What is testimonial evidence?

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2 What is testimonial evidence? Includes oral or written statements given to police as well as testimony in court by people who witnessed an event. Not viewed as highly reliable. People are likely to view the same scene in different ways depending on their positions, line of sight, familiarity with the area, and other factors that can interfere with a person s ability to remember details.

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4 Did you know? According to The Innocence Project in 2008, "Eyewitness misidentification is the single greatest cause of wrongful convictions nationwide, playing a role in more than 75% of convictions overturned through DNA testing." Still, the criminal justice system profoundly relies on eyewitness identification and testimony for investigating and prosecuting crimes (Wells & Olson, 2003).

5 Crime Scene & Suspect Factors In Witness Accuracy: A crime that is extremely traumatic may affect his/her recall of the event. For example, a witness confronted with a weapon tends to focus on the weapon rather than the perpetrator s face. Someone who is able to focus on a perpetrator's face for a minute or longer will tend to have a more accurate memory than someone who saw the person for only a few seconds. Studies show that faces that are either highly attractive, highly unattractive, or distinctive are more likely to be accurately recognized. Simple disguises, such as hats or sunglasses, can interfere with accurate eyewitness identification. Body piercings and tattoos increases the likelihood of an accurate identification. The time of day in which as well as a person s view of the scene may affect what a he/she is able to see. A person who is familiar with the area in which the crime took place, may have a better recall of the positions of the victims or suspects.

6 Witness Factors in their own accuracy: Age may play a role in the accuracy of an eyewitness statement or identification of a suspect. The race of the witness may also play a role (Cross Race Effect). The use of drugs can alter a person s ability to recall the events. Other witnesses, investigators, and/or the media can influence memory.

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8 Crime Scene Challenge Let s test your observation skills a bit. You will have 2 minutes to study the photograph of a crime scene on the next slide. Try to pay attention to details as you will be asked 10 questions about the crime scene! You are not allowed to write anything down until after the time is up. Ready?

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10 Answer each question below. 1. What color coffee mug was in the picture? Blue Red Yellow 2. When was the deadline? Yesterday Today Tomorrow 3. What time was on the clock on the wall? 10:40 11:05 1:55 4. How many sticky notes were on the whiteboard? Four Six Eight 5. Which of the following was NOT in the picture? Stapler Trash Can Printer 6. What was the name on the plaque on the desk? Bill Brian Carl 7. What color was the victim's shirt? Black Blue Red 8. How many plants were in the picture? None One Two 9. What was the color of the marker in the desk drawer? Red Blue Green 10. Where was the book in the picture? On a box In the trash can Under the body

11 So, why do we need physical evidence? Because witnesses are not as reliable.

12 What will evidence collected at a scene do for the investigation? May prove that a crime has been committed. Establish key elements of a crime. Link a suspect with a crime scene or a victim. Establish the identity of a victim or suspect. Corroborate verbal witness testimony Exonerate the innocent. Give detectives leads to work with in the case.

13 Primary Crime Scene Personnel Police Officer Basic role is public safety. They are typically the first responder. Make arrests / Detaining persons of interest in the crime. Calling in EMTs. Taking statements from witnesses. Securing the scene so no evidence is destroyed. Crime Scene Tech: Shift Work. Not 8 5. Documents the crime scene in detail and collects any physical evidence. Detective (Primary Investigator): Responsible for entire scene investigation. Interviews witnesses and consults with the CSI unit. They investigate the crime by following leads provided by witnesses and physical evidence. Laboratory Personnel: 8 to 5 work. Most work done in the lab.

14 Secondary Crime Scene Personnel DISTRICT ATTORNEY Is often present to help determine if any search warrants are required to proceed and obtains those warrants from a judge. MEDICAL EXAMINER / CORONER (If a homicide) may or may not be present to determine a preliminary cause of death. SPECIALISTS Forensic entomologists, anthropologists, or psychologists. May be called in if the evidence requires expert analysis.

15 In order to get these jobs: Background investigation (on you). Interview. Polygraph test. Financial check.

16 First Responders

17 When approaching a crime scene a responder has 3 prime considerations: Personal Safety and the well being of victims. Preserving and Isolating the crime scene. Recording the crime scene.

