Chp. 2 The Crime Scene Part I 1

Chp. 2 2 Please Do Now #4  Explain what you think happened?  Please write at least 5 lines in your composition book.

Chapter 2: THE CRIME SCENE “ Oh, how simple it would all have been had I been here before they came like a herd of buffalo and wallowed all over it.” —A. Conan Doyle, in The Boscombe Valley Mystery, 1892

Chp. 2 4 Crime solving is a jigsaw puzzle that must be pieced together

Chp. 2 5 Good Investigators Have…  Patience  Thoroughness  Accuracy  Ethics  Respect  Versatility  Objectivity (7)

Chp. 2 6 Complex Reasoning Skills Necessary to Work Through and Solve Crimes:  Deductive and Inductive Reasoning  Classifying  Comparing and Contrasting  Problem Solving  Analyzing Perspectives  Constructing Support  Error Analysis What skills do you think are necessary to work through and solve crimes?

Chp. 2 7 I. Physical Evidence 1.Any object that can establish that a crime has been committed OR 2.Can link a crime and its victim or its perpetrator Its presence first MUST be recognized at the crime scene if it is to be used effectively for aiding the investigator.

Chp. 2 8 Physical Evidence and the Crime Scene Forensic science BEGINS at the crime scene. An investigator must 1)recognize physical evidence 2)properly preserve evidence for lab examination If this is not done, no amount of sophisticated laboratory instrumentation or technical expertise can salvage the situation.

Chp. 2 9 What are CSI Determinations? (6)  What crime has occurred?  Where did it happen?  Who committed the crime?  When was the crime perpetrated?  Why did the crime happen?  How was the crime committed?

Chp CORPUS DELICTI “Body of the Crime”  You 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)

Chp CRIME SCENE TEAM  A group of professional investigators, each 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 Lab Experts: pathologistserologist DNA experttoxicologist forensic odontologistforensic anthropologist forensic psychologistforensic entomologist firearm examinerbomb and arson expert document and handwriting expertsfingerprint expert

Chp CRIME SCENE INVESTIGATION  Based on the scientific method and the Locard Exchange Principle, logic and forensic techniques  **Involves:  Recognition—scene survey, documentation, collection  Identification—comparison testing  Individualization—evaluation and interpretation  Reconstruction—reporting and presenting

Chp Recording the Crime Scene  Investigators have only a limited amount of time to work a crime site in its untouched state  Opportunity to permanently record the scene in its original state must not be lost  Such records will not only prove useful during the subsequent investigation but are also required for presentation at a trial in order to document the condition of the crime site and to delineate the location of physical evidence.  Thoroughly document every step of the investigation with an appropriate method.

Chp PROCESSING A CRIME SCENE 1.Isolate and secure the scene 2.Document the scene 3.Search for evidence 4.Collect and package evidence, maintaining the chain of custody 5.Submit evidence to the crime lab

Chp Crime Scene Management and Processing  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

Chp **5 STEPS OF CRIME SCENE PROCESSING  Each step requires numerous procedures to be performed at certain times: 1.Responding to the crime scene 2.Crime scene photography 3.Crime scene diagramming 4.Collection of physical evidence 5.Processing the scene for fingerprints

Chp Crime Scene Processing Order  Photography  Search and mark evidence  Collection of evidence Hair and fibers Serological specimens Other physical evidence  Fingerprinting  Alternate light sources  Chemical processing  Re-Search  Post evidence recovery photographs

Chp Crime Scene Photography and Diagramming Crime scene photography  completed BEFORE moving or collecting any evidence Crime scene diagramming  The ROUGH SKETCH (with measurements) must be completed BEFORE moving anything and a complete evidence list and sketch legend is completed

Chp Collection of Physical Evidence  The scene must be legally searched for evidence that is both seen and unseen.  When evidence is found, it must be documented fully, collected properly and packaged correctly to maintain its evidentiary value.

