Forensic Death Scene Investigation

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Forensic Death Scene Investigation

• Presented by
• Darrell Thompson
• Chief Forensic Death Investigator
• Tarrant County Medical Examiners District

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DEATH SCENE INVESTIGATIONIntroduction

• Death scene investigation is a crucial part of
  the overall function of the Medical Examiners
  Office. The scene investigation is vital to the
  final ruling as to the cause and manner of death.

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INITIAL REVIEW OF THE KNOWN FACTS

• Interview
• The lead police investigator
• Witnesses
• knowledge of the facts and circumstances prior
  to and leading up to the death

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APPROACH TO SCENE

• Keeping in mind all that has been learned from
  preliminary interviews
• View the overall scene prior to approaching
• Photograph
• Distant photograph depicting the entire scene and
  placement of the body
• Each direction of the compass
• Photograph the body, documenting any item of
  interest that may further the death investigation
  

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APPROACH TO SCENE

• Conduct a detailed inspection of the body and the
  area immediately surrounding the body
• Any possible physical/trace evidence
• Collect and preserve
• Note overall injuries and injury patterns on the
  body
• Match the details learned from the initial
  interviews?
• If not, why?

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APPROACH TO SCENE

• Is this the death scene
• Are there large open wounds and a lack of blood
  at the scene
• Could this death have occurred at a different
  location
• Observation of rigor and livor mortis
• Moved or shifted after death
• All trace evidence should be left in place on the
  body
• Wrap the body in a clean white sheet

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POST MORTEM CHANGES

• Lividity
• Describe in detail
• Location
• Blanchable
• Non-blanchable
• Contact pallor
• Consistent with current position of the body
• Match details learned from preliminary interviews
• Color
• Mottled/patchy

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POST MORTEM CHANGES

• Rigor
• Describe in detail
• Location on body
• Extent of rigidity/breakable
• Consistent with current position
• Consistent with details from preliminary
  interviews

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POST MORTEM CHANGES

• Body temperature
• Temperature to the touch
• Temperature of extremities
• Torso
• Dependent areas

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POST MORTEM CHANGES

• DETAILS THAT MAY AFFECT POSTMORTEM CHANGES
• Ambient temperature
• Disease process (sepsis, seizures)
• Hyperthermia
• Hypothermia
• Drug use
• Physical exercise

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INJURIES AND INJURY PATTERNS

• All readily visible injuries should be noted and
  documented
• Initial inspection, keep in mind
• Preliminary interviews
• Do the injuries correspond to the details as
  furnished by police investigators and witnesses?
  
• Injuries are inconsistent with the known details
• Review findings with the police investigator in
  charge and if necessary
• Re-interview witnesses, in an attempt to
  establish a reason for the inconsistency.
• Note in detail in the investigators report
  unexplained inconsistencies

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INJURIES AND INJURY PATTERNS

• Injuries
• Describe injuries
• Location
• Type
• Blunt force
• Laceration
• Cut
• Gun shot
• Severity
• Distinguishing markings

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INJURIES AND INJURY PATTERNS

• Injury patterns
• Describe patterns
• Associated with weapons, objects, details
• Blood flow patterns
• Note
• Photograph
• Directionality patterns
• Injury
• Bold spatter

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INJURIES AND INJURY PATTERNS

• Document the corresponding
• Objects
• Weapons
• Document details, that may explain the observed
  patterns
• Collect as evidence
• Inspect the clothing for impression/marks
• Transferred by objects located at the scene
• Photograph
• Collect

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MOTOR VEHICLE ACCIDENTS

• Full description of the vehicles
• Damage, severity of damage
• Intrusions into the passenger compartment
• Vehicle structures
• Foreign objects
• Mechanical condition
• Describe all tire marks at the scene including
• Skid/brake
• Straight line from application of brakes
• Yaw
• Curved path faster than the tire can handle
• Scrub
• Irregular at point of impact/immediately after
• Length
• Relation to incident

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MOTOR VEHICLE ACCIDENTS

• Debris pattern
• Impact point
• Gouge marks
• Debris from vehicles
• Dust or dirt dislodged at time of impact
• Seat belt use, type, and condition
• Air bag information/injuries
• Attempt to determine the decedents seating
  position
• Dicing injuries
• Secondary impact points

