breath toward the end of her life and could inhale carpet fibers from the trunk lining or floor carpets. This would not happen if death occurred while exposed outside. This would of course require that the body be in fairly good condition. I think as long as you have the body found within a few days, the decay process would not have progressed far enough for the lungs to be destroyed and the medical examiner might see these fibers during his microscopic examination of lung tissue. Once he found these fibers, he would know that the victim had inhaled them and therefore was alive while in the car. So finding the fibers would at least allow the medical examiner to guess that she had been in the car near or shortly before her death.

fiberanalysis

 

Another interesting thing about this scenario is that the ME could then analyze these fibers physically, optically, and chemically and determine the manufacturer of the carpet and this in turn could lead to the car manufacturer and even the make and model year–or at least a narrow range of years since car manufacturers change their products quite frequently. This would greatly help your police officer develop suspects.

 

 

Q and A: Can My ME Distinguish Death From Asphyxia From Death Due to Head Trauma?

Q: Here’s my book situation: A man puts a plastic bag over his head to kill himself. His wife wakes up next to him (after he nearly strangled her to death and she discovers he’s killed their son) and in her horror and rage cracks him over the head with a blunt object.

Here’s my question: Can the police/coroner/forensics determine which was the cause of death–suffocation or blunt force trauma? If so, what would the signs be pointing to asphyxiation?  Also, if it matters, this is set in 1969.

Judy Merrill Larsen, author of All the Numbers

http://www.judymerrilllarsen.com

A: If the victim died first from the asphyxia, the ME would have no problem since the blow to the head would cause no bruising or bleeding. At death the heart stops and blood flow ceases and a corpse will not bleed or bruise easily. So the ME would see a mark where the victim was struck but no bleeding or bruising and know that the blow was delivered post-mortem.

If he was still alive when struck, things become a little more difficult for the ME but he should still be able to tell. Bruising and bleeding at the site of the blunt trauma would show that the victim was alive when struck but if there is no significant brain injury found at autopsy he would know that the force of the blow did not cause death and the asphyxia must have. If there is a brain injury such as cerebral contusion (brain bruise) or bleeding into or around the brain, he might have difficulty determining the actual cause of death. Of course any evidence of blunt trauma would point to homicide and not suicide since someone using a plastic bag for suicide would not likely also strike themselves in the head.

But I see a bigger problem with your scenario. If she was unconscious from being strangled, she would wake up within 10 seconds to a minute or so after the pressure was released unless she had significant brain injury from lack of oxygen. If she were simply strangled into unconsciousness, which is due to blocking blood flow thru the carotid arteries to the brain and not blocking breathing, as soon as the pressure was released and blood flow reestablished, she would wake up very quickly. Much sooner than he could put a bag on his head and die from asphyxia. For her to be out that long would require some degree of brain injury and I don’t think that’s what you want. Of course, if he drugged her first and then strangled her to the point he thought she was dead, but she in fact wasn’t, then she would awaken when the drug effect wore off. Here he could be dead for hours before she awakened.

 

 

Q and A: Can My Serial Killer Make His Victims Float Face-up?

Q: My serial killer has predilections that make him want his (female) victims to float face up when they are found. He strangles them and then places them in the water, so they don’t actually die of drowning. Would plugging the throat or taping the mouth and nose shut (so air stays in the lungs) be a good way for him to achieve this effect? What else might work?

S.K. Davenport, Pittsburgh, PA

A: Plugging the throat or taping the mouth and nose would make little difference since there is not enough air in the lungs to cause a body to float. Virtually all bodies sink when first tossed into water. This is not absolutely universal as sometimes clothing can gather air and keep the victim afloat but for the most part they sink. They do not float again until the decay process has progressed to the point that gases have collected within the abdomen and the tissues and the body becomes buoyant. Most bodies float facedown for a very simple reason–the arms and the legs tend to fall in that direction rather than backwards so their weight keeps the body face down.

In order to make the body float he would have to do something to increase the rate of decay and since this is predominantly temperature dependent it would be best if the body was placed in warm water such as a heated pool, a Jacuzzi, or a swamp in Louisiana. Alternatively–and this is over-the-top sinister–he could inject air into the victims abdomen and chest and even the tissues of the legs and arms. If he injected enough the body would float immediately. In order to keep the body on its back, he would have to apply weights of some type that would weigh down the backside of the corpse. Maybe some large fishhooks placed deeply into the flesh and muscles with weights attached. Just a diabolical thought.

 
12 Comments

Posted by on January 4, 2013 in Asphyxia, Crime Scene, Q&A, Time of Death

 
 
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