Chp Processing the Scene for Fingerprints  Fingerprinting the crime scene is usually performed last. WHY?  Those items or surfaces that need processing will have to be protected from contamination until after the scene has been processed.  There are exceptions to this which are determined by the circumstances of each scene. Fingerprint powders will contaminate the scene

Chp FIRST OFFICER ON THE SCENE  A Assess the crime scene and assist those hurt  D Detain the witness  A Arrest the perpetrator  P Protect the crime scene  T Take notes

Chp 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 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

Chp Record the Crime Scene  **Recording Methods: KNOW 1.Photography (still and sometimes video) 2.Sketches 3.Notes  Ideally all three should be employed  However, personnel and monetary limitations may prohibit the utilization of photography at every crime site

Chp PHOTOGRAPHY  The most important prerequisite for photographing a crime scene is for it to be in an unaltered condition.  Unless there are injured parties involved, objects must not be moved until they have been photographed from all necessary angles.

Chp PHOTOGRAPHY  Photograph physical evidence as it is found, showing its position and location relative to the entire scene  Once overviews are taken, close-ups should be taken to record the details of the object itself.  When the size of an item is of significance, a ruler or other measuring scale may be inserted near the object and included in the photograph as a point of reference. Click for making a photographic record

Chp VIDEOTAPING  Should include the entire scene and the immediate surrounding area  Long shots as well as close-ups taken in a slow and systematic manner  Have one crime scene investigator narrate while another does the actual taping  CANNOT be used in place of still photography

Chp SKETCHES  Once photographs are taken, the crime-scene investigator will sketch the scene.  Rough Sketch —A draft representation of all essential information and measurements at a crime scene. Drawn at the crime scene. It shows all recovered items of physical evidence, as well as other important features of the crime scene.  Finished Sketch —A precise rendering of the crime scene, usually drawn to scale. Not normally completed at the crime scene.  Unlike the rough sketch, the finished sketch is drawn with care and concern for aesthetic appearance.

Chp CRIME SCENE SKETCH Date: August 14, 2005Criminalist: Ann Wilson Time: 11:35 amLocation: 4358 Rockledge Dr, St. Louis, Mo. N

Chp FINISH SKETCHES see figure 2—5 p 48  Made with care and concern for aesthetic appearance - must have information from the rough sketch. WHY?  Computer-aided drafting (CAD) has become a standard method for reconstructing crime scenes from rough sketches (see p. 49 Fig. 4—6) To be admissible evidence in court

Chp Photography and Sketches  4 types of photographs 1.Forensic 2.Medical 3.Evidentiary 4.Police “snap” shots  Sketches Indicate measurements Use only the English system Locate evidence Include date location and case #

Chp NOTES  Note taking must be a constant activity throughout the processing of the crime scene.  Must include a detailed written description of the scene with the location of items of physical evidence recovered.  Must identify:  the time an item of physical evidence was discovered.  by whom.  how and by whom it was packaged and marked.  the disposition of the item after it was collected.  This written record may be the only source of information for refreshing one’s memory in court.

Chp Crime Scene Notes  Concise  Legible  Accurate  Objective (contain no theories, opinions, or speculation)  Are subject to legal discovery  Are legally required in some jurisdictions and must be maintained and surrendered

Chp **DOCUMENTATION**  Notes—date and 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, and a legend (key)  Videography—allows narration (non-subjective) to be included

Chp Please Do Now State 4 factors that determine how a crime scene is searched? State 4 things that an investigator might be looking for at a crime scene. Please list them in your composition book. Photo: evidence-usat_x.htm

Chp CRIME SCENE SEARCH PATTERNS  How to conduct a crime scene search depends on  One person should supervise and coordinate the collection of evidence 1.Location of the scene 2.Time of day / weather 3.Type of crime 4.Details concerning events of the crime 5.Number of people available for the search 6.Available equipment

Chp TYPES OF CRIME SCENE SEARCH PATTERNS  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

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Chp VEHICLE SEARCHES  Hit-and-run cases  Outside and undercarriage of car are examined  Look for cross-transfer of evidence between car and victim (blood, tissue, hair, fibers, fabric impressions, pain, broken glass,…)  Homicide, burglary, kidnapping  All areas of the vehicle, inside and outside, are searched