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    Crime scenes presentation Crime scenes presentation Presentation Transcript

    • Kendall/Hunt Publishing Company
      1
      The Crime Scene
    • Kendall/Hunt Publishing Company
      2
      Corpus Delicti“Body of the Crime”
      Authorities must prove:
      That a crime occurred
      That the person charged with the crime was responsible for the crime
      Top reasons for committing a crime
      Money
      Revenge
      Emotion—love, hate, anger
      Source of evidence
      Body
      Primary and/or secondary crime scene
      Suspect(s)
    • Introduction to Crime Scene Investigation
      • The purpose of crime scene investigation is to help establish what happened (crime scene reconstruction) and to identify the responsible person.
      • carefully documenting the conditions at a crime scene and recognizing all relevant physical evidence.
      • The ability to recognize and properly collect physical evidence is oftentimes critical to both solving and prosecuting violent crimes.
      • It is important to determine the full extent of a crime scene. A crime scene is not merely the immediate area where a body is located or where an assailant concentrated his activities but can also encompass a vehicle and access/escape routes.
      • In the majority of cases, the law enforcement officer who protects and searches a crime scene plays a critical role in determining whether physical evidence will be used in solving or prosecuting violent crimes.
    • Crime Scene Vocabulary
      CRIME SCENE: Any physical location in which a crime has occurred or is suspected of having occurred.
      PRIMARY CRIME SCENE: The original location of a crime or accident.
      SECONDARY CRIME SCENE: An alternate location where additional evidence may be found.
      SUSPECT: Person thought to be capable of committing a crime.
      ACCOMPLICE: Person associated with someone suspected of committing a crime.
      ALIBI: Statement of where a suspect was at the time of a crime.
    • Kendall/Hunt Publishing Company
      6
      Crime Scene Team
      A group of professionals trained in a variety of special disciplines
      Team members
      First police officer on the scene
      Medics (if necessary)
      Investigator(s)
      Medical examiner (if necessary)
      Photographer and/or field evidence technician
      Lab experts
    • Crime Scene Personnel
      POLICE OFFICERS are typically the first to arrive at a crime scene. They are responsible for securing the scene so no evidence is destroyed and detaining persons of interest in the crime.
      The CSI UNIT documents the crime scene in detail and collects any physical evidence.
      The DISTRICT ATTORNEY is often present to help determine if any search warrants are required to proceed and obtains those warrants from a judge.
      The MEDICAL EXAMINER (if a homicide) may or may not be present to determine a preliminary cause of death.
      SPECIALISTS (entomologists, forensic scientists, forensic psychologists) may be called in if the evidence requires expert analysis.
      DETECTIVES interview witnesses and consult with the CSI unit. They investigate the crime by following leads provided by witnesses and physical evidence.
    • Kendall/Hunt Publishing Company
      8
      Crime Scene Investigation
      Based on the scientific method, the Locard Exchange Principle, logic, and forensic techniques
      Involves:
      Recognition—scene survey, documentation, collection
      Identification—classification of evidence
      Individualization—comparison testing, evaluation, and interpretation
      Reconstruction—sequencing events, reporting, and presenting
    • Kendall/Hunt Publishing Company
      9
      Processing a Crime Scene 
      Isolate and secure the scene
      Document the scene
      Search for evidence
      Collect and package evidence, maintaining the chain of custody
      Submit evidence to the crime lab for analysis
    • Kendall/Hunt Publishing Company
      10
      First Officer on the Scene
      A Assess the crime scene and assist the injured
      D Detain the witness
      A Arrest the perpetrator
      P Protect the crime scene
      T Take notes
    • Investigators gather information to:
      Reconstruct sequence of events
      Determine the modus operandi
      MO: the characteristic method of the crime
      Determine the motive of the crime
    • Processing the Crime Scene
      There are 7 steps to processing a crime scene
      Secure and Isolate the Crime Scene
      Record the Scene Photograph, Sketch, Take Notes
      Conduct a Systematic Search For Evidence
      Collect and Package Evidence
      Maintain Chain of Custody
      Obtain Controls
      Submit Evidence to the Laboratory
    • The Crime Scene
      • A place where a crime has taken place.
      • A starting point for a criminal investigation.
      • There is no "crime scene exception" to the Fourth Amendment.
      • That is, once the emergency is over, and police have secured the scene, then the police must comply with Fourth Amendment requirements. 
      • guards against unreasonable searches and seizures
      • requires search and arrest warrants be judicially sanctioned and supported by probable cause
      • If the scene is a protected area such as a house or private part of a business, then a search warrant or consent must be obtained. 
      • Of course officers can secure and protect the scene until these requirements are met (Flippo v. West Virginia).
    • Law Enforcement Personnel on the scene
      • In order for physical evidence to be analyzed and to tell its part of the story, it must first be properly collected.
