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									Pathology
               Pathology
• Early forensic scientists were physicians
  who were called upon to give an opinion
  as to the cause of death in individuals.
• Increasingly in the US, medical examiner
  programs are replacing the old system of
  elected coroners, who are not required to
  have training.
                Pathology
• First state medical examiner system was
  established in 1939 in Maryland to assist
  in identification of decent, to determine the
  time of death, to conduct the autopsy, and
  to determine the cause of death.
• These topics comprise pathology.
               Pathology
      Identification of Decedent
• Regardless of who has the ultimate legal
  burden, the coroner or medical examiner
  works with law enforcement personnel &
  others to help identify the bodies of
  deceased persons.
• Few forensic endeavors offer a more
  challenging & creative exercise than
  establishing identification of the living or
  dead.
                Pathology
• Identification is essential to the completion
  & certification of official documents.
• The accurate identification of decedent
  permits certification of death & notification
  of next of kin.
• To facilitate identification of a corpse, the
  following procedures are standard:
              Pathology
          Physical Description
• A basic portrait parle’ of the person should
  be given, much as if describing a living
  person.
• Height, weight, color of eyes, hair, etc.
  should be recorded. Decomposition can
  affect color of skin & hair.
• Skin can blacken to appear Negroid
  instead of Caucasian.
              Pathology
          Physical Description
• Blond hair darkens, while red or brown
  hair tends to become lighter & gray.
• Weight may be overestimated due to
  bloating.
• If hair color is patchy or varies near scalp,
  dying is a distinct possibility & samples
  should be taken for lab analysis.
               Pathology
             Scars & Marks
• Part of portrait parle’ are skin markings –
  birthmarks, scars, etc.
• Tattoos may be especially helpful since
  they may indicate some past experience
  (such as military insignia), or clue as to
  lifestyle (“jailhouse” tattooing), sexual
  preferences, or personal interests, etc.
  including the decedent’s initials or
  someone else’s initials.
               Pathology
             Scars & Marks
• Some tattooed numbers are found such as
  social security, military or prisoner of war.
• Irregular scarring may indicate the former
  presence of a tattoo.
• In case of indistinct tattoos, infrared
  photography, high-contrast photography, &
  computer image enhancement may be
  successful.
                 Pathology
                Fingerprints
• Fingerprinting is still the mainstay of
  identification techniques & the basics of
  taking fingerprints from the deceased in
  various states of decomposition are in
  chapter 5.
• The new AFIS technology makes it
  possible for fingerprint identification to be
  accomplished with increasing speed.
                Pathology
               Photographs
• Entire body should be photographed as
  well as the full face & profile. The profile is
  particularly valuable in recording the
  shape of the ear, feature of the face most
  like a fingerprint, which may be matched to
  authenticated photograph.
• Scars & distinctive features (amputations)
  should be documented. Photos are shown
  for possible identification of deceased.
              Pathology
           Age Determination
• Deceased person’s apparent age may be
  roughly estimated by teeth & in case of
  people under 25 the joining of bones.
• X-rays provide a basis for studying extent
  of cranial & epiphyseal fusions (the uniting
  of various bones serve as landmarks for
  estimating decedent’s age).
              Pathology
            Dental Features
• Pattern of dental work, including plates,
  bridges & fillings can be compared with
  known dental records, plaster olds, & x-
  rays to effect a positive identification.
• Fillings are highly distinctive & can serve
  as an effective means of individualization.
             Pathology
        Radiological Evidence
• The presence of old bone fractures, shown
  in x-rays of the body, sometimes provide a
  positive identification.
• So may surgical pins, plates, pacemakers
  & other implants.
               Pathology
             Blood Factors
• Not only do ABO blood grouping, Rh factor
  & other blood characteristics provide an
  additional means of identification, but DNA
  testing makes the blood evidence
  particularly valuable.
• DNA can also be helpful in instances of
  badly decomposed or skeletonized bodies.
             Pathology
          Medical Indications
• A thorough postmortem examination may
  reveal various diseases or conditions that
  have identification value such as
  hypertension, old strokes, diabetes,
  Alzheimer’s disease & drug abuse.
• Presence of anticonvulsants indicates a
  seizure disorder; antidepressants suggest
  depression, even suicidal circumstances;
  and so on.
