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Eyewitness Basics. Pros & Cons of Testimonial Evidence. Presentation developed by T. Trimpe 2006 http://sciencespot.net/. What is testimonial evidence?.
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Eyewitness Basics Pros & Cons of Testimonial Evidence Presentation developed by T. Trimpe 2006 http://sciencespot.net/
What is testimonial evidence? Testimonial evidence includes oral or written statements given to police as well as testimony in court by people who witnessed an event. Eyewitness accounts can be a useful tool in helping investigators with analyzing a crime scene, but are not viewed to be highly reliable. In addition, eyewitness identifications (right or wrong) can have a big influence on the outcome of an investigation or trial. 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. The Bunny EffectCBS News Video
Memory Challenge Directions: You will have 30 seconds to view the next screen. Try to memorize all 20 items you see! You are NOT allowed to write anything down You CANNOT talk to anyone else.
Items to remember ... Neuroscience for Kids - http://faculty.washington.edu/chudler/puzmatch1.html
What do you remember? You have 2 minutes to list as many of the items as you can! How did you do? All 20 – Awesome 15-19 – Great 10-14 – Pretty swell 5-9 – Could be better 4 or Less – Wake up
Did you know? According to The Innocence Project (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). What factors affect a person’s memory and their ability to identify a suspect? Source: http://www.helium.com/items/1276135-accurate-eyewitness-accounts
Witness Factors • Age may play a role in the accuracy of an eyewitness’ statement or identification of a suspect. Studies have shown that when a lineup contains the actual culprit, both young children and elderly perform well, but when the lineup does not contain the culprit there is a higher rate of mistaken identifications. • The race of the witness may also play a role. The Cross Race Effect (CRE) is a phenomenon in which people are better at recognizing faces of their own race rather than those of other races. • The use of drugs can alter a person’s ability to recall the events of a crime even after they are no longer under the influence. • A person’s memory of an event can be influenced by other witnesses, investigators, and/or the media. Investigators use open-ended questioning and follow procedures for conducting line-ups to limit their influence on a witness’ memory of an event or identification of a suspect. Source: http://www.helium.com/items/1276135-accurate-eyewitness-accounts
Crime Scene & Suspect Factors • A crime that is extremely traumatic for an eyewitness 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 have shown 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. However, body piercings and tattoos increases the likelihood of an accurate identification. • The time of day in which the crime occurred as well as a person’s view of the scene may affect what a he/she is able to see. • In addition, 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. Source: http://www.helium.com/items/1276135-accurate-eyewitness-accounts
Crime Scene Challenge • Now that your eyes and brain are warmed up, let’s test your observation skills a bit more. • 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?
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 Source: http://forensics.rice.edu/html/picture_begin.html
FACES – A software program that offers many options to help you recreate a person’s facial features. Facial Composites Investigators work with sketch artists and eyewitnesses to create facial composites, or sketches of a person’s face. Today many police departments are using facial reconstruction software to help them with this task. The composite may be used internally to assist officers in identifying the suspect or used externally through local media (radio, TV, and newspaper) to solicit leads from citizens.
You will have a chance to try to create a facial composite. You will need to pay close attention to the following features: The shape of the face The shape of the jaw The shape of the eyes The shape of the nose The width of the neck The shape & protrusion of the ears The presence of facial piercing The presence of facial hair, its color, & location The presence of facial markings, such as scars or tattoos Forehead or other facial lines The presence of eyeglasses or sunglasses The length, color, & texture of the person’s hair Let's give it a try!
Forensics K. Davis Crime Scene Processing
Crime Scene • Crime Labs “run” on physical evidence • Physical Evidence = encompasses any and all objects that can establish that a crime has been committed or can provide a link between a crime and its victim or a crime and its perpetrator
Secure and Isolate Crime Scene • Remember- to be effective, evidence must be: • Recognized • Collected and processed properly • Collector must be selective using knowledge of crime lab techniques, capabilities and limitations
Secure and Isolate Crime Scene • Crime labs do not solve crimes • Many jurisdictions have specialized teams to conduct crime-scene searches • Not all crime scenes require retrieval of physical evidence
Evidence Teams • All evidence must be documented in its original state. • It is relatively common for one person to be responsible for two or more aspects of the search.
Evidence Teams • Lead Investigator • Photographer and Photographic Log Recorder • Sketch Preparer • Crime Scene Search Recorder (Note-taker) • Evidence Recorder Custodian • Evidence Recovery Personnel • Specialists
Lead Investigator • the focal point of the crime scene investigation • exerts positive control of the entire crime scene operation • must be able to control actions and access to the scene at all times to insure the investigative efforts are properly coordinated and that the scene is not compromised
Lead Investigator • Assume control—insure safety of personnel and security at scene. • Obtain all preliminary information from the initial responding officer(s) If necessary talk with the complainant to verify information • Determine Boundaries • Establish perpetrator’s path of entry and exit
Lead Investigator • Conduct initial walk-through for purposes of making a preliminary survey, evaluating potential evidence and preparing a narrative description. • Document & photograph obvious items • Brief all team members relative to the scope and purpose of the search.
Lead Investigator • Determine search patterns and make appropriate assignments. • Designate command post location • Insure that sufficient supplies and equipment are available for personnel. • Control access to the scene and designate an individual to log everyone into the scene. • Release the scene after a final survey and inventory of the evidence.
Photographer/Photographic Log Recorder • entire scene (unaltered) including adjacent areas • with overall, medium and close-up coverage • using measurement scale when appropriate • each item of evidence before it is moved to show position and location & close-ups to show detail
Photographer/Photographic Log Recorder • all latent fingerprints, and other impression evidence, before lifting and casting is accomplished • Prepare photographic log and photographic sketch. • Photograph the scene as you left it. • Videography with narration can be used to augment photography.
