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Death Investigation. Death Investigation: Learning Objectives. Describe the role of the forensic pathologist Describe the external, internal, and toxicology phases of an autopsy Distinguish cause and manner of death Describe the common causes of death
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Death Investigation: Learning Objectives • Describe the role of the forensic pathologist • Describe the external, internal, and toxicology phases of an autopsy • Distinguish cause and manner of death • Describe the common causes of death • List various categories associated with the manner of death • Describe chemical and physical changes helpful for estimating time of death • Describe the role of the forensic entomologist in death investigation
Death Investigation: Vocabulary • Algor mortis • Autopsy • Cause of death • Forensic anthropology • Forensic entomology • Forensic pathology • Livor mortis • Manner of death • Petechiae • Postmortem interval (PMI) • Rigor mortis
Death Investigation: Harold Shipman, Dr. Death • 1998—81-year-old widow Kathleen Grundy, who was believed to be in good health, is visited by her physician Dr. Harold Shipman • Hours later Mrs. Grundy is found dead on her couch by friends that came by to visit
Death Investigation: Harold Shipman, Dr. Death • Dr. Shipman pronounces Grundy dead and informs her daughter, Angela Woodruff, there is not need for an autopsy • Woodruff is surprised to find a will that leaves all of Grundy’s money to Dr. Shipman • The will is identified as a forgery, and Grundy’s body is exumed
Death Investigation: Harold Shipman, Dr. Death • The autopsy on Grundy showed lethal levels of morphine • As police investigated, all Shipman’s victims appeared to all be elderly women who were found sitting in a chair or lying clothed on a bed • Clinical audit estimated Dr. Shipman killed at least 236 of his patients over 24 years • Most were attributed to fatal doses of heroin or morphine • Convicted of murder, Dr. Shipman hanged himself in his jail cell in 2004
The Role of a Forensic Pathologist • Forensic pathologists are investigative personnel, typically medical examiners or coroners, who investigate the cause, manner, and time of death of a victim in a crime
Scene Investigation • Death investigation involves: • Documenting and photographing the undisturbed scene • Collecting relevant physical evidence • Attempting to determine the time of death • Ascertaining any postmortem locations and whether any postmortem movement of the body occurred
Scene Investigation • Critical phase of death investigation will be a preliminary reconstruction of events • Blood spatter/blood flow patterns must be documented • Blood should be sampled when found at the scene • When a weapon is involved, a concerted effort must be made to find the suspect weapon
Scene Investigation • Paper bags should then be placed over the hands & feet to preserve evidence • Photographs must be taken before the scene is altered in any way—may play a role in reconstructing events • Often the initial phase of investigation will focus on determining the identity of the deceased • May be complicated based on the degree of decomposition
The Autopsy • An autopsy is a surgical procedure performed by a pathologist on a dead body to ascertain the cause of death • Clinical autopsy: confirm diagnosis, presence and extent of disease • Forensic autopsy: determine cause of death • All steps of forensic autopsy must be carefully documented and photographed • Documentation should include date, time, place, examiner, and anyone in attendance
Evidence from the Autopsy • Tissues and organs are kept for pathological and toxicological reasons • Evidence should be collected ASAP! • The following should be collected and sent to the crime lab: • Victim’s clothing • Fingernail scrapings or clippings • Combing from the head and pubic areas • Buccal swab • Vaginal, anal, and oral swabs (in sex-related crimes) • Bullets recovered from the body • Swabs of areas, such as breasts or penis, suspected of being in contact with DNA • Hand swabs from shooting victims
External Examination • Broad overview of the condition of the body and clothing • Damage to the clothing should be matched up to injuries on the body • General characteristics should be noted: • Sex • Height • Weight • Approximate age • Hair color • Physical condition
External Examination • Presence of tattoos, scars, punctures and track marks should also be noted • Mouth/nose examined for vomit, blood, and/or trace evidence • Ears are checked for blood • Nose is checked for irritations (drugs) • Fingernails are checked for skin & DNA
External Examination • Classifying injuries: • Distinguishing between different types of injuries • Abrasions, contusions, lacerations, sharp wound injuries, genitalia (sex-related crimes) • Stippling (marks left by discharge of a firearm) • X-rays are sometimes performed (GSW & stab wounds
Internal Examination • Removal of all internal organs • Weighing, dissecting, and sectioning of each organ • Y-shaped incision from the top of each shoulder to the pubic bone • Examination of the cranium: • Incision from behind one ear to the other • Peel back scalp • Saw the skull in a circular cut—removal of the brain
Internal Examination • Special care is taken to identify any preexisting conditions • Toxicology Report: • Blood, stomach contents, bile, & urine samples are taken • Blood is tested for drugs & alcohol • Tests are also done for poisons • Some drugs redistribute or reenter the blood after death & thus may complicate the interpretation of postmortem blood levels of these structures
Cause of Death • The main objective of the autopsy is to determine the cause of death • This means to identify the injuries or disease that led to the chain of events resulting in death
