These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. Lecture 27 Outline of Last Lecture - Types of fingerprints - Recording Prints - Crime Scene Processing - Latent Prints - Patent Prints - Plastic Impressions Outline of Current Lecture - Steps to Examination of a Crime Scene - Roles of the First Responder - Photography and Videography - Notes and Sketches - Crime Reconstruction - Crime Scene Contamination Current Lecture Crime Scene Processing What is a Crime Scene? - Primary Crime Scene - Secondary Crime Scene - Example: Bank robbery - Primary crime scene is bank - Secondary crime scene is getaway car Example - Body found in living room of a house - Primary crime scene - Blood found in victim's car parked in the garage and seat belt is torn - Secondary crime scene ANTH 245 1st EditionWhy Investigate a Crime Scene? - Corpus delicti - Determine what, if any, crime took place - Modus operandi - Determine how the crime occurred - Link people, places, and things - Provide Investigative leads - Prove/Disprove witness statements - Identification of suspects - Identification of unknown substances - Reconstruct the crime Steps to Scientific Examination of a Crime Scene - Recognition - Scene survey - Documentation - Collection and preservation - Identification - Comparison testing - Individualization - Evaluation - Interpretation - Reconstruction - Reporting and presentation Goal of Crime Scene Analysis - Secure, document, collect, and preserve physical evidence related to a crime - Only ONE chance to process the scene properly - Contaminated or poorly documented evidence from the crime scene should be inadmissible in court Roles of the First Responder - Aid victim, if possible- Apprehend suspect, if possible - Identify person who reported the crime and if possible, detain that person - Call appropriate personnel (e.g., detective, crime scene unit) