Rigor Mortis: This term refers to the rigidity of the muscles of the dead person. It is no accident that a common term for a dead person is “stiff”. Your muscles hold their tone and are able to contract and release through a complex chemical reaction of two molecules in the muscle cells: actin and myosin. Two chemicals, acetyl triphosphate and acetyl diphosphate allow this to happen. When a person dies the body is in a particular position. Left in that position for a period of time, the body will reach full rigor or stiffness. This happens because the two chemicals ATP and ADP are not going through their normal cycle. So rigor starts right away, it strengthens throughout the body and reaches full rigor in about six to eight hours. The rigor will leave the body in about twenty-four hours. Evaluating this helps provide a range for the time of death. Sooting: It is important to determine how far the muzzle of the gun was to the victim’s body at the time the weapon was discharged. The term sooting describes deposits of gunpowder residue on the skin of the victim. This burnt gunpowder can be washed or wiped off the body. Because it has little mass and would best be described as smoke residue, it can’t travel far from the barrel of the gun, so sooting is an indication of a close gunshot wound. Gunshot wounds are always described within a range. I define close range from near contact with the skin as approximately six to eight inches away from the target. Stippling: This is another term that relates to distance of the gun from the victim at the time of discharge. Stippling is partially burnt gunpowder residue. It has greater mass than the smoky, massless sooting residue and therefore can travel farther than soot. Once this unspent powder hits the victim’s skin it causes little red dots as it burns the epidermis, called “tattooing.” Booth sooting and tattooing can occur in a close rage shooting. If only stippling exists, then the gun was farther away. In my experience stippling occurs when the gun is eight inches to a little better than twelve inches away from target. All of these ranges depend upon the weapon and the ammunition used. Ranges can be reproduced with similar guns and ammunition to those in the incident by calibrating the distance from a whiteboard and then firing at multiple ranges. Victimology: A victimology is one of the keystones to deriving meaning from the evidence of an investigation. After the evidence is collected, documented and processed, the effort to give meaning to what all the evidence tells us is called “evidence reconstruction.” Evidence reconstruction begins with first studying the victim. This process is called building a victimology. The entire life is of importance, especially the last 48 hours before to death. In the first episode it readily became obvious that the victim knew the killer. There was passion involved in the assault. The victim was in the midst of trying to change her life as evidence of textbooks around the scene. A victimology must give meaning to why the victim was a victim. DNA Profile: Your DNA defines who you are uniquely. Most of your DNA is just like everybody else's but there are areas in the double helix that identify you more accurately than fingerprints. There is DNA in the nucleus of the cell, representing the profile of both the mother and father of the sample, and there is DNA from the engines of the cells, the mitochondria, representing only the maternal side of the sample. Each cell has many mitochondria, but only one nucleus. In most cases, mitochondrial DNA testing is done because a smaller sample is sufficient enough for identification.
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Thanatology: The investigation of the mechanisms and forensic aspects of death--including the biological cause of death, the manner of death (homicide, suicide, accidental or natural), and the grieving process (social and psychological) for the families and loved ones left behind. Coroner: The word “coroner” is derived from the old English word “crowner.” Crowners worked for the king and their primary function was to travel to the king’s territories and investigate things such as fraud, other theft and yes, death. The king needed resolution of the deceased’s property since land distribution was determined by the cause and manner of death. The coroner held a position similar to the sheriff, only with greater emphasis on things “on or about the body.” By the twentieth century the coroner was generally someone with some medical background. In large populated areas such as New York, medical examiner systems developed. Today most states have medical examiner systems or hybrid systems such as my office in Dauphin County, Pennsylvania. The systems depend on varying population areas, budget restraints and geographic conditions. The quality of the system is determined by the practitioners; I have met amazing individuals in both. I have a background in forensics and medical legal investigation and work very closely with a board certified forensic pathologist. All my deputies are nationally certified in medical legal death investigation and are constantly taking courses to keep their skill up to par with new advances in investigation, and investigative tools. Whether in a medical examiner system or in a hybrid, the task is the same: recognize the evidence on or about the body, document that evidence, and process it through a chain of evidence. In the end we answer to no king. We cooperate with the police and law enforcement but our objective in not to charge or to arrest. Our mission is the solemn task of “speaking for the dead.” Ultimately, we are their advocates when they can no longer tell their story. Dead: You would think that death is easy to define but it is not. Many states have different protocols for establishing the declaration of death. In general, death is when the body ceases to function in maintaining life. Death is death when it is irreversible. In most cases a person on life support must go through two separate electroencephalographs (EEG) over a period of time; say 24 to 48 hours. If the individual fails to have brainwaves sufficient to support respiration and heart rate the individual is termed “clinically dead”. Primary Scene: This is the scene where a crime or the cause of the death occurred. Whatever action caused the death happened at this scene. Secondary Scene: This is an area where the body was transported to after the initial attack. This could be a dumping off point or an area secluded so the body could be hidden. Just because it is not the primary scene it doesn’t mean important facts can’t be found, tire tracks can lead to the perpetrator's car and at least tells you that the perpetrator drives. It may also indicate how familiar the perpetrator is with the area. Chain of Evidence: For the protection of the innocent and the prosecution of the guilty, there has to be an assurance that evidence is properly documented at the scene, collected in a manner that is scientific, processed and stored for examination. Each piece of evidence has to have a continuous documentation of who collected the evidence, where it was collected, the time and date it was collected, along with documentation of every person that touches the evidence and the purpose for handling the evidence. It is a chain of who handled the evidence and why. Livor Mortis: A coroner or medical death investigator is often asked when the person died. Livor mortis can give the investigator a range of time as to when the person died. Unless you are looking at your watch and happen to see someone die, you will never be able to give an exact time, only an estimated range. One of the patterns on a dead body that can help establish the range of the time is a purplish discoloration. This is caused at the time of death when the heart stops circulating the blood and the blood goes to the dependent parts of the body. So imagine seeing a dead body lying, face down, on stair treads. The blood would flow towards the head. If the body is face down livor mortis would be present, much more so in the chest and face area. In most cases the color of discoloration is purple. It can be cherry red at times because of cold temperatures, carbon monoxide or arsenic poisoning. Livor mortis tell us the position of the body due to the coloration of redness and blanching of white areas where the tissues are under pressure. If you push on your own hand right now, you will see, just for a second, the skin blanches and has a white or lighter spot where you applied pressure. The other these color patterns are movable at first but as the blood pools in these areas of the body the pressure starts to push the blood out of the small vessels and it begins to stain the area outside the cells. So within about six to eight hours the lividity or livor mortis will become “fixed”. This can tell the investigator that the death was not recent but most likely hours before he arrived on the scene. This information can be given to police and then compared to witness statements. Algor Mortis: This is the temperature of the body when it is examined. It is compared to the normal human temperature of 98.6 Fahrenheit. When a person dies they stop producing energy in the cells and thus lose the ability to produce heat. There are many factors to determine the rate at which the deceased will lose heat from their body: - What is the ambient temperature or room temperature where the body is found? - What is the deceased body type: heavyset, thin or a more standard weight? - What are they wearing? - Where are they lying: on stone or cement, in water or on carpet? - Is there constant air flow over the body? All these factors and many more can influence how quickly heat can leave a dead body. As a very general rule, given room temperature, normal clothing, normal body temperature at death, in the first hour the deceased will lose approximately 2 degrees Fahrenheit and then approximately 1 to 1.5 degrees each hour after. Again this is a rough approximation and never an exact science. Many times checking the cell phone records, the mail at the door or the statements of witnesses can give you a much or better time of death. It is still good to be able to calculate these ranges and see if they concur with other data. |
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