Blunt Force Injury • Caused by a non-sharpened object such as a bat or pipe • Can abrade (scrape) tissue or laceration • Can crush deeper tissue will cause contusions (bruises) • There is often trouble in determining the age of contusions • Can exhibit the pattern of the weapon used • Outward appearance doesn’t always coincide with the injuries sustained on the inside of the body
Sharp Force Injury • Occur from weapons with sharp edges (knives or blades) • Cutinjury that is longer than deep • Stabinjury that is deeper than it is long • Scenes that involve sharp force trauma are usually bloody and unruly • Examination of victim for defensive wounds is important
Asphyxia • Variety of conditions that involve interference with the intake of oxygen • Fire victims—high levels of CO2 • Soot can be observed in victims that were alive during the fire • Cause of death in hanging—stopping of blood flow to the brain • Victims may show signs of petechiae on the eyelids, swollen face • Pinpoint hemorrhaging often observed in the whites of the eyes • Caused by capillaries bursting
Asphyxia • Petechiae more common in strangulation than hanging • Hyoid/Thyroid cartilage intact in hanging broken in manual strangulation • In hangings important to document exact positioning of the body • Type of knot could be extremely useful • Defensive wounds common • Smothering materials that block mouth, nose, & internal airway
Gunshot Wounds (GSWs) • Estimated range of fire is one of the most important characteristics • Investigator will compare powder residue distribution around the wound • Gunshot residue on the victim’s hands could indicate suicide, but not always
Gunshot Wounds • The autopsy must include a determination of the “wound track” • Following the path of the projectile from entry to exit • A gunshot wound may not explain death • Victim could bleed to death in minutes or hours • Infection can also contribute • Especially for abdominal gunshot wounds • Pneumonia can set in for victims shot in the head that haven’t died
Substance Abuse • Forensic pathologists will test for drugs in almost all investigations • Drugs can directly cause death, or can cause complications that can contribute to death
Manner of Death • Manner of Deathis the determination made by a forensic pathologist of the cause of death • 5 Categories: • Homicide • Suicide • Accidental • Natural • Undetermined
Manner of Death • Homicide • Non-accidental death resulting from grossly negligent, reckless, or intentional actions from another person • Suicide • Result of an individual taking his or her own life with lethal intention • For determination of suicide, it must be determined that the person acted alone • If there is any doubt, the death is declared accidental/undetermined
Manner of Death • Accidental • There must not be intent to cause harm through gross negligence on the part of the perpetrator/victim • Natural Causes • Sometimes difficult to distinguish between accidental and natural causes • Can include disease and continual environmental abuse • Undetermined • Declared only when a rational classification cannot be established
Estimating Time of Death • Pathologist can never give exact time of death • Algor Mortisis the process that occurs after death in which the body temperature continually cools until it reaches the room temperature • Must be performed at the scene as early as possible • At average room temperature of 70-720, the body loses heat at about 1-1.50 an hour • Influenced by the size of the victim, clothing, and room temperature
Estimating Time of Death • Livor Mortisis a medical condition that occurs after death and results in the settling of blood in areas of the body closest to the ground • Skin becomes bluish/purple in these areas • Begins as soon as 20 minutes after death • Continues for up to 16 hours after death • Lividity, coloring is fixed • Lividity indicates approximate time of death • Environment and body temperatures affect livor mortis • Different lividity patterns may indicate the body was moved
Estimating Time of Death • Rigor Mortis is a medical condition that occurs after death and results in the stiffening of muscle mass • Begins within 24 hours of death and disappears within 36 hours • Develops in the position the body was in at time of death (freezes the body) • Roughly indicates time of death
Estimating Time of Death • Potassium Eye Levels: • Determining potassium levels in the ocular fluid (vitreous humor) can help determine time of death • Release of potassium is dependent on room temperatures • Stomach Contents: • Quantity, consistency, color of bile, and degree of digestion can help determine time of death • Can contain partially digested or dissolved pills • Decomposition: • Degree of decomposition of the body can also help determine time of death
The Role of the Forensic Anthropologist • Forensic anthropology is the use of anthropological knowledge of humans and skeletal structures to examine and identify human skeletal remains • Gender of deceased can be determined by the size and shape of various skeletal features, especially those of the pelvis, skull, or cranium • The height of a victim when alive can be estimated by measuring the long bones of the skeleton, especially those in the lower limb
Forensic Anthropologist https://www.youtube.com/watch?v=xIbbok9SbKY https://www.youtube.com/watch?v=nW1I2eYfdwc
The Role of the Forensic Entomologist • Forensic entomologists can approximate how long a body has been left exposed by examining the stage of development of fly larvae on the body • Information about the arrival of another species of insects may also help determine the postmortem interval. The sequence of arrival of these groups depends mostly on the body’s natural decomposition process • In general, insects first colonize the body’s naturally soft orifices. However, if open wounds are present, they will colonize