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Death Investigations

Death Investigations. Chapter 7. Introduction. A basic requirement in a homicide investigation is to establish whether a death was caused by criminal action. Classifications. Four Types of Death Natural – non criminal Accidental – non criminal Suicide – non criminal

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Death Investigations

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  1. Death Investigations Chapter 7

  2. Introduction • A basic requirement in a homicide investigation is to establish whether a death was caused by criminal action.

  3. Classifications • Four Types of Death • Natural – non criminal • Accidental – non criminal • Suicide – non criminal • Homicide – Non criminal or criminal

  4. Heart attacks Strokes Fatal diseases Pneumonia SCDS Old age Cancer Natural Causes • Typically a person who dies of natural causes has been under a doctors care. • However, sometimes a death is made to look like it is from natural causes.

  5. Drowning Falling Poisons Car wrecks Work accidents People can also be pushed off a roof and make it look like a fall. Accidental Deaths

  6. Suicide • The intentional taking of one’s own life. • In most states it is not a crime to commit suicide but it is to assist in it. • See Dr. Kevorkian • What do you think? • The case of Karen Dodd

  7. Homicide • If another individual is the direct or indirect cause of the death, it is classified as a homicide. • Can be either criminal or non criminal • Classifications: • Criminal • Murder (first, second and third degree) • Manslaughter (voluntary and involuntary) • Non criminal • Excusable and Justifiable

  8. Murder • The most severe statutory crime • One can receive life and up to death as punishment. • 1st degree • Requires premeditation • Some states require that an intentional death is in conjunction with a another felony crime.

  9. Murder • 2nd Degree • Intent to cause death, but no premeditation. • An example here would be a violent argument that leads to a spontaneous killing. • 3rd Degree • no premeditation or intent • More reckless such as shooting into a room where people may be.

  10. Manslaughter • The unlawful killing of another person with no prior malice. • Can be either voluntary or involuntary • Voluntary • Heat of the passion • Involuntary • Extreme negligence

  11. Non Criminal Homicide • Excusable • Someone runs in front of your car and you hit them not on purpose and they die. • You were using ordinary caution • Justifiable • Self defense • Who in the class would use deadly force if someone broke into your home? Is this self defense?

  12. Elements of the Crime • Causing the death of a human • 1) Prove that the suspect caused the death • 2) Prove that the victim died as a result of the action that the suspect caused. • Premeditation is the element of 1st degree murder that sets it apart from all other classifications.

  13. Intent to cause death • Intent is a required element of most categories of criminal homicide. • Evidence must show that he crime was committed intentional and not accidental. • Intent and premeditation are not the same thing. • Most passion crimes involve intent but not premeditation for example.

  14. Heat of Passion • Results from extremely emotional and or volatile arguments between 2 people. • Adulterous affairs • Family member raped • Seeing a brutal assault on a friend or family member.

  15. Special Problems in Investigations • Special problems in homicide investigations include pressure by the media and the public, the difficulty of establishing that a crime has been committed, identifying the victim and establishing the cause and time of death. • Equivocal death – may be two or meanings, and the case may be presented as either a homicide or a suicide depending upon the circumstances. • The Leija shooting case example.

  16. Suicide • More occur in teens and the elderly • The reasons for a suicide need to be determined • Is there a note? Does handwriting match? • Check on prior arrangements as such w/ funeral home. • It could be a natural cause of death also – be sure • Families never want to admit their loved one committed suicide.

  17. Suicide by Gunshot • Gun held against head • Wound in mouth or in right temple if right handed, left if left. • Not shot through clothing except if shot in chest. • Weapon present • Held tightly in hand

  18. Suicide by Cutting • Hesitation wounds • Wounds under clothing • Weapon present, especially if tightly in hand. • Usually throat, wrists and ankles. • Seldom disfigurement. • Body not moved.

  19. Suicide by Police • This person is too frightened to kill himself. • They engage the police to do it for them.

  20. Suicide by Police • Where does it happen? • Primarily in urban communities where there is a larger population and higher potential for contact. • But could happen anywhere.

  21. Suicide of Police Officer • The numbers of deaths due to suicide are 2 to 3 times the number of line of duty deaths among law enforcement agencies and emergency workers. • Why do they do it? • Shift work and relationships • Apathy from public • Unfair Real World – bad court decisions etc. Not real justice • Constant danger to ones self • Opportunity – all have weapons • More males in law enforcement and more males kill themselves.