      • In order for the proper collection to take place, the crime scene, must be properly secured, protected, and preserved.
      • Scene security, protection, and preservation is the responsibility of any and all law enforcement personnel who come in contact with the scene, the suspect, and/or the victim.
    • Kendall/Hunt Publishing Company
      15
      Crime Scene Reconstruction
      Stages
      Data collection
      Hypothesis formation
      Examination, testing, and analysis
      Determination of the significance of the evidence
      Theory formulation
    • Crime Scene Investigation Team
      • Team Leader
      • Photographer and Photographic Log Recorder
      • Sketch Preparer
      • Evidence Recorder/Evidence Recovery Personnel
      • Specialists
    • Team Leader
      Assume control - ensure safety of personnel and security at scene, use of appropriate protective equipment to avoid any health hazard from blood or any other human body fluid.
      Conduct initial walk-through to make a preliminary survey, evaluate potential evidence, and prepare a narrative description.
      Determine search patterns, and make appropriate assignments for team members.
      Designate command post location and ensure exchange of information between search and investigative personnel.
      Coordinate and cooperate with other law enforcement agencies
      Ensure that sufficient supplies and equipment are available
      Control access to the scene and designate an individual to log everyone into the scene.
      Continuously reevaluate efficiency of search during entire course of operation.
      Release the scene after a final survey and inventory of the evidence has been done.
    • Kendall/Hunt Publishing Company
      18
      Crime Scene Survey
      Walk-through—performed by the crime scene investigator, the first officer, and sometimes the lead detective
      Purpose:
      Mentally prepare a reconstruction theory
      Note any transient or conditional evidence that could change over time
      Note environmental and weather conditions
      Note points of entry or exit, as well as paths of travel within the crime scene
      Record initial observations of who, what, where, when, and how
      Identify special needs within the crime scene for personnel, precautions, or equipment and notify superior officers or other agencies
    •                             
                                  
                                  
      Crime Scene Search Patterns
      • Purpose of a search:
      • locate, identify, and collect evidence
      • Standard search patterns used at a crime scene, especially when the scene is very large. These patterns include: spiral, grid, strip or linear, wheel or ray and quadrant or zone search
      • Important things to do during a search:
      • Search from the general to the specific for evidence.
      • Be alert for all evidence.
      • Search entrances and exits.
      • Discuss the search with all personnel.
    • Kendall/Hunt Publishing Company
      20
      Search Methods
      Line or strip method—best in large, outdoor scenes
      Grid method—basically a double-line search; effective, but time-consuming
      Zone method—most effective in houses or buildings; teams are assigned small zones for searching
      Wheel or ray method—best on small, circular crime scenes
      Spiral method—may move inward or outward; best used where there are no physical barriers
    • Kendall/Hunt Publishing Company
      21
      Documentation
      Notes—date, time, description of the location, weather and environmental conditions, description of the crime, location of the evidence relative to other key points, the names of all people involved, modifications that have occurred, and other relevant information
      Photography—photos of scene and surroundings; mid-range to close-up photos with various angles of each piece of evidence; photos as viewed by any witnesses
      Sketches—inclusion of date; time; scale; reference points; distance measurements; names of investigators, victims, suspects; a legend (key)
      Videography—allows for narration (non-subjective) and different perspectives
    • Recording the Crime Scene
      • Documentation
      • transient and conditional details
      • lighting (on/off), drapes (open/closed), weather, or furniture moved by medical teams.
      • The scope extends to possible arguments which might be made in this case (suicide/self defense) and documenting conditions supporting or refuting these arguments.
      • Recognize absence of objects
      • what should be present at a scene but is not (victim's vehicle/wallet) and objects which appear to be out of place (ski mask) and might have been left by the assailant.
    • Photographer/Photographic Recorder
      Photograph entire area before it is entered.
      Photograph victims, crowd, and vehicles.
      Photograph entire scene with overall, medium and close-up coverage, using measurement scale when appropriate.
      Photograph major evidence items before they are moved
      Photograph all latent fingerprints and other impression evidence before lifting and casting are accomplished.
      Prepare photographic log and sketch.
    • Photographing the Crime Scene
      • You can never take too many pictures.  Utilize a flash if necessary.
      • Move evidence for better photographs only after the "as is" photograph has been taken and is necessary for additional identification.
    • Photographing the Crime Scene
      • Digital photography
      • HUGE step and cost effective
      • You can never take too many pictures. 
      • Utilize a flash if necessary.
      • Move evidence for better photographs only after the "as is" photograph has been taken and is necessary for additional identification.
    • Photography and Sketches
      Used together
      Sketched give photographs perspectives
      Help investigators notice and remember details
    • Sketching the Crime Scene
      • Documentation of physical evidence locations, as well as measurements showing pertinent size and distance relationships in the crime scene area.