18 Tasks of the first responder: Initial Response - Beginning recording time-related events. Safety - Identify threats (suspect lose, drug lab present) Emergency care - Direct EMTs to prevent destruction of evidence. The first priority should be given to obtaining medical assistance.

19 Secure and Control people at the scene: NOBODY GOES IN UNLESS THERE IS AN IMPLICIT PURPOSE FOR THEIR PRESENCE!! Exclude and separate suspects, witnesses, family, nonessential personnel. Preserve & protect the crime scene to the greatest extent possible. Call for back-up / investigative personnel. Establish the boundaries of the crime scene. Identify the entry and exit of the suspect. Keep a written log of who enters and exits the scene & when they do so. Consider whether you need to get a search warrant.

20 The Investigator or Detective

21 Good Investigator/Detective Qualities: Patience Thoroughness Accuracy Ethics Respect Versatility Objectivity

22 First steps for the Investigator: Debrief with the first responders. Evaluate safety (broken gas line, hazmat issues). Search and seizure issues (do you need a warrant?). Look at your path of entry into the scene. Does it protect the evidence? If not, do you need to change it? Evaluate the scene boundaries. Go bigger or smaller? Do you have multiple scenes? Continued scene integrity.

23 First steps for the Investigator: Establish the incident command center. Establish a temporary evidence storage area. Consider if you have enough help. Do you need the medical examiner? Are there federal agencies that may need to be called? Identify witnesses, and separate them. Canvas the surrounding area around crime scene. Surveillance equipment may have a picture of the perpetrator. Dumpsters or garbage cans where evidence could have been dropped? People nearby who may have witnessed something? Take the preliminary photos of the scene.

24 Locard s Exchange Principle Edmond Locard ( ) Eatablished the first crime scene laboratory in Lyon, France (1910) When a suspect comes in contact with an object or person, a cross transfer of evidence occurs.

25 Crime Scene Management and Processing means: The crime scene must be identified. The scene must be secured. Access and departure must be logged. Access must be restricted to authorized personnel. A chain of custody MUST be established for every piece of evidence from collection to inspection.

26 Crime Scene Protocol Step 1: Interview Interview the first officer at the scene or the victim to determine what allegedly happened, what crime took place, and how was the crime committed. This information may not be factual information but it will give the investigators a place to start. Step 2: Examine This will help identify possible evidence, identify the point of entry and point of exit, and outline the general layout of the crime scene. Step 3: Document Involves creating a pictorial record of the scene as well as a rough sketch to demonstrate the layout of the crime scene and to identify the exact position of the deceased victim or other evidence within the crime scene. Step 4: Process The crime scene technician will process the crime scene for evidence, both physical and testimonial evidence. It is the crime scene technicians responsibility to identify, evaluate and collect physical evidence from the crime scene for further analysis by a crime laboratory.

27 Step 1: The Interview Talk to everyone who was at the crime scene before you were. Document what is said and done before you assumed control.

28 Step 2: Examine Take a long detailed look at the scene in phases: 1. Survey. 2. Walkthrough. 3. Assign Tasks.

29 Surveying the Crime Scene Once secured, the lead investigator gets an overview of the scene and develops a plan for the systematic examination and documentation of the crime scene.

30 The Walk-Through: Perpetrator s entry and exit path should be established. Focus on these key points. Investigators should follow an indirect path to the center of the scene. Investigators must document and photograph obvious items.

31 The investigator should ask the following questions (when considering how best to process the scene): Is the scene indoors or outdoors? What is the location of the scene (street address)? What are the weather or temperature conditions? What type of building or neighborhood is the scene located in? Was there an odor detected upon the arrival of the first responder? Are doors or windows opened or closed? Locked or unlocked? Is anything damaged, out of place, or missing? Does the scene appear to involve violence? Are there objects that do not appear to belong there? Does on object s condition suggest that a struggle took place? Are lights or electrical appliances on or off? Is food present? Is it in the middle of being prepared, partially eaten, etc.? Contents of ashtrays, trash cans? Are there tooth marks or lipstick on objects? What is the state of the bathroom? Are towels dry or wet? Toilet seat up or down? Any places where the suspect could have quickly and easily hidden a weapon? Is a vehicle nearby? Is the engine hot or cold? Items that might suggest the timing of the incident (newspaper dates etc.). Presence or absence of evidence may suggest whether the scene is the primary or secondary scene (missing TV, baby toys in a house without a baby).