  22. The Preliminary Investigation • The first priority is to give aid to the victim if he or she is still alive or to determine that death has occurred. • The dying declaration • Must pass the (3) part test • 1) the declarant must have believed that his death was imminent. • 2) The statement concerned the cause of circumstances of the impending death • 3) the declarant is “unavailable”

  23. Determining that Death Has Occurred • Medically death is determined by cessation of three vital functions: • Heartbeat • Respiration • Brain activity • Failure of the pupils to dilate in reaction to light is a sign of death. • If it appears the victim has just died attempt CPR

  24. The Focus of the Homicide Investigation • After priority matters are completed, the focus of the homicide investgation is to: • Identify the victim • Establish time of death • Establish cause and method used to produce death • Develop a suspect

  25. Identifying the Victim • Usually done by family members, relatives or acquaintances: personal effects, fingerprints, DNA analysis, dental and skeletal studies; clothing and laundry marks or thru missing persons information.

  26. The 26 Stages of Death • Moment of Death:1} The heart stops2} The skin gets tight and grey in color3} All the muscles relax4} The bladder and bowels empty5} The body's temperature will typically drop • After 30 minutes: 6} The skin gets purple and waxy7} The lips, finger- and toe nails fade to a pale color or turn white as the blood leaves.8} Blood pools at the lowest parts of the body leaving a dark purple-black stain called lividity 9} The hands and feet turn blue10} The eyes start to sink into the skull

  27. The 26 Stages of Death • After 4 hours:11} Rigor mortis starts to set in12} The purpling of the skin and pooling of blood continue13} Rigor Mortis begins to tighten the muscles for about another 24 hours, then will reverse and the body will return to a limp state. • After 12 hours:14} The body is in full rigor mortis. • After 24 hours:15} The body is now the temperature of the surrounding environment16} In males, the semen dies17} The head and neck are now a greenish-blue color18} The greenish-blue color continues to spread to the rest of the body19} There is the strong smell of rotting meat20} The face of the person is essentially no longer recognizable

  28. The 26 Stages of Death • After 3 days:21} The gases in the body tissues form large blisters on the skin22} The whole body begins to bloat and swell grotesquely. This process is speeded up if victim is in a hot environment, or in water23} Fluids leak from the mouth, nose, eyes, ears and rectum and urinary opening • After 3 weeks:24} The skin, hair, and nails are so loose they can be easily pulled off the corpse25} The skin cracks and bursts open in many places because of the pressure of Internal gases and the breakdown of the skin itself26} Decomposition will continue until body is nothing but skeletal remains, which can take as little as a month in hot climates and two months in cold climates. The teeth are often the only thing left, years and centuries later, because tooth enamel is the strongest substance in the body. The jawbone is the densest, so that usually will also remain.

  29. Time of Death • Factors that are helpful in estimating time of death are body temperature, rigor mortis, postmortem lividity, appearance of eyes, stomach contents, stage of decomposition and evidence of a change in the victim’s normal routine. • Recent death • A death within 30 minutes is normally the easiest determination to make. The body is still warm, mucous membranes are still moist, blood is still mosist and pupils have begun to dilate.

  30. Death ½ hour to 4 days prior • Mucous membranes are dry • Blood from wounds are dry • Skin blisters are present • Body is slightly pink in Anglo • Body temperature has dropped • Rigor mortis and post mortem lividity are present • Pupils are restricted and cloudy

  31. Hours Postmordum,

  32. Body Temperature • Body temperature drops 2 to 3 degrees in the first half hour after death and 1 to 11/2 degrees each hour after that up to 18 hours. • If the body feels: • Warm and not stiff: Not dead more than three hours • Warm and stiff: Dead between 3 and 8 hours • Cold and stiff: Dead between 8 and 36 hours • Cold and not stiff: Dead more than 36 hours

  33. Rigor Mortis • Rigor mortis is the stiffing of the parts of the body after death because of enzyme breakdown. • The degree of rigor mortis as an indicator of time of death is usually accurate to within four hours when used along with other factors. • Appears in head in 5 to 6 hours • Appears in upper body 12 hours • Appears in entire body 18 hours • Disappears in the same order 36 hours

  34. Postmortem Lividity • Livor mortis, which means literally "the color of death" is the discoloration of the skin caused by flow of blood into the venous spaces under the influence of gravity. Simply put, it is the blood pooling or settling into the lowest portions of the body. • Postmortem livity starts one half hour after death and is congealed in the capillaries in 4-5 hours. Maximum livity occurs within 10 to 12 hours.

  35. Postmortem Lividity www.gary-c-king.com

  36. Examination of Eyes • If the eyes remain open after death, a thin film forms on the surface.  The potassium content from the breakdown of red blood cells enters the eyes and within two to three hours, they look cloudy.  Eyes that are closed develop the same conditions, but it takes much longer: The cloudiness may not occur for an entire day.  This process is not affected by the ambient temperature and some pathologists think that it's a more reliable measure of time of death than the other five.

