In 2006, a construction sites for relocating some water pipe lines in Hong Kong led to a discovery of 8 skeletons (1 adult and 7 children, according to all local news reports). The locals, especially those from one generation older immediately thought this was linked to this spooky old belief.
So last time, I expressed my concern on how the Hong Kong Police and Firemen had mistreated the crucial trace evidence, namely the concrete casket. And I also opposed their methodology. Some of the readers thought that police should be more experienced on handling these cases than me, and also thought that the law enforcement units had made this judgment after chains of thorough thinking.
I supposed I am not in a good position to comment further on how their approach was when they were at the scene. After all, I was not at the crime scene in person. Also, readers state that that was indeed the raw differences between theories, archaeology and the reality. I am only wishing to use the following space to replied to three of the main questions raised by the readers. I have also cited the Los Angeles Medical Examiners case report, in hope of the M.E. would be able to shed some lights on the questions the readers made from their study and research.
Question 1: The size of the concrete casket is too huge! May be they are not scanned because the law enforcement was not able to transfer them for scanning?
If you ever watched any crime shows on TV (of course, Bones is a good example. Everyone will yell “back to the lab!”), you will see they are always able to transfer whichever evidence they found back to the lab before further analyzing. Reality, not so much. This is how Ground Penetrating Radar comes into play. In archaeology, Ground Penetrating Radar (GPR) is used to detect and reflect any buried artifacts, monuments, archaeological sites. It is especially handy when archaeologists are about to look for hidden burial sites and buried remains. GPR allows noninvasive examination, and very helpful for experts and scientists to learn about the structure of the hidden architectures and bodies. Furthermore, size of a GPR is only about the size of a vacuum. Some companies even invented the GSSI Mini, which is about the size of a laptop for carrying scientists to have easy access in the field. All GPR and GSSI Mini come with a monitor, and very easy to connect to the laptop. That said, it is easy to document digitally the detected images. One may use slightly more time on using the GPR before stepping or unfold the crime scene, yet save the team and resources from doing extra and additional steps and procedures in the later investigation. In this case, that would be the suspicious broken palm, posture of the body, etc.
Question 2: It was mandatory to crack the concrete casket open, as the body was decomposing already.
News and police report claimed that the concrete casket was dried by the time of discovery. Yet, concrete would not dry but only cure and hardened. The hardening and curing of concrete, in other words, does not come from the evaporation of water from the chemical composition of the concrete. Rather the water molecules have transformed, merged and bonded together with the concrete particles as part of their chemical structure. An experiment pointed out that the mass of concrete before hardening/ curing is about the same with after . The only slight difference between the mass was from the evaporation of the water on the concrete surface that with no cover. Last time, I have also mentioned that concrete is relatively porous. When cement hardens, it means that the water molecules and air molecules have filled in all those pores. This type filling makes concrete looks strong but indeed not. That said, it is relatively soft inside, while the outside of the concrete looks hard.
And for the body that was covered by the concrete, the decomposition of it liquefies from inside to outside, and all the decomposition was triggered by the enzymes in muscles. During the hardening process of the concrete, since it is a exothermic reaction (i.e. it releases heat in the whole process), the interior of the concrete casket would reach 175F in the first few days, which results an acceleration in the decomposition rate. After curing, the concrete becomes a good insulator that blocked the air and heat to reach the body, and thus successfully decrease the rate of decomposition again.
During the stage of decomposition, body liquids (any liquid in the body, you name it :)) would leak out of the body. Normally, as in general when a body is exposed to air, atmospheric air would help evaporate liquids and water. However, when a body like the one in this case is being buried in a concrete casket, all the fluid is trapped in the casket, and at the end turned the soft tissues into a mush. At the end, fluids would leak outside the casket, or concrete casket. This is not only something visual but also would give a strong odor. Evenly so, it does not mean an invasive act should be taken to the casket. Keep in mind that bodies starts breaking down the moment the heart stopped beating.
Question 3: Readers think that using merely textbook archaeology, i.e. using brush in the act, has not thoroughly considered the scenario at scene.
To be honest, this is some attitude that forensic scientists should have and maintain all along. In the forensic field, a lot of the tools we use are indeed very creative. For instance, you would find ladles on the autopsy table to scoop out fluid (for example inflammatory fluids in lungs) during autopsy; also would find those big stock pots in decomp bodies autopsy room for forensic anthropologists to do maceration. All these kitchenware is used with one and foremost premise: will not affect the quality of the collected evidences, or would not contemning evidences.
