Homicide Investigation by jennyyingdi


									       Homicide Investigation
JS 112 051710
        Homicide Investigation
• Requires the greatest effort of all major crimes
• Coordinate witnesses, suspect, officers,
  forensic pathologist, criminalists, medical
  examiner etc.
• Many disciplines, attention to detail
• Brings together many concepts of the course
                   Initial Steps
•   Initial focus: Finding the body
•   Rules of first officer on the scene still apply.
•   Find and collect all evidence
•   Determination of suspicious death vs. natural
    causes vs. accident or suicide
          Murder, Suicide or Accident?
• Suspect the worst- Murder
• Murderers have been known to make the death appear to be
  an accident or suicide
• Systematic and accurate investigation can reveal the
• Evaluate the circumstances revealed at the crime scene
• Questions:
   – What was the cause of death?
   – Could the deceased have produced the injuries or brought about the
     circumstances that caused the death?
   – Are there any signs of a struggle?
   – Where is the weapon, instrument or object that caused the injuries
     or traces of the medium that caused death?
              Cause of Death
• The injury, disease, or combination of the two
  which initiated the fatal train of physiologic
  – Multiple Blunt Force Injuries
  – Chronic Obstructive Pulmonary Disease
  – Drowning
  – Undetermined
            Manner of Death
• The fashion in which the cause of death arose.
  – Natural
  – Accident
  – Homicide
  – Suicide
  – Undetermined
Reasons For Determining Cause and

• Innocent exonerated.
• Murder recognized.
• Compile medical evidence for
  civil/criminal matters.
  – Wrongful death suits.
  – Suicide exclusion clauses.
• Recognition of hazards to public health.
                     Cause of Death
• Apparent cause of death vs Actual cause that will be
  determined by the medical examiner
• Determining the cause of death represents a starting point
  and assists in putting facts and circumstances behind the
  death into focus.
• Investigator should have a working knowledge of appearance
  of injuries and wounds in order to take first steps in death
• Erroneous estimate of the cause may lead the investigation in
  a wrong direction and may even jeopardize the ultimate
  solution of the crime
• Experience vs Expertise-
• Cooperation and teamwork with investigator and ME

• Self inflicted injuries or could have deceased brought
  about the circumstances that caused the death?
• Answer based on the evaluation of injuries and
  other factors about the mental and emotional state
  Common modes of death by suicide are drowning,
  hanging, shooting, poisoning, jumping from heights,
  cutting arteries, stabbing and strangulation.
• Detailed examination of the crime scene to
  determine if factors are consistent with suicide
• Think about the 55 gallon gal suicide shown by
                     Suicide (continued)
• Possible suicide
   – Nature and position of injuries
   – Hesitation marks involving wrist slashing
   – Gunpowder tattooing firing at close range
   – Wound location within reach of the deceased
   – In suicides with guns the victim usually drops the weapon or throws it up
     to several feet away
   – No blood on the inside of hands or corresponding parts of the gun grip and
     the rest of the hand blood soaked is usually a good indication that the
     victim fired the shot
   – Dead in a room with door locked from the inside- look for unusual traces
     and marks on doors, locks and latches
• Suspicious death
   – Defense injuries would not be expected on a suspected suicide
   – Blood marks on the hand and grip that do not match
             Suicide (continued)
• Interviews with the deceased’s relative and friends
• Information from physician or psychologist
• History of suicide threats or suicidal tendencies
• Search for suicide notes (55 gallon gal) at the victim’s
  residence and workplace
• Have a qualified document examiner evaluate the
  note for authenticity. Collect handwriting exemplars
  and search for the writing instrument and paper
  used. The document should be examined for latent
             Suicide (continued)
• Motives.
  – Terminal illness
  – Poor financial situation
  – Marital or family problems
  – Psychological problems- Often killing family members
    precedes the suicide- Then it becomes a homicide
  – Inheritance and insurance matters will be influenced by
    the order in which the victims died
  – Sometimes motives are not apparent. So deeply hidden
    they may remain a mystery.
• Obvious signs of struggle
  – Bloodstains- considered the best clues for the
    reconstruction of the course of events
  – Pulled-out hair
  – Overturned or displaced articles of furniture
  – Rumpled rugs
  – Marks of weapons
  – Injuries
               Struggle Bloodstains
•   No bloodstains produced in first stage of attack
•   If victims do not immediately become unconscious at the first blow, stab
    cut or shot it can nearly always be assumed their hands will become
    covered with their blood from touching the injured parts of their body
•   If they attempt to escape or resist, their blood covered hands leave marks
    often indicating their position.
•   After a struggle in a room with furniture a large number of marks of
    bloodstained hands may be found on the legs of tables and chairs.
•   Bloody hair leaves stains on undersides of tables and chairs
•   Bloody imprints on doors, phones, hung up clothers, draperies, curtains
•   Blood spatter on the door- need to note position of the door.
•   Drops of spattered blood can indicate position of a piece of furniture
•   Especially important are footprints in blood (remember the first cold hit
                 Other signs of struggle
• Pulled out hair- certain indication of struggle
• Overturned and displaced furniture
• Chairs, pedestals and other light pieces of furniture fall in the
  direction in which the struggling persons are moving.
• If you suspect a criminal has righted overturned furniture, examine it
  for fingerprints
• Prints on light furniture, its position should be examined as it may
  indicate the furniture was used as a weapon.
• Heavy furniture displaced – marks or scraping indicate displacement.
• Rumpled rugs provide signs of struggle.
• Murder victim may kick floor or furniture and shoes leave marks etc.
         Other signs of struggle
• Marks of weapons
  – e.g. ax swung and scrapes a ceiling or slips
    along a piece of furniture
  – If bloodstained then the blood will be left in
    the shape of the weapon
  – Cartridges, cartridge cases, bullets and bullet
    holes are obvious indications of weapons
• Defense injuries
  – Marks appear to be of a struggle
        Death by violence outdoors
• Not so distinct as indoors
• Fight preceded, ground will be trampled
• Footmarks made with shoes of different sizes and
  appearances or if marks have the form that results from feet
  set down obliquely against the ground indicate evidence of a
• Suicides with hanging, ground may be trampled but marks
  have normal appearance of those of a person walking.
• Struggle outdoors: bloodstains, pulled out hair, marks of
  weapons, resistance injuries, broken twigs, trampled leaves,
  torn-up moss and grass, and footprints where you normally
           Location of Weapon

