Forensic Science: Death Investigation Questions Answered 100% correct

Forensic Science: Death Investigation Questions Answered 100% correct Medical Examiner -Required to be an M.D. -Specialization in pathology -Usually board-certified -Will make determinations using all available information Medicolegal Death Investigator -Personnel from ME or Coroner's office who respond to a crime scene and coordinate efforts with police and crime scene personnel. -Collecting information to assist in determination of Cause and Manner of Death -Additional personnel used to help determine Cause and Manner of Death, or identification -Forensic Anthropologist -Forensic Odontologist -Forensic Entomologist Forensic Pathology -Examination of a body -Cause and Manner of Death Cause of Death -What is the action that initiates the series of events ending in death? -What is the character of the injury that started the chain of events? -May include "contributing factors" if death is prolonged, adverse medical conditions -Usually the medical reason someone dies, Different types of Cause of Death -Blunt Force Trauma -Sharp Force Trauma -Asphyxiation -Gunshot Wound to Head -Heroin Toxicity -Undetermined -Atherosclerosis Blunt Force Trauma Injuries caused by non-sharpened object Sharp Force Trauma -Occur with weapons that have sharpened edges -Tissue is sliced, not torn or crushed -Generally bloody scenes -Location of wounds are important -"Defense wounds" "Defense wounds" -Forearms -Fingers -Palms -Back of hands -Lower extremities -Lack of defense wounds is also important Gunshot Wound Originates from a projectile fired from a firearm Post-Mortem Examination -Determination of Cause of Death done by performing an autopsy. -Information gathered in the autopsy will also be used to determine the Manner of Death -Records and photographs from post-mortem exam will be used during court proceedings. -Careful examination of body, wounds, patterns, toxicology. Autopsy Examination of a body post-mortem Evidence collected during autopsy -Clothing -Sexual Assault Kit -Fingernail scrapings/cuttings -GSR swabs -Swabs -Blood -Vitreal fluid -Head/Pubic hair combings -Projectiles 3 Basic steps of Post-Mortem Examination -External Examination -Internal Examination -Toxicology External Examination General condition of body Internal Examination -Y -shaped incision -Removal and weighing of internal organs -Cranium examination More on pg. 27 Toxicological Samples -Blood -Stomach contents -Bile -Brain matter -Liver -Vitreous humor Manner of Death 1. Homicide 2. Suicide 3. Accidental 4. Natural 5. Undetermined Homicide Death through reckless, intentional, or grossly negligent actions of another Suicide Result of an individual taking his/her own life with lethal intention. Must be able to show that act was done alone and without outside help. Must be intentional. Accidental Must be no intent to cause harm or death through gross negligence Natural -Disease -Chronic drug/alcohol abuse -Longtime exposure to toxins Undetermined -No rational classification can be determined. -Physical exam finds no mechanism of death, absence of meaningful findings in toxicological exam SIDS -Sudden Infant Death Syndrome -Anyone under the age of 18 Time of Death -Estimation/Approximation -Never exact -Based on the interpretation of various post-mortem features and characteristics due to physical and chemical changes -Environmental considerations -Insect and animal activity -Gives investigators a general idea of how long the deceased has been dead. -gives investigators an idea if the deceased was moved after death. Algor Mortis results in the loss of heat by a body as general rule the body loses heat by 1 to 1-½ degrees Fahrenheit per hour until the body body continually adjusts to equalize with the environmental temperature. Rigor Mortis -Stiffening or contraction of muscle mass. -Estimation of TOD is not always used and highly ts in the shortening of muscle tissue and the stiffening of body parts in the position at death. Occurs within the first 24 hours and disappears within 36 hours. Stomach's contents may reveal the deceased's last meal The extent of digestion can help with determining the time of death. Cadaveric Spasm -Stiffening of hands/arms immediately -Not the same as rigor mortis -May find weapon clutched in hand of deceased. Livor Mortis -Pooling and settling of blood within the blood vessels Livor Mortis (Lividity) -Begins about 20 minutes - 3hours after death -Blood- no longer circulating-changes from bright red to purple due to loss of oxygen -Parts of the body remaining in contact with objects will remain white. -"Blanching" Decomposition -Once decomposition occurs, all preceding methods of TOD estimation can no longer be used. -Two main functions of decomposition 1. Autolysis 2. Putrefaction Autolysis Self-digestion by body cells enzymes Bodies in Water -Swelling in hands- 3-4- -Skin separation- 5-6 days (body), 8-10 days (hands, fingernails) -Floating- 8-10 days warm water 2-3 weeks cold water. Forensic Anthropology Is primarily concerned with the recovery, examination, and identification of human skeletal remains. Forensic Entomology The study of insects and their relation to a criminal investigation. Forensic pathologists Can determine the amount of potassium in the vitreous humor and use it to approximate the time of death. Will routinely order toxicological tests for the presence of drugs in nearly all autopsies. Can never give an exact time of death, but can give a range (hours, days, weeks, years)