Forensic Death Scene Investigation

1. Forensic Death Scene Investigation Presented by Darrell Thompson Chief Forensic Death Investigator Tarrant County Medical Examiner’s District

2. DEATH SCENE INVESTIGATIONIntroduction Death scene investigation is a crucial part of the overall function of the Medical Examiner’s Office. The scene investigation is vital to the final ruling as to the cause and manner of death.

3. 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

4. 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

5. 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?

6. 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

7. 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

8. POST MORTEM CHANGES • Rigor: • Describe in detail • Location on body • Extent of rigidity/breakable • Consistent with current position • Consistent with details from preliminary interviews

9. POST MORTEM CHANGES Body temperature: • Temperature to the touch • Temperature of extremities • Torso • Dependent areas

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

11. 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 investigator’s report unexplained inconsistencies

12. INJURIES AND INJURY PATTERNS • Injuries: • Describe injuries • Location • Type • Blunt force • Laceration • Cut • Gun shot • Severity • Distinguishing markings

13. INJURIES AND INJURY PATTERNS • Injury patterns: • Describe patterns • Associated with weapons, objects, details • Blood flow patterns • Note • Photograph • Directionality patterns • Injury • Bold spatter

14. 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

15. 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

16. 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

17. 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

18. MOTOR VEHICLE ACCIDENTS • Charges which may be filed in connection with the death • Are any drugs or alcohol involved in the death

19. 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

20. 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

21. 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 decedent’s hands with paper bags

22. 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

23. 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

24. 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

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

26. 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

27. 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

28. 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?

29. 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

30. 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

31. 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.

32. 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

33. 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.

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