• Absence of a weapon at the scene indicates murder
• If a weapon or instrument is found then an analysis of
  the situation should be done to provide a preliminary
  decision as to whether it is murder or suicide
• Nothing should be moved or altered
• If evidence might be destroyed, the investigation needs
  to be postponed
• If found, then photograph and describe position
• Pathologist should always be consulted to determine if
  an object can be considered a dangerous weapon
   Examination of a dead body at the
             crime scene
• Before examining the body- Precautions
• Example of officer probed wound with a pencil to
  determine track of a bullet!
• Clothing of victim examined but only visible parts
  before pathologist arrives
• Buttoned, attached, creased, wrinkled, marked by
  injuries, stains, position of clothing, how far pants
  pulled up, garments twisted, inside out.
• Any displacement from normal should be measured.
  Shirts checked for button side right to left or left to
• Check folds. Horizontal or vertical. Due to crumpling of
• When body is dragged, horizontal creases occur that are dirty
  on the outside but clean on the inside folds
• If a body is lifted, characteristic formations are produced.
• If the raised part of a fold is bloodstained but the inner part is
  free from blood, then the position of a part of the body when
  violence was exerted can be determined with certainty
• Damage to the clothes from tearing, crushing, cutting,
  penetration should be measured and documented. At autopsy,
  the damage to the clothes and position of wounds on the body
  can be compared. Important information on the body position
  when the injury was inflicted.
• Stains may consist of blood, semen, saliva, phlegm,
  vomit, feces, urine, dust, dirt or other contamination.
• Document, type, location, size, flow.
• Direction of flow especially strems of blood can
  contribute to the reconstruction of events in death by
  violence. All marks of blood flowing “in the wrong
  direction” should be examined and photographed
• Blood froth when a person continues to breathe after
  blood has penetrated the air passage coming out of
  the mouth and nasal passages
• Estimate blood amount
               Homicide Investigation-
• 1) Confirm the appearance of signs of certain death
• 2) Photograph the body before altered. If already altered, photograph
  then return to original position and photograph
• 3) Preliminary investigation of pockets- ID documents in wallet, purse,
  watch or other valuable articles. Very carefully so original position of
  clothes restored.
• 4) Preliminary sketch of the body position. Marks made at places on
  the floor, top point of the head, ears, elbows, hands, crotch, knees,
  heels and point of toes. Outer contour with chalk
• 5) Position of the body described. In relation to nearest article of
  furniture, object or fixed point. Visible clothing described without
• 6) Detailed examination. Only visible details are examined and
  described. The original position of the body must not be changed
                       Homicide Investigation-Step-by-step
•   7) Head described and examined in relation with respect to the body, eyes and mouth open, color of skin,
    injuries, presence of blood, state of hair, presence of saliva, phlegm, vomit, foreign bodies (soil, sand, vegetable
    matter, hair etc) Direction of flow of liquids should be noted
•   8) Examine the trunk, position, bending or twisting, the position of visible clothing and condition, folds, injuries
    to the body and clothes, presence of blood, saliva semen phlegm, vomit, and foreign bodies.
•   9) Arms and legs examined in the same way as the trunk. Hands should be given special attention. Presence of
    rings, wristwatches, marks left by objects. Foreign objects examined, especially fragments of hair or skin under
    nails. Dirt from under nails collected. If detailed exam cannot be done then enclose the hands in clean paper
    bags tied securely at the wrists. Legs, distance between knees and between heels. Soles of feet or shoes for
    presence of blood and other material
•   10) Course or sequence of events. Consider opinions of others for reconstruction.
•   11) Underside of body and those portions covered by clothes should not be examined at the scene unless done
    in the presence and request of the pathologist.
•   12) After body removed, area under the body should be examined. Critical evidence may be there. Pool of
    blood, bullets, fragments of bullets, projectile… Relationship between location of injuries and bloodstains on
    the floor should be established.
•   13) Body should be transported in the position found if possible. If necessary, clothing can be fixed in original
    position with pins. Moved on clean sheet of cotton or plastic or on an undertakers impregnated paper sheet.
    Protect body from contamination and prevent minute evidence from loss.
•   14) Officer should accompany body to hospital, morgue or autopsy.
                Detailed examination
• Photographs
• Determine entry and exit paths for coroner and check for
• Methodically planned examination with nothing forgotten
• Make accurate notes with details. Never throw away notes
• As far as possible put back into original position. Use chalk
  before moving to mark original position.
• Measurements, as each object is found.
• Shooting, look for weapon, cartridges, cases, bullets.
  Photograph if found. Fingerprints recorded.
           Security concerns
          Outdoor crime scenes
• Difficult to physically secure
• Accessible at many points by many people
• Perimeter may grow beyond original
• As for other scenes, multiple perimeters with
  varied levels of security
• Access strictly monitored and regulated
        Searching an outdoor area