    • Sketches
      Accurate rough sketch
      All objects should be measured against 2 immovable landmarks
      Label North
      Provide a scale
      ¼ in = x feet
      Anything in vicinity of CS should be included
      Doors, windows, furniture
      Outdoor CS
      Position of trees, hedges, vehicles, other structures
      More accurate sketch needs to be made later to be utilized in court
      Computer programs
      Sketches need to include Case number, date, location, name of investigator
    • Kendall/Hunt Publishing Company
      29
      Crime Scene Sketch
      Date: August 14, 2005 Criminalist: Ann Wilson
      Time: 11:35 am Location: 4358 Rockledge Dr., St. Louis, Mo.
      N
      5 ft
    • Evidence Collector/Custodian
      Have significant evidence photographed before collection.
      Describe evidence and its location on appropriate bag or envelope.
      Sign and date evidence container/maintain chain of custody.
      Appropriately collect and package evidence to maximize evidence integrity.
      Maintain evidence log.
      Use appropriate protective equipment (gloves) and methods when dealing with potentially infective evidence (blood).
    • Collecting Physical Evidence
      • Any collected evidence should have its location and condition documented before it is removed
      • Evidence should be collected in appropriate containers, wearing gloves
      • Containers/envelopes should be sealed with tamper-proof tape
      • Seals should be signed
      • Chain of Custody must be maintained
    • Kendall/Hunt Publishing Company
      32
      Collecting and Packaging Evidence
      One individual should be designated as the evidence collector to ensure that the evidence is collected, packaged, marked, sealed, and preserved in a consistent manner, maintaining the chain of custody.
      Each item must be placed in a separate container, sealed, and labeled.
      The most fragile evidence is collected and packaged first.
      Different types of evidence require specific or special collection and packaging techniques.
      The body is the property of the coroner or medical examiner; collection of evidence on the body is done by that department.
    • Kendall/Hunt Publishing Company
      33
      Packaging
      Most items should be packaged in a primary container and then placed inside a secondary one.
      Pill bottles, vials, manila envelopes, and
      plastic bags are good for most evidence.
      Trace evidence may be placed on a piece of
      paper which is then folded in a particular
      way called a “druggist’s fold.”
      These are then placed inside other containers such as paper bags, plastic bags, canisters, packets, or envelopes, depending on the type and size of the evidence.
    • Kendall/Hunt Publishing Company
      34
      Chain of Custody
      There must be a written record of all people who have had possession of an item of evidence, beginning at the time of collection.
      The evidence container must be marked for identification.
      The collector’s initials should be placed on the seal.
      If evidence is turned over to another person, the transfer must be recorded.
    • Chain of Custody
      • Record of individuals who have had physical possession of the evidence.
      • Documentation is critical to maintaining the integrity of the chain of custody.
      • Maintaining the chain of custody is vital for any type of evidence. In addition, if laboratory analysis reveals that DNA evidence was contaminated, it may be necessary to identify persons who have handled that evidence.
      • Court purposes
      • Need to know who has been responsible for the evidence from the time it was collected to the time it ends up in court
      • Shows:
      • Who collected evidence
      • Who had contact with evidence, at what time, and under what circumstance
      • If any changes were made (if any were at all)
      • Frequently a label on the evidence package itself
    • Information On Evidence Packaging
      • The following information should be included on evidence packaging:
      Location of crime scene
      Location of evidence at scene and time of collection
      Personnel who collected the evidence
      Condition of item at time of collection
      Chain of Custody log
    • Obtaining Controls from the Crime Scene
      • Controls are physical evidence whose origins are known, such as carpet fibers from a suspects home, that can be compared to crime scene evidence.
      • The crime lab must have a thorough sample of control materials for comparison.
    • Submitting Evidence to the Crime Lab
      • Evidence can be submitted to the crime laboratory by a crime scene investigator personally or via the mail
      • Chain of Custody must be maintained at all times
      • Many labs require specific documentation before they will process evidence
      • Evidence evaluated by the lab may take a long time to process, or be held due to back log.
    • Securing and Collecting Evidence
      Evidence must be properly packaged, sealed, and labeled
      Liquids and arsons
      Air tight, unbreakable container
      Biological evidence
      Breathable containers so evidence can dry out
      Prevent mold, kept in freezer
      Placed in Paper bindle
      Bindle placed in plastic/paper container
      Sealed with tape, signature on top
      Evidence log and chain of custody attached
    • Evidence Log
      Contains the following info
      Case #
      Item Inventory #
      Description of evidence
      Name of suspect
      Name of victim
      Date and time of recovery
      Signature of person recovering evidence
      Signature of any witness present during collection
    • Packaging Evidence
      Size of bindle depends on evidence
      Small
      Piece of sheet paper
      Large
      Large sheet of wrapping paper
      Packaging techniques
      Choose appropriate size of sheet paper for bindle
      Crease paper (9 squares)
      Place evidence in center square
      Fold left and right sides in
      Fold in top and bottom
      Insert top flap into bottom flap and tape closed
      Place bindle into plastic or paper evidence bag and fold bag closed
      Place seal over folded edge of evidence bag
      Have collector write their name over the folded edge
      Wet evidence
      Place in paper container and allow to air dry
      Wet evidence should NEVER be packaged in plastic container when wet (any DNA will degenerate and evidence may become moldy and useless)
      Controls must be obtained from victim and crime scene and package accordingly
    • Specialists
      • It is sometimes necessary to bring in expertise from an outside agency.