               Pathology
              Other Means
• Clues to dead person’s identity may be
  found at scene where body’s discovered
  or personal effects secured by police or
  pathologist.
• Driver’s license or other identification card
  in victim’s wallet or purse may be helpful,
  although mere possession isn’t conclusive.
• Monogrammed personal items (cigarette
  lighter or clothing) may provide clues also.
               Pathology
             Time of Death
• When body is discovered, pathologist or
  medical examiner make observations to
  indicate approximate time of death ASAP!
• The sooner after death body is examined,
  more accurate estimation of time of death.
• Time of death is estimated from changes
  that occur in the body following death.
  They are…
               Pathology
             Time of Death
• Temperature, post-mortem lividity, rigor
  mortis, & putrefaction. Stomach contents &
  ocular changes may also be helpful in
  determining time of death.
• Temperature: rate of cooling depends on
  temperature of air, way body is clothed,
  amount of subcutaneous fat on body.
• Temp averages a drop approx. 1 & ½
  degrees Fahrenheit per hour.
               Pathology
             Time of Death
• Lividity: dark purplish-blue discoloration
  seen on portion of body nearest ground
  caused by blood settling into body’s lower
  parts due to gravity. It can determine if a
  body has been moved after death or not.
• Forearms & lower legs darken due to
  hanging.
• Lividity appears bout 2 hours after death
  when blood tends to clot in tissues.
               Pathology
             Time of Death
• Rigor Mortis: Immediately after death,
  body is limp due to relaxation of muscles
• After death, body begins to stiffen due to
  chemical changes within muscle tissue
  causing rigor mortis beginning at lower jaw
  & neck & spreads downward.
• Time when rigor sets in may be as soon
  as 15 minutes following death or as long
  as 15 hours after death.
               Pathology
             Time of Death
• Average time is 5 to 6 hours after death
  with upper portion of body affected after
  about 12 hours and entire body withing
  some 18 hours.
• Rigor mortis disappears usually within 36
  hours after death beginning again with
  head & neck & proceeding to lower body.
  Disappearance may take from 8 to 10
  hours.
                Pathology
              Time of Death
• Variables that affect speed of rigor’s onset
  & departure include great heat & individual
  differences in muscular development.
• Rough rules generally employed:
  – R.M. should begin within 10 hours after death
  – Whole body should be stiff within 12 to 18
    hours after death
  – Stiffening disappears within 36 hours after
    death
               Pathology
             Time of Death
• Under certain conditions stiffening of
  hands or arms may take place
  immediately after death known as
  cadaveric spasm & frequently confused
  with RM.
• It occurs in cases where great tension or
  excitement precedes death like drowning,
  suicides, homicides.
                Pathology
              Time of Death
• Putrefaction: decomposition changes in
  dead body caused by action of micro-
  organisms (bacteria).
• Characterized by bloating due to gas,
  darkening of face with decomposition
  liquids escaping from nose & mouth,
  tongue swelling, formation of fluid or gas
  filled blisters, green discoloration of
  abdominal skin
                Pathology
              Time of Death
• Temperature can affect putrefaction.
  Further destruction of body is caused by
  maggots & various insects.
• Flies may deposit eggs between eyelids or
  lips or in nostrils within matter of minutes.
  Maggots may develop within 24 hours.
• If temp above 40 degrees Fahrenheit,
  various insects will feed upon the body
  until it is skeletonized.
               Pathology
             Time of Death
• Stomach Contents: can also be used to
  approximate time of death. Emptying rates
  change depending on number of factors
  like type & amount of food, intake of drugs
  or medicine, emotional/medical condition.
• Light meal: about 2 hours; Medium meal:
  about 3 to 4 hours; Heavy meal: about 4 to
  6 hours or even more.
               Pathology
             Time of Death
• Empty stomach means death probably
  occurred a minimum of 4 to 6 hours
  previously. If small intestine is empty as
  well, death probably occurred 12 or more
  hours earlier.
• Ocular Changes: If eyes stay open, a thin
  film may form on the corneal surface in a
  few minutes & cloudiness may take 24
  hours or longer to appear.
               Pathology
             Time of Death
• It is important to remember that time of
  death can only be estimated and that any
  estimate is subject to error based on
  environmental and other variables as well
  as the person determining these variables
  and making the decisions.