  37. Examination of Stomach Contents • An examination of the stomach contents, along with the knowledge of exactly when the victim had eaten their last meal, can place the time of death.  Although this is based on an assumption that the stomach digests food and empties into the intestines at a predictable rate, in fact many things can influence this process.  The type of food, the body's metabolizing rate, the presence of drugs or medication, and the person's emotional condition prior to death may all have some effect on how fast food is processed.  Even exercise right before death can slow it down, and the amount consumed.  A light meal may remain about two hours, a heavy meal from four to six hours.  Examination of the small intestine is also done to trace the path of the food.

  38. Decomposition • Immediately upon death, microorganisms that live in the body go to work to dissolve the internal organs.  They produce gas, which bloats the body before it eventually escapes.  The face darkens and liquids escape the nose and mouth.  The tongue swells and the abdomen begins to turn a greenish-yellow color.  Eventually the skin blisters and fills with fluid or gas.  If the weather is warm and humid, putrefaction may set in within a day, but when left in a very cold area or storage space, may be retarded for several months. 

  39. Many Days after Death • It is common knowledge that death attracts insects. What is not common knowledge is that there are scientists called forensic entomologists who specialize in estimating time of death. They do so by estimating what stage of life the insects that inhabit the body are in. Entomologists know which insects are generally the first to arrive, and at what stages of decomposition that other insects will begin to arrive.

  40. The Bug Doctor • The insects that usually arrive first are the Diptera, commonly called "blowflies" and Sarcophagidae, or "fleshflies". In temperate regions, they will usually arrive within fifteen minutes of death. The female blowflies will lay their eggs on the body, especially around the natural orifices. Eggs will also be laid in any open wounds. Fleshflies do not lay eggs, but will deposit larvae. • Little change happens to the blowfly egg in the first eight hours, and total egg stage will typically last about a day. Once hatched, the larvae grow at a predictable rate. The larval stages of development are called instars. Blowfly larvae have three instars. The first instar is approximately five millimeters long after 1.8 days. The second instar is approximately ten millimeters long after 2.5 days, and the third instar is approximately 17 millimeters long after 4 to 5 days.

  41. TIMELINE OF INSECT ACTIVITY 10 minutes : Ten minutes after the body is dead in open air, flies arrive and lay thousands of eggs in the mouth, nose, and eyes of the corpse.12 hours : Eggs hatch and maggots feed on tissues.24 - 38 hours : Beetles arrive and feast on dry skin.48 hours : Spiders, mites, and millipedes arrive to feed on the bugs which are already there.

  42. Effects of Water • A dead body usually sinks in water and remains immersed for 8-10 days in warm water and up to 3 weeks in cold water, it then rises to the surface unless restricted. The outer skin loosens in 5 to 6 days, the nails separate in 2 to 3 weeks.

  43. Gunshot Wounds • Most gunshot deaths result from handguns. • Also be aware of rifles and shotguns. • Knowing the type of weapon is important for making comparison tests and locating unknown weapons. • The major cause of death from gunshot wound is internal hemorrhaging and shock. • The size, number and velocity of the ammunition used and type of weapon determine the effect on eth body.

  44. Gunshot Wounds • Shots fired from a distance produce little or no powder tattooing or carbons on the skin around where the bullet entered. • From 2 feet away tattooing may be present on skin and clothing. • Angle and trajectory can be determined. • Powder tattooing results from both burned and unburned powder.

  45. Powder Tattooing http://www-medlib.med.utah.edu/WebPath/FORHTML/FOR038.html

  46. Powder Tattooing http://www-medlib.med.utah.edu/WebPath/FORHTML/FOR041.html

  47. Contact Wounds http://www-medlib.med.utah.edu/WebPath/FORHTML/FOR020.html Contact Wounds

  48. Contact Wounds http://www-medlib.med.utah.edu/WebPath/FORHTML/FOR020.html

  49. Gunshot Wounds • Entry wounds are smaller than the bullet due to the elasticity of the skin. • Exit wounds are larger than entry wounds. • Exit wounds bleed more as well. • Shogun wounds will be significantly different than handgun wounds.

  50. Stab Wounds • Homicidal cuttings are usually deep, clean cuts without hesitation marks. The wounds may be on various parts of the body. But most often they involve the head and neck. Homicidal slashing wounds may be present. Such a wound may be a single deep cut on the side of the face and neck. Or it may be one of many deep slashes crisscrossing each other.

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