Sketch Preparer • Diagram a Rough Sketch (at the scene) • Rough Sketch – a draft representation of all essential information and measurements at a crime scene.
Sketch Preparer – Rough Sketch • location of all objects & physical evidence related to the case • legend; coordinate evidence nomenclature with Evidence Recorder/ Custodian and Evidence Recovery Personnel. • accurate depiction of the dimensions showing distance measurements of items using two fixed points • a compass heading designating north
Sketch Preparer – Rough Sketch • indicate adjacent buildings, rooms, furniture, etc., as needed • Designate and label areas to be searched and advise Team Leader and all other search members of nomenclature for designated areas. • Obtain appropriate assistance for taking measurements and list assistant(s) on sketch.
Sketch Preparer • Prepare a Final Sketch (not at the scene) • Finished Sketch – A precise rendering of the crime scene, usually drawn to scale. (usually by professional draftsman)
Sketch Preparer -Finished Sketch • Contains all the information from the rough sketch in a concise, perfected presentation • Often prepared with aid of templates and drafting tools • Often completed using Computer Aided Drafting (CAD) programs
Crime Scene Search Recorder • Note-taking is a constant activity during the crime scene search. • Should include detailed written description of scene • Detailed description of evidence (location of items, time discovered, by whom, how and by whom it was packaged, etc)
Crime Scene Search Recorder • Notes often only written record of details to refresh one’s memory months or years later when at trial • Tape recording or narrating videotape can be advantageous, but still should be transcribed into a written document
Evidence Recorder/ Custodian • Prepare evidence recovery log • Coordinate evidence packaging and preservation • Coordinate evidence nomenclature with Sketch Preparer and Evidence Recovery Personnel • Receive and record all evidence • Maintain chain of custody and control of evidence.
Evidence Recovery Personnel • Have all evidence photographed and videotaped before it is collected • Keep Team Leader apprised of significant evidence located • Initial and date all evidence and turn it over to the Evidence Recorder/ Custodian, after noting where the item was located. • Insure that appropriate safety measures are adhered to, especially with respect to proper protective clothing, including gloves.
Specialists • from industry, the academic community, private scientific labs • Medical Examiner/Coroner- Bomb Engineer • Geologist - Entomologist • Odontologist - Technician • Surveyor - Blood Pattern Analyst • Anthropologist - Crime Laboratory Examiner • Computer Investigative Specialist
Conduct a Systematic Search • Preparation • Approach Crime Scene • Initiate Preliminary Survey • Evaluate Physical Evidence Possibilities • Document Crime Scene • Conduct Systematic Search • Record, Collect, & Process Physical Evidence • Conduct Final Survey • Release Crime Scene
Preparation • Evaluate the current legal ramifications of crime scene searches. (e.g., search warrants) • Fourth Amendment – prohibits unreasonable search and seizure • When time and circumstances permit, obtain a search warrant before investigating and retrieving physical evidence at crime scene.
Preparation - Legal Considerations • A warrantless search may be justified in the following situations: • the existence of emergency circumstances • to prevent the immediate loss/destruction of evidence • search of a person & property within the immediate control of the person provided it is made incident to a lawful arrest • a search made by consent of the parties involved
Preparation - Legal Considerations • Mincey v. Arizona - the 1978 Supreme Court case that related to the impropriety of the warrantless collection of physical evidence at a homicide scene • Michigan v. Tyler - the U.S. Supreme Court decision which dealt with the impropriety of the warrantless collection of physical evidence at an arson scene
Preparation • Accumulate packaging & collection materials • Prepare paperwork needed • Discuss upcoming search with team (b-4 search) • Make preliminary personnel assignments • Organize communication • Organize a “command post”
Basic Premises • The best search options are typically the most time consuming. • You cannot over document the physical evidence. • There is only one chance to perform the job properly.
International Association for Identification Safety Committee Guidelines • Gloves & shoe covers • Liquid repellent coveralls & particle mask/ respiratory, goggles, face shield (when indicated) • Be alert to sharp objects • Use biohazard bags • Note taking done with uncontaminated gloves • No eating, drinking, smoking, etc. at crime scene • Remove contaminated clothing & safety garments immediately (dispose or package for cleaning appropriately) & decontaminate with 10% bleach or antimicrobial soap.
First officer(s) on scene should: • If necessary render aid to the victim(s). • Arrest perpetrator if present • Preserve and protect area as much as possible • Exclude all unauthorized personnel from scene • begin recording who enters and leaves (entry log) • Isolate area using ropes, tape, barricades, guards, etc.
Initiate a Preliminary Survey of Scene • Cautious walk-through of the scene • Acquire preliminary photographs. • Delineate extent of the search area • Organize methods and procedures needed • Determine personnel and equipment needs • Identify & protect transient physical evidence. • Develop a general theory of the crime • Brief team
Evaluate Physical Evidence Possibilities • Based on type of crime, establish evidence types most likely to be encountered • Insure sufficient collection & packaging equipment • Concentrate on the most transient evidence first • Focus first on the easily accessible areas • Look for evidence of “foul play” at the scene
Document the Scene • Documentation of a crime scene is extremely important. The Golden Rule Is; Do Not Touch, Move, Or Alter Any Evidentiary Item Until You Document The Scene. • Notes • Photography/Video • Sketches
Document the Scene - Notes • Accurate & Legible • Facts, observations, and statements; not conclusions or evaluations • Each investigator should keep notes • Purpose • Assist with the preparation of your written reports. • Refresh you memory during the investigation and at trial. • All notes need to be preserved for court.