Los Angeles Medical Examiner Office claimed that there were only 5 cases of concrete casket located, till 2008, in the past 18 years in a report. They also stated in the report that, though cement and concrete affected the calculation or estimation of accurate postmortem interval, at the sam time they welly preserved all trace evidences . In these 5 recorded cases, medical examiners were taken things slow, and excavate the bodies layer by layer in order to estimate the cause of death and time of death. Among all, LA medical examiners also indicated the frequent application of metal detectors and radiography in order to pinpoint the posture of bodes, and location. Sledgehammer and chisel are only implemented in a very much later stage, or only when they are sure it would not damage the body.
Back to the discussion, should we use heavy tools like sledgehammer and chisel, or only brush? Both. The foremost premise here is to not damaging the evidence. Only use heavy tools when the remains inside are well-documented. Also, the methodology with chisel should be go horizontally instead of vertically in order to reveal the context of the casket and the body.
Sad but true, concrete casket or related research is not commonly seen and discussed in the academia. These caskets can only open when all the conditions and situations are well-documented. In delicate crime scene like this one, officials should prioritize the preservation of crime scene in front of investigation just yet.
 Lesson 5: So, You Think Concrete Dries Out? (n.d.). Retrieved April 11, 2016, from
Toms, C., Rogers, C. B., & Sathyavagiswaran, L. (2008).
Investigation of Homicides Interred in Concrete—The Los Angeles
Experience. J Forensic Sci Journal of Forensic Sciences, 53(1), 203-207.
On March 30, 2016, Hong Kong local media, Apple Daily reported about a homicide that with a concrete-made casket. The concrete was found in one apartment in one of the neighborhood in Hong Kong, Tsuen Wan. The concrete casket was 1m x 1m x 0.5m and covered with a wooden box, and was placed in the center of the living room. Other than the concrete-wood casket, there were a lot of air-fresheners placed in the living room too. Police and firemen arrived the scene, and found the strong odor is originated from the wooden box in the living room. They decided to crack the casket, and handled the body to the M.E. right out of the casket. From the angle of forensic anthropology, and forensic archaeology, I would like to point out that the methodology police and firemen used to handle the casket is not appropriate.
Recap: Forensic anthropology is the combination of osteology and physical anthropology that applied in the legal context. Usually, forensic anthroplogists would only deal with human remains in advanced decomposition, skeletonization, human bone fragments, burnt remains, or other remains that have difficult time to give a positive identification from soft tissues.
Back to the case, first and foremost, the concrete casket. Concrete is the cured cement. Cement is a relatively alkaline material and very porous in itself. Concrete casket is very effective in insulating the body from contacting the air, which in turn, slows down the reproductive rate of bacteria within the body, as well as decreases the probability for flies laying eggs on the body. For, soft tissues decomposition mostly because the bacteria within digested our body and the occurrences of maggots. These two teeny tiny organisms enjoy the decomposition feast the most! Also, because the concrete could insulate the contact between the air and the body, the decomposition rate in general is slower in the concrete casket than exposing it in the air. That said, if the correct evidence collection methodologies used, a lot of physical, biological and trace evidences would be too preserved in the concrete casket. Therefore, without examine the concrete casket and use chisel or sledgehammer to break the concrete would be one serious wrong move, and here are the three main reasons:
1. Cracking the concrete casket is an invasive act. Once the concrete is cracked and broken, no one could recover it back to the original context. A fluoroscopic examination should be done and evaluated before any invasive act. With today’s technology, it would be easy and efficient to scan the whole concrete block before cracking it open. That way would allow the M.E. and corresponding law enforcement agents have a better understanding with the posture, number of bodies, and position of remains. Also, some of the remains might liquidfy or oxidize once contacted with air because of some chemicals they exposed to before concealed in the concrete. Straightly cracking it open, simply ignored this possibility.
2. Another risk of cracking open the concrete casket directly would be: what if there are more than one body? Although according to the intel and the missing person report, there was only one missing individual, and also because of this, police mainly focuses on looking for this particular person. Yet, if there are really more than one set of remains, directly using a chisel or sledgehammer without scanning the concrete in advance, would possibly damage the remains inside. The concrete casket, like the apartment, is a crime scene. One of the main missions for forensic anthropologist to determine first and foremost, would be the minimum number of individuals, or MNI. Anything in and out of the concrete casket is part of the evidences. Local news report stated that the right hand is cracked and broken because of the cement. Little did we know, if it was broken because of the cracking of casket, and thus resulted this postmortem trauma.
3. Direct usage of sledgehammer and chisel is not recommended. In forensic archaeology, the most useful tools would be those of carpenters–brushes, or even tooth brush. Only after fully documented the conditions of the casket would consider to crack the concrete. And would not use any chisel when getting close to the remains. That way, we could make sure the context of the body is well-preserved and complete-documented. Though this way is slow (could not deny this), yet can protect the remains and preserve the maximum amount of evidences, from pollen to hair to adipocere (aka grave wax).