                 Pathology
                  Autopsy
• Term postmortem examination refers to all
  procedures followed by coroner, forensic
  pathologist, or other qualified individual in
  conduction a death investigation.
• It includes the preliminary examination,
  identification of the body, photography, x-
  raying, etc. and the autopsy.
               Pathology
                Autopsy
• Postmortem warranted & should be
  conducted in suspected homicide/suicide
• A preliminary examination should be
  conducted by physician in deaths by
  criminal violence, suicides, accidental
  deaths, deaths where no physician was
  present, sudden deaths of a person in
  good health, prison deaths & deaths that
  occur in unusual/suspicious manner
               Pathology
                Autopsy
• When preliminary exam & investigation fail
  to establish clear cause of death, autopsy
  should be conducted.
• General or medical autopsy performed in a
  hospital for purpose of discovering any
  pathological (disease) processes in
  addition to learning the cause of death.
• In contrast, medical-legal autopsy much
  more complete & requires special training
                Pathology
                 Autopsy
• It includes identifying & tagging corpse,
  photo-graphing body dressed & nude; full-
  face & profile portraits; height & weight;
  taking x-rays; examining external body,
  providing detailed description of bruises,
  ligature marks, gunshot or stab wounds,
  etc.; dissection & examining internal body;
  lab testing organs & body fluids for drugs
  & poisons; & rendering opinion, adding
  “cause of death” to death certificate.
              Pathology
               Autopsy
• In actual dissection of body, thoraco-
  abdominal (chest-belly) cavity opened
  most often with Y-shaped incision
  beginning at each armpit area & running
  beneath breasts to lower end of breast-
  bone continuing downward through middle
  of abdomen to pubis.
                Pathology
                 Autopsy
• Next, front portion of ribs & breastbone
  removed as a unit, exposing most of
  organs for examination.
• Next, heart & lungs together with trachea
  & esophagus are taken out.
• Abdomen is given general exam prior to
  removal of organs. Fluids are aspirated
  (drawn out) so they can be analyzed.
                Pathology
                 Autopsy
• Each organ is weighed, examined
  externally, sectioned for internal study.
• Any fluid in thoracic pleural cavity (chest
  lungs) is aspirated for later analysis.
• Tissues from organs are mounted on slide
  for study of cellular changes.
• Contents of stomach are measured,
  recorded, & sampled for toxicological
  analysis.
                Pathology
                 Autopsy
• In pelvic area, genitalia are examined with
  regard to any injury or foreign matter.
  Vaginal & anal swabs are taken during
  external exam.
• Blood, semen, hair samples collected for
  lab analysis. Urine collected from removal
  of bladder so certain drugs that tend to
  concentrate there (Valium & barbiturates)
  my be detected by toxicologist.
                Pathology
                 Autopsy
• Finally, head is examined beginning with
  eyes. To remove brain, incision is made
  across top of head, scalp is pulled forward
  & skull exposed.
• A saw is used to cut through top of skull so
  brain may be examined, removed (after
  various nerves, blood vessels & other
  attachments are cut), weight & section for
  later microscopic review.
               Pathology
                Autopsy
• When finished, large incisions are sewn
  shut. Microscopic specimens are studied,
  chemical analyses are conducted in lab.
• This completes autopsy after which
  medical examiner synthesizes findings &
  attempts to determine “cause of death”
  along with contributing factors.
                   Pathology
                    Autopsy
• Results are presented as formal “autopsy
  protocol”, a legal report & file, typically a folder
  that includes photographs, x-rays, fingerprints, &
  toxicological test results.
• Report includes: external exam (description of
  clothing, description & identification of body),
  evidence of injury (external & internal), central
  nervous system (head & brain), internal exam of
  chest, abdomen & pelvis, toxicology test
  findings, opinion.
              Pathology
            Cause of Death
• For investigative purposes, it is important
  to distinguish between the cause, manner
  & mode of death.
• Cause of death: pathological condition
  producing death (subdural hemorrhage)
• Manner of death: physical agent or
  instrument that was employed (blunt-force
  injury to skull)
               Pathology
             Cause of Death
• Mode of death: indicates intent or lack
  thereof when instrument was used & by
  whom (homicide by person(s) unknown).