• If no emergency exists (eg bad weather, missing
  child, injured vicitm) time can be taken
• Identify resources and human support needed
• Consider using volunteers with training or experience
  (eg fire departments, emergency response
  personnel, National guard, military)
• Instruct search party as to scope and protocols and
  how to respond if find evidence (Leverite)
• Trained CSI leader should form subgroups and be
  sure single command post gets all info
          Support Equipment for
        Searching an outdoor area
• Support equipment
  – Canines
     • locate missing individuals, dead and decaying remains and objects
       touched by those missing
     • Should be used early as presence of large search parties will
       interfere with tracking
  – Helicoptors
     • Large and/or remote areas
     • FLIR – forward looking infrared detects thermal patterns for living
       or decaying bodies in total darkness
 Communications for Outdoor scenes
• Communications with command center
• Different search groups must communicate
  vital information in timely manner
• Large search parties require many portable
• Cell phones but only in coverage areas (and
  only with a good carrier!)
• If underwater, need trained personnel
            More considerations
            Outdoor crime scenes
• Inclement weather
  – Immediate attention and response to minimize loss or
    destruction of evidence
  – Imprint and blood and trace will be damaged
  – Use tarps to protect
  – Document, preserve and collect if possible without delay
  – Winter conditions may require thaw. Portable heaters and
    tarps can be used to melt ice and snow if needed
 More topics on Outdoor Crime Scenes