Though body disposal in concrete is not a common case, it is definitely not the first. When handling body disposal like the abovementioned case, it is very important to keep in mind that speed of cracking the case is the least concern, as you have this fragile and one-time crime scene needed to handle and evaluate in optimum condition.
A thief has been convicted in London after
breaking into a trap car and being covered in a liquid that’s invisible
to the human eye. UV lights showed Lokombe’s hands glowing green with the indelible spray, proving his guilt.The
luminous pigment in SmartWater is used to protect cash deliveries,
covering notes with invisible and traceable dye in the event of a
Q: how useful it is if we found a hair from a crime scene? Will it tie us to a unsup?
A: yes, even put the unsup to jail! In general, each person loses 100 human hair everyday. It is easy to leave trace at the crime scene, or through physical contact. And each strand of hair is like a database that stores with data that allows scientists or experts to trace back up to 6 months ago. With each hair has a constant growing rate (in general) of 1 inch each month, it would help unlock data like medical condition, as well as the use of drugs too! A lot can pull out from the head of a hair, such as but not limited to: dietary habits, nutrition info, drugs consumption, diseases. With these specific info, linking a person to a crime scene is not as hard.
Q: what is the definition of forensic countermeasures? This phrase sounds fancy!
A: this phrase in fact is pretty self-explanatory. First, you have to understand what “countermeasure” means. “Countermeasure” means an action, an incident, or a process that prevent the normal forensic protocols. It threatens the integrity of the forensic works.
Take an outdoor crime scene as an example. The forensic countermeasure could be the unpredictable rain (though it is a natural one), which would watch away unprotected evidence. It also could be scavenging animals, trespassed people, and so forth. As long as the acts that threatens the validity of forensic evidences that are not yet protected by the chain of evidences, regardless if it is natural or artificial, it is already a sort of forensic countermeasures.
Simple concept but with fancy saying, isn’t it?
Q: Is it possible to tell if victims died from drowning and the time of death of remains found in water?
A: yes, for sure there are several ways to tell if the victims were drowned. One of the ways, that is also help determine the time of death of remains found in water is to evaluate the diatom level.
Diatom refers to a diverse group of algae. It has no specific structure or characteristics as it is consider a general term of groups of algae that inhabit the remains. Yet, the migration of diatoms, meaning the sequences of diatoms in the body should tell the time of the body in the water by calculating the schedule.
The same applies to the drowning victim too! Yet, during the drowning process, victim should also have inhaled some of the fresh water (only in fresh water will find diatoms!). So in the lungs, ME should be able to find fresh water and diatoms for calculation, as well as backward calculating the appearance of diatoms in order to work out the time of death.
P.s. Diatoms belongs to the Forensic limnology department, which is a sub-discipline of forensic botany, fyi : ) !
Q: are the dead wives tales true at all? Meaning, our nails and hair do grow after we died ?
A: Yes and No. Yes, because it does look like it grows, like illusion. No, because it is NOT REALLY GROWING.. Both hair and nails look like they grow after the heart stopped working because of the skin surrounding them are dehydrated. They shrink, and thus make it appear to be longer. Funeral homes sometimes will moisturize the bodies when they are doing the prep to counteract this.
Other than the hair and nails, the chin also dries out, and pulling towards the back of a skull, thus looks like more prominent. So does the goosebump effect, because of the contraction around the hair muscle (remember we talked about in the last few q&a, after we died, our muscles are not able to relax, not unable to contract!).
These all biological responses give the sense of horror!
Q: What is chain of evidence? Is this important?
A: Two solid Yes to the questions! Chain of evidence basically refers to the sequencing of evidences found following to this order:- identification,collection,analysis,storage, preservation, transportation, presentation in court and return to owner/ next of kin. In short, it includes where, when and what the evidence was retrieved from. Also, the chain of people that have handled the evidence are also included in the long description list. This being said, the concept is SUPER important because without the proper chain of evidence executed, the evidence could be contaminated, and resulted from test failure, and more importantly, could be invalidated by the judge and jury. On top of that, this is very important as some crimes could have gone cold yet have not passed the Statute of allegation/Prosecution. The contaminated evidence would not help if in any of the cold case.
Q: Seriously, in general, what will happen to our body once our heart stopped?
A: The story goes: when the heart stopped beating, no pressure to chase the blood around, gravity causes the red blood cells sink through and settle in the dependent parts. This results a red/ purplish discoloration, which we called LIVOR MORTIS Then we have RIGOR MORTIS, which is the stiffening in the muscles. It is because the brain stopped working, and stopped RELAXING (Not Contracting) the muscles. As well as, cooling of the tissues or ALGOR MORTIS. The latter two usually kicked in as soon as 20mins after death to 3 hours; capillaries will be congealed in 4-5 hours and maximum livor mortis occurs within 6-12 hours (though size of the patches increase within first 3-6 hours)