• Possible scenario: Cause – myocardical
  infarction (heart attack), manner –
  arteriosclerosis (hardening of arteries), &
  mode – natural.
• 4 modes of death: natural, accidental,
  homicidal & suicidal.
              Pathology
            Cause of Death
• Findings in autopsy are critical in
  determining cause of death. Example:
  Absence of firearm at scene would
  suggest homicide, while presence of
  suicide note would, if proved genuine, be
  an indication of suicide.
• “Psychological autopsy”: investigation of
  decedent’s mental state prior to death
  conducted as aid to determine if suicide
              Pathology
            Cause of Death
• Asphyxia: death caused by lack of oxygen.
  In suffocation, passage of air is block such
  as pillow over face with possible bruises &
  abrasions inside victim’s upper lip.
• Suffocation may be accidental such as by
  food obstruction of which foreign material
  should be revealed during the autopsy.
              Pathology
            Cause of Death
• Deaths by strangulation (when homicidal)
  may be indicated by presence of fingertip
  bruises on neck. Fingernail marks may be
  present in manual strangulation. Ligature
  strangulation will be indicated by presence
  of groove or other marking on victim’s
  throat. At autopsy, strangulation may be
  indicated by fractures of larynx including
  hyoid bone.
              Pathology
            Cause of Death
• In case of asphyxia by hanging, signs of
  violence, particularly about the neck, may
  be an indication of prior strangulation. If
  body is found not to be completely
  suspended, death is probably suicide,
  since murderer would strive to completely
  suspend body. Hanging is common means
  of suicide but is relatively rare as form of
  homicide or accidental death (except in
  the case of children).
              Pathology
            Cause of Death
• Drowning deaths are also due to asphyxia.
  Air in lungs replaced by fluid, so victim
  chokes. Irritation of mucous membranes
  results in formation of great deal of mucus
  in throat & windpipe. Efforts to breathe
  produce a sticky foam which may be
  mixed with vomit. Foam prevents passage
  of air into lungs.
              Pathology
            Cause of Death
• Drowning indicated by presence of white
  foam. Other indicators may be articles
  found grasped in hand & swelling of lungs.
• Asphyxia may be caused by blow to neck,
  (karate chop) or compression of chest
  (pinned under collapsed building). Cherry-
  red lividity may indicate asphyxia by
  carbon monoxide poisoning & can be
  determined by autopsy.
              Pathology
            Cause of Death
• Blunt-force Injuries: usually directed at
  head. Internal organs may suffer without
  external indication of violence. Blows to
  head reveal fracture of skull; chest may
  produce broken ribs that pierce lungs or
  heart or cause heart to be crushed or
  ruptures; blows to abdomen may produce
  ruptured spleen, liver, or kidney & may
  result in death from hemorrhage.
               Pathology
             Cause of Death
• Burning Deaths: by fire typically cause
  corpse to assume a distorted position
  somewhat resembling a boxer’s pose. It
  occurs if person is alive or dead since
  effect is simply contracted muscles. If
  alive, smoke stains around nostrils &
  carbon monoxide in blood. In case of skin
  burned without attendance singeing body
  hair or clothing, scalding by hot liquid or
  steam is indicated.
              Pathology
            Cause of Death
• Electric shock: death by electrocution not
  ordinarily produce a characteristic
  appearance. Pulmonary edema (swelling
  of heart) & appearance of asphyxia may
  be present.
• High voltage electrocution is likely to
  produce visible burns on body, while 1/3 to
  ½ of low voltage electrocutions leave no
  burns.
              Pathology
            Cause of Death
• Gunshot wounds: Bullet wounds two basic
  types: entrance wound & exit wound.
• Entrance wound smaller than exit wound
  as well as rounder & neater with black ring
  of discharge products around edges &
  comparative lack of bleeding.
• Exit wound more ragged in appearance &
  has shredded tissue extruding from wound
  & more profuse bleeding.
              Pathology
            Cause of Death
• Wound Location important. In murder, may
  be found anywhere; in suicide tendency to
  be in right temple, mouth, beneath chin,
  center of forehead, center of back of head,
  or left chest. Majority in right temple, gun
  held tightly against skin to produce star-
  shaped “contact” wound. Presence of
  weapon tightly gripped in hand a strong
  indication of suicide.
              Pathology
            Cause of Death
• Appearance of gunshot wound affected by
  many factors; firing distance, type of
  weapon & ammunition, passage through
  clothing, part of body affected, & factors
  like ricocheting. Distance between firearm
  & wound given by presence of “tattooing”
  or “stippling” (pinpoint hemorrhages from
  discharge of burned gunpowder) indicating
  a relatively “close shot”.
               Pathology
             Cause of Death
• Motor Vehicle Fatalities: traffic accidents
  present special circumstances. Hit & run,
  clothing should be carefully scrutinized for
  grease, tire marks, glass fragments or
  paint. Leg bones are frequently fractured
  by bumper contact & height in relation to
  soles of feet should be measured for
  comparison with forwardmost part of
  bumper.
              Pathology
            Cause of Death
• Trauma associate with driving of vehicles
  having suffered impact may be severe.
• Impacts from front often transversely
  fracture sternum (breastbone) & cause rib
  fractures on sides of chest.
• In young adults, ribs & sternum may be
  unbroken due to relative elasticity, while
  there are crushing injuries to the lungs &
  heart.
              Pathology
            Cause of Death
• Poisoning: murder by poisoning is
  extremely rare. Usually are suicidal or
  accidental & involve narcotic overdoses or
  inadvertent taking of wrong medications.
• Only a few are commonly used for murder.
  Arsenic & antimony most common &
  metallic poisons. Insecticides, rat poisons
  & even certain medicinal preparations are
  used as poisons.
              Pathology
            Cause of Death
• Symptoms of poisoning by arsenic include
  vomiting, cramps, & diarrhea, possibly
  bloody diarrhea. Death may occur in a
  few hours or in several days depending on
  the dosage used – small amounts,
  increasing doses, or a large dose all at
  once.
               Pathology
             Cause of Death
• Arsenic may be detected in body many
  years after death. Detection doesn’t
  indicate murder
• Less commonly used antimony: industrial
  & medicinal (including veterinary) uses.
  Symptoms include intensive gastric
  irritation & pain, metallic taste in mouth,
  vomiting of bloody material, diarrhea,
  sweating, rapid pulse & muscle spasms.
             Pathology
           Cause of Death
• In fatal cases, there may be delirium,
  subnormal temperature & collapse.
• Poisoning may be acute (sudden) or
  chronic (incremental).
• Stabbing: stabbing & cutting wounds may
  cause death themselves or lead to
  complications like tetanus or pneumonia
  that represent a secondary cause of
  death.
               Pathology
             Cause of Death
• Rarely are cutting or stabbing deaths
  accidental; usually they are the result of
  suicide or homicide. In suicide, the left
  wrist, left chest, throat & femoral artery are
  most commonly attacked locations.
• Sometimes wounds accompanied by
  superficial cuts called “hesitation marks”
  (indicating tests before person summons
  enough nerve to inflict fatal slash).
               Pathology
             Cause of Death
• Their presence is strong indication of
  suicide, as is weapon being clenched in
  deceased person’s hands, indicating
  cadaveric spasm. In suicides body
  remains at site of fatal cutting or stabbing.
• In homicide, body may be moved and a
  blood trail of victim attempting to flee
  assailant may be present.
              Pathology
            Cause of Death
• Whereas suicide may be accomplished by
  cutting only, murder has stabbing strokes
  as a means of efficient killing. Fatal
  wounds from homicide usually occur in
  neck or upper chest. Wounds in back are
  indicative of murder. Sometimes victim
  receives cuts on palms or outer forearms
  that result from attempts to wad off attack
  known as “defensive wounds”.
               Pathology
             Cause of Death
• An examination of wounds by medical
  examiner may permit an estimate as to
  type of weapon, its size, shape &
  sharpness.
• The wound dimensions & depth of
  penetration are useful indications of the
  weapon’s characteristics.
             Pathology
      Death of Marilyn Monroe
• Watch Video & Do Video Quiz on the
  Death of Marilyn Monroe.
• After watching video and reading case
  study in book answer the following
  question: Do you think Marilyn Monroe’s
  death was an accidental suicide or a
  homicide? Were the Kennedy’s & or FBI
  involved in your opinion?

								
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