      • The field of forensic science is so broad today that no agency will have every form of specialty service available from among its ranks.
      • Typically, specialists are brought in from industry, the academic community, private scientific laboratories, and similar concerns.
      • Some items to consider when dealing with outside specialists:
      The competence and reliability of the specialist.
      The ability of the specialist to work at a scene within law enforcement guidelines.
      The role of the specialist in presenting expert testimony in court.
    • Kendall/Hunt Publishing Company
      43
      The Medical Examiner and the Coroner
      A medical examiner is a medical doctor, usually a pathologist, and is appointed by the governing body of the area. There are 400 forensic pathologists throughout the U.S.
      A coroner is an elected official who usually has no special medical training. In four states, the coroner is a medical doctor.
    • Kendall/Hunt Publishing Company
      44
      Medical Examiner’s Responsibilities
      Identify the deceased
      Establish the time and date of death
      Determine a medical cause of death (the injury or disease that resulted in the person dying)
      Determine the mechanism of death (the physiological reason that the person died)
      Classify the manner of death
      Natural
      Accidental
      Suicide
      Homicide
      Undetermined
      Notify the next of kin
    • Cause of death
      •Disease or event (injury) that lead to death
      • What process led to death
      • Any injury that causes a pathological alteration or condition in the body that leads to death
      • Ex. Blunt force trauma to the head, gunshot wound to the thorax
      Mechanism of death
      • biochemical or physiological changes that lead to the individual dying
      • asphyxiation, hemorrhaging, intoxication, infection, arrythmia
      Manner of death
      • Why the cause of death came to be
      Natural
      Accidental
      suicide
      homicide
      undetermined
    • Kendall/Hunt Publishing Company
      46
      The Corpse
      “The way I see it, being dead is not terribly far off from being on a cruise ship. Most of your time is spent lying on your back. The brain has shut down. The flesh begins to soften. Nothing much new happens, and nothing is expected of you.”
      —Mary Roach, Stiff, W. W. Norton & Company, 2003
    • Kendall/Hunt Publishing Company
      47
      People in the News
      Dr. Michael M. Baden is a renowned pathologist and was the Chief Medical Examiner in New York City and for Suffolk County.
      Dr. Baden was on the panel that investigated the assassinations of president
      John F. Kennedy and Dr. Martin Luther King, Jr. He has been involved as an expert
      in forensic pathology in many cases of international interest, including:
      The remains of Tsar Nicholas of Russia and his family
      The Claus von Bülow murder trial
      Expert witness for the defense in the O. J. Simpson trial
      Reautopsy of Medgar Evers, civil rights leader
      Reexamination of the Lindbergh kidnapping and murder
      Autopsies of the victims of TWA Flight 800
      Dr. Baden is the host of HBO’s Autopsy series and is featured on many of the crime talk shows.
    • Crime Scene Investigation
      • Scientific method
      • Locard Principle
      • Logic
      • Forensic techniques
      • Investigators must:
      • Process crime scene, recognize and document the scene, collect evidence
      • Identify and classify evidence
      • Individualization is always the goal
      • Uses comparison testing, evaluation, and interpretation of evidence
      • Reconstruct the crime scene
      • Determine sequence of events
      • Report and present all findings
    • Crime Scene Investigation Projects
      Synopsis of the crime
      Date
      Location (general and specific)
      Time
      People/witnesses
      Victim
      Suspects
      Manner and Mechanism of Death
      City/Town/Department investigating
      Weapons (if any)
      Any other relevant information
      Creative story re-creating the crime
      Sketch of the Crime Scene(s)
      Key Evidence Collected (classify)
      Transient/conditional evidence
      Units used (or should have been used) to analyze evidence
      Explanation as to how the crime scene was “botched”
      Analysis of how the crime scene should have been processed
      Crime Scene search pattern that was used (or should have been used)
      Pictures (victim, suspects, crime scene, evidence)
      Outcome of the case
      Groups of 3-4
      Piece of Paper, Group members names
      and Case #_____
      The Manson murders
      The OJ Simpson Case
      The Enrique Camarena Case
      The JonBenet Ramsey Case
      The Jeffery MacDonald Case
      The Sir Harry Oates Case