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MOTOR VEHICLE ACCIDENTS

• Photograph
• The entire accident scene
• Each direction of the compass where possible
• Close ups of the vehicles and decedent(s)
• Interior of the vehicles
• Secondary impact causing visible injuries to the
  decedents
• Motorcycle information
• Helmet

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MOTOR VEHICLE ACCIDENTS

• Charges which may be filed in connection with the
  death
• Are any drugs or alcohol involved in the death

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AUTO PEDESTRIAN

• Injuries and injury patterns
• Consistent with damage to vehicles
• Impact points
• Body/vehicle
• Injury impression pattern
• Suspected point on vehicle that may have caused
  the pattern/injury. (Grill, Emblem, etc)
• Secondary impacts
• Body/head contact with vehicle
• Body with pavement/fixed object
• Consistent with witness statements

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SHOOTING DEATHS

• Location of wounds
• Type of wound
• Powder marks, stippling
• Weapon
• Caliber
• Ownership
• Secondary impact points if the bullet exited the
  body
• Directionality consistent with the known details

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SHOOTING DEATHS

• Ammunition
• Remaining rounds in weapon
• Rotation of cylinder (revolver)
• Live
• Spent
• Under hammer
• Possible blood spatter patterns on weapon
• Consistent with physical evidence and known
  details
• GSR swabbing of shooter/witness
• Protect decedents hands with paper bags

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STABBING DEATHS

• Location of wounds
• Defense wounds
• Attempt to determine the type of weapon used
• Injury patterns
• Blood patterns
• Blood spatters
• Location of initial injury versus location of
  body blood stains in a separate area from the
  location of the body

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HANGING

• Inspect the knot
• Type
• How tied
• Running/fixed
• Point of suspension
• How affixed
• Distance from ground/floor
• Evidence of previous suspensions
• Autoerotic
• Position of body
• Platform

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HANGING

• Autoerotic
• Mirror, positioned for self viewing
• Pornographic material/video
• Failsafe system
• Nudity
• Video camera
• Lingerie
• Evidence of previous suspension
• Position of body
• Contact with floor/ground
• Elevated

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ELECTROCUTION

• Source of power
• Voltage
• Voltage of the available electrical source
• Ground Fault Interrupter
• Equipment
• Power tools
• Extension cord

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ELECTROCUTION

• Equipment
• Assure the power has been turned off
• Closely inspect it for damaged or exposed wiring
• Electrical arcing
• Inspect extension cords
• Location
• Clothing
• Shoes
• Moisture
• Grounding points for the decedent
• Evidence of arcing
• Entry/exit wounds

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FALLS

• Reason for the fall
• Intentional (suicide)
• Slip (accidental)
• Pushed (homicide)
• Details of fall
• Point from which the decedent fell
• Distance to point of impact
• Vertically from point of elevation

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FALLS

• Horizontally from point of elevation
• Any evidence at point of elevation
• Scuff marks
• Signs of struggle
• Point of impact
• Consistent with
• Accident
• Suicide
• Homicide
• Does the scene suggest the injuries are not due
  to a fall?

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BLUNT FORCE TRAUMA

• How injuries may have occurred
• Injuries and injury patterns
• Consistent with any surrounding objects
• Object at the scene that may have caused the
  injuries
• Evidentiary value

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DRUG RELATED

• Drugs or paraphernalia
• Location in reference to death scene
• Possible type of drugs involved
• Collection and preservation
• Evidence on the body that may indicate drug use
• Injection sites
• Indications of inhalation, or huffing

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DROWNING

• Condition of the body
• Discoloration
• Bloating
• Washer woman hands/feet
• Are there visible injuries
• Consistent with details
• Sustained during submersion, or recovery of body
• Body impacting objects in moving water
• Injuries from recovery equipment.
• Details of circumstances surrounding the drowning.

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UNEXPLAINED DEATH

• Unexplained death scene
• Review of the post mortem changes
• Injury patterns
• Scene of death
• Review the immediate area surrounding the body
  for anything which may have played a role in the
  death
• Weapons
• Tools
• Power equipment
• Electrical lines, boxes
• Drugs, paraphernalia
• Possibility of a fall

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UNEXPLAINED DEATH

• The death scene (location where the death
  occurred) should, in most cases, reveal some
  details as to what may have caused the death. A
  close inspection and photography of the scene are
  vital to a successful inquest.

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FINALLY

• There is only one chance to assure a complete and
  thorough death scene investigation.