32 What evidence would you collect?

33 Assign Tasks (to be carried out in this order): Locating possible evidence. Assessing the evidence. Processing the evidence (taking prints off of objects).

34 Searching the Crime Scene: How someone carries out the search depends on the locale, size of the area, actions of suspects and victims.

35 Types of search patterns: Line Search Pattern 1 or 2 investigators. Start at the boundary at one end of the scene and walk straight across to the other side. Then move a little farther along the border and walk back in the other direction. Grid Search Pattern 2 or more people. Perform line searches that originate from adjacent corners and form perpendicular lines. Very thorough but boundaries must be well established.

36 Types of search patterns: Spiral Search Pattern Usually 1 person. Investigator moves either in an inward spiral from the boundary or in an outward spiral from the center. Inward works well because you are moving from an area that is light in evidence to an area that is heavy in it. Wheel / Ray Search Pattern Employs several people. Move from the boundary straight toward the center. Not most preferable because it leaves space between the rays.

37 Types of search patterns: Quadrant/Zone Search Pattern Several people. Involves dividing the scene into zones or quadrants, and team members are assigned to search each section. These can be subdivided for smaller teams within the original team. Best suited to large areas.

38 Types of search patterns: Vehicle Searches At all times investigators must avoid contact with all surfaces. In hit-and-run cases, the outside and undercarriage must be searched as well. In theft or burglary, the focus is on the place of entry (tool marks, fingerprints. In the case of crime transportation (getaway, moving body) the interior gets more attention.

39 Types of search patterns: Night Searches When possible, the area should be taped off and searched in daylight. Leave undisturbed and guarded until the next day. When this cannot wait, the boundaries should be taped off and floodlights set up prior to the search.

40 Locating Evidence What to search for will be determined by the circumstances of the crime. THIS MAY INCLUDE: Footprints, Weapons, Blood spatter, Objects possibly touched by the suspect, Trace fibers or hair.

41 Locating Evidence Special attention should be paid to the body and the area surrounding it. When an investigator finds something of possible evidentiary value, they should: Record its location in the notes, Record it in the sketches, Document with photographs, Mark its location with an evidence marker.

42 The search ends when the lead investigator determines that all of the evidence has been located to the best of the team s ability. When this is determined the following happens: Conduct a visual overview of all parts of the scene. Inventory of all evidence collected. Collect and clean up equipment. Ensure all threats at the scene have been dealt with properly. Scene is released to the proper authorities.

43 Step 3: Document Key step that always gets overlooked. EVERYTHING has to be recorded correctly for future reference. Also useful in refreshing your memory before testifying in court. Three primary methods of crime scene recording: Notes Photographs Sketches

44 Step 4: Process Perhaps the most challenging skill of the crime scene technician is the recognition of the probative value of evidence. Probative means to help answer an unknown fact. Don t squander the resources of the laboratory on evidence that does not matter. Evidence that really should not be collected for later analysis: Blood from a pool under the victim This is most likely the victim s. Hair and fiber analysis from the victim s home (simply for identifying the victim). Why? It is their home. GSR Testing 99% of all GSR testing is nonprobative. A person can test positive if they were near someone who fired a gun, or passed through the area at some point afterward.

45 Evaluation of evidence How will you collect it? Have a plan BEFORE you collect it: Focus on the easy to access evidence first, then work on the most difficult. Collect a footprint before a blood spatter that requires a ladder to reach. Move from the least intrusive collection process to the most intrusive. Processes that might destroy evidence should be last collecting blood samples comes after blood spatter photos. Assess environment for changes. Outdoor scene where a snow storm is moving in. There is a potential for multiple scenes (evidence from one may be important at another. You have the bullet casings at your scene, and there is a gun in a car at another scene. Identify alternate methods of collecting evidence.

46 Debrief: Crime Scene Closeout: Include all relevant personnel. Including legal counsel. Also, first responders. Determine what you collected. Did you get everything? Is everything accounted for? Does it correspond with the chain of custody? Were there any mistakes made? Acknowledge it and fix it. Discuss preliminary findings. Discuss any possible testing and the sequence of testing on evidence. Consider the probative value of each item. Initiate any actions you determine and they should be documented. Brief the person in charge. Hopefully they will be in the debrief meeting. Determine post crime scene responsibilities.