• Highways
   – Secondary scenes, dump sites, primary shooting scene
   – Police involved shooting- high profile
   – Difficult to safely secure with high traffic
   – Broken glass, ejected cartridge cases empty pistol
     magazines, imprint patterns
   – Shut down highway if possible. Divert traffic away. Some
     impossible to close, traffic too great and insufficient
     alternate routes
• Hostile crowds
   – Quick, effective documentation (seems like oxymoron)
   – Gather evidence transport to more secure location
      Processing Outdoor scenes
• Perimeter established
• Document before any aspect disturbed
• Map with reference (base or datum point)
• Coordinated can be re-established if needed.
• All evidence taken should include distance and
  compass directions
• Use of GPS with accuracy of a few feet
• Need more precise distances with traditional
    Necessary equipment specific to
           outdoor scenes
• Pruning shears, axes, saws to clear vegetation
• Marking devices or placards mark evidence or areas
  where + metal detector
• String and police line tape- perimeter
• Shovels, hand trowels and rakes- removal of dirt in
  excavation and digging
• Paint brushes-careful removal of dirt in contact with
  buried evidence
• Large buckets to remove soil and debris to other
  areas for further processing
• Sifting screens to search for small objects
   Necessary equipment specific to
     outdoor scenes (continued)
• Evidence bags and boxes- to store evidence recovered
• Portable generators- power for lighting and heating
• Tarps and tents- temporary structures to protect scene
  and evidence
• Mapping equipment- GPS, tape measure, ruler,
  compass and protractor
• Metal detector to detect any small metally objects
• Access to ground penetrating radar
• Communication devices
                  Estimating time of death
• Postmortem signs of death
   – Changes in the eyes- Cornea becomes dull and film may appear over the eye
     within several minutes to a few hours depending on open or shut, temp,
     humidity and air current. Not reliable
   – Temperature of the Body- Rate of cooling depends on factors, temp at time of
     death, environment temp. clothing, surface area to body weight. Core body
     temp considered one of the more reliable. Insert thermometer in liver vs
     ambient temp
   – Rigidity of the body. Immediately after death, the body is flaccid. Rigor mortis
     sets in extremities jaw, fingers first and is complete in 2-6 hours. Remains for 2-3
     days then disappears
   – Lividity: Blood settles to lowest portion of the body due to gravity. Blue or red
     marks on skin. First signs in 1 hour, full development 3-4 hours. Does not form
     on parts exposed to pressure. Can be used to determine if body was moved.
• Decomposition- Autolysis and bacterial action
• Action of insects and animals
 Other indications of time of death
• Stomach contents and intestines
• Watches and clocks
• Conditions
  –   Papers in mailboxes
  –   Food materials state of decomp
  –   Dampness of laundry hung up
  –   Cobwebs
  –   Dates on clendars,
  –   Flowers withering
  –   Growth of vegetation outdoors
• Extent of decay of clothing
  – Cotton decomposes 4-5 years
  – Wool after 8-10 year
  – Leather and silk only after 20 years or longer

• Eyewitness – most common.
• Dental records – very reliable but must have
  antemortem record and be able to find the dentist.
    – Teeth preserved even with trauma, fires, decomposition.
• Fingerprints – reliable if prints on record.
    – AFIS – Automated fingerprint identification system.
•   Tattoos or other external marks (eg. absent fingers).
•   Internal autopsy findings.
•   DNA
•   Circumstances – least reliable.
• In all trauma deaths, the Medical Examiner
  has jurisdiction over the body after death.
• No manipulation of a body after death is
  permissible unless consent is first obtained
  from the Medical Examiner.
• The only exception is Law Enforcement may
  search the body for ID at the scene of an auto
  accident. (Organ Donor)
    Who Can Pronounce Death?
• ANYONE – As long as the person can recognize
• Decapitation
• Decomposition
• Rigor
• Lividity
• Massive Blood Loss
                Livor Mortis
• Gravitational settling of the blood.
• Usually maroon or purplish in color.

• 30 min – 2 hours: Onset
• 8-12 hours: Fixed

• Blanched vs. Non-Blanched
                   Rigor Mortis
• The tightening of the muscles in the body due to an
  increase of lactic acid.

• 0-12 hours: Sets
• 12-24 hours: Remains Set
• 24-36 hours: Resolves

• Starts simultaneously, but is seen first in smaller
              The Autopsy

• Examine clothing and collect trace evidence.
• Collect toxicology, serology, microbiology,
  and special study specimens.
• External examination and x-rays.
• Internal examination.
• Package evidence and take fingerprints.
         Ligature Strangulation
• Death can occur without suspension
• Full suspension
  – Less likely to see petechiae
  – More likely to have fractures
  – Rarely see vertebral fractures
• Horizontal ligature furrow more likely in
• Pure homicidal ligature hanging very rare
•   Green discoloration of lower abdomen
•   Marbling of skin
•   Bloating of body with skin slippage
•   Purge from mouth, anus
•   Disintegration of body
    “The scene will contain
forensic evidence. Identify it,
collect it and preserve it and
  it will speak for the dead”

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