Pathology

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Pathology
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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.

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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.

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PathologyIdentification 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.

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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

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PathologyPhysical 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.

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PathologyPhysical 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.

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PathologyScars 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 decedents initials
  or someone elses initials.

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PathologyScars 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.

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PathologyFingerprints

• 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.

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PathologyPhotographs

• 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.

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PathologyAge Determination

• Deceased persons 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
  decedents age).

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PathologyDental 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.

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PathologyRadiological 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.

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PathologyBlood 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.

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PathologyMedical Indications

• A thorough postmortem examination may reveal
  various diseases or conditions that have
  identification value such as hypertension, old
  strokes, diabetes, Alzheimers disease drug
  abuse.
• Presence of anticonvulsants indicates a seizure
  disorder antidepressants suggest depression,
  even suicidal circumstances and so on.

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PathologyOther Means

• Clues to dead persons identity may be found at
  scene where bodys discovered or personal effects
  secured by police or pathologist.
• Drivers license or other identification card in
  victims wallet or purse may be helpful, although
  mere possession isnt conclusive.
• Monogrammed personal items (cigarette lighter or
  clothing) may provide clues also.

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PathologyTime 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

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PathologyTime 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.

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PathologyTime of Death

• Lividity dark purplish-blue discoloration seen
  on portion of body nearest ground caused by blood
  settling into bodys 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.

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PathologyTime 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.

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PathologyTime 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.

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PathologyTime of Death

• Variables that affect speed of rigors 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

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PathologyTime 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.

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PathologyTime 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

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PathologyTime 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.

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PathologyTime 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.

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PathologyTime 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.

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PathologyTime 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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

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PathologyAutopsy

• 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

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyAutopsy

• 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.

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PathologyCause 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)

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PathologyCause 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.

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PathologyCause 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
  decedents mental state prior to death conducted
  as aid to determine if suicide

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PathologyCause 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 victims upper lip.
• Suffocation may be accidental such as by food
  obstruction of which foreign material should be
  revealed during the autopsy.

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PathologyCause 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 victims throat. At autopsy, strangulation may
  be indicated by fractures of larynx including
  hyoid bone.

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PathologyCause 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).

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause of Death

• Burning Deaths by fire typically cause corpse to
  assume a distorted position somewhat resembling a
  boxers 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause 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.

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PathologyCause of Death

• Arsenic may be detected in body many years after
  death. Detection doesnt 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.

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PathologyCause 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.

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PathologyCause 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).

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PathologyCause of Death

• Their presence is strong indication of suicide,
  as is weapon being clenched in deceased persons
  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.

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PathologyCause 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.

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PathologyCause 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 weapons
  characteristics.

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PathologyDeath 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 Monroes death was an accidental suicide
  or a homicide? Were the Kennedys or FBI
  involved in your opinion?