47 Perform Final Scene Survey. Everyone needs to look at the scene one last time, to find any evidence that may have been missed. Double check your evidence collected and chain of custody and documentation. Clean up and remove all equipment and trash. Release the crime scene. Assemble all documentation to a single file: First responder s report, any EMT reports. All photographs and videos. All crime scene sketches and diagrams. All evidence documentation - Your notes & Chain of custody documentation. Reports from any other responders: medical examiner lab reports (toxicology, DNA, Odontologis, Anthropologists, etc.). Copy of warrant for searches.

48 Crime Scene Processing Order 1. Photography 2. Search and mark evidence 3. Collection of evidence 1. Hair and fibers 2. Serological specimens 3. Other physical evidence 4. Fingerprinting 5. Alternate light sources 6. Chemical processing 7. Re-Search 8. Post evidence recovery photographs

49 Common Types of Physical Evidence: Blood, Semen, and Saliva Documents Drugs Explosives Fibers Fingerprints Firearms and Ammunition Glass Hair Impressions Organs and Physiological Fluids Paint Petroleum Products Plastic Bags Plastic, Rubber and other Polymers Powder Residues Serial Numbers Soil and Minerals Tool Marks Vehicle Lights Wood and Other Vegetable Matter.

50 Handling Evidence: Investigators should handle and process physical evidence in a way that prevents any change from taking place between the time it is removed from the crime scene to the time when it is examined at the crime lab. Changes can arise from: contamination, breakage, evaporation, scratching, bending, careless packaging. Trace evidence should not be removed from the items that bear them. Instead, the entire object should be sent to the lab for processing.

51 Packaging Evidence: Sealable containers should be used when evidence can be lost through evaporation (ie. Petroleum fumes on items) Small trace evidence can be placed into a piece of paper folded with a druggists fold. Each item from each area gets is own packaging, preventing cross contamination from different areas. Biological materials: Should not be stored in an air-tight container (mold growth). Should be air dried, then stored in individual wrapping paper, manila envelopes, paper bags. Handled by a minimum of personal contact and should be assumed to be infectious. Gloves should be worn and changed frequently. DNA Evidence Likely sources of DNA evidence include stamps, envelopes, cups, cans, chewing gum, cigarettes, sweatbands, hats and bedsheets (to name a few). Contamination can occur through coughing or sneezing onto evidence, when evidence is incorrectly placed in contact during packaging.

52 Maintaining the chain of custody: Whenever evidence is presented in court as an exhibit, the investigator must establish continuity of possession. This means he must account for every person who handled it. Once an investigator selects a container, they must mark it for identification. Sealed with evidence tape at the opening and labeled. The investigator who packaged the evidence must write his initials and date on the tape. A minimum record of evidence would show the collectors initials, location of evidence, and date of collection. Transfer of evidence to another individual or delivery to the crime lab must be recorded in the notes and other forms.

53 Obtaining Standard / Reference Samples: When examining evidence (soil, blood, etc) the scientist must often compare it to a reference sample. It is a good idea to collect these when other samples are taken (victim s or suspects hair or DNA sample). Some types of evidence must be accompanied by substrate controls. These materials are located close to where physical evidence has been deposited. Submitting Evidence: Evidence can be submitted in person or by mail. Some labs require evidence to come with an evidence-submission form. Once evidence has been tested, it can be submitted to long-term storage.

54 Ensuring Crime Scene Safety OSHA requires that law enforcement agencies offer free Hep. B vaccinations to anyone who may have contact with bodily fluids. The International Association for Identification s Safety Committee has proposed the following guidelines: A minimum of latex gloves and protective shoe covers. When potentially infectious dust or mist may be encountered, a particle mask/respirator may be used. When infectious materials are present, a red biohazard bag should be maintained for the disposal of gloves, clothing, masks, etc. Note-taking should be done while wearing clean gloves. If protective wear becomes soiled or torn, it must be removed immediately & the contaminated body areas should be decontaminated with 10% bleach. Eating, drinking, smoking and application of make-up are forbidden at the crime scene.

55 Releasing the Scene When EVERYTHING you need to do is done, and all possible evidence has been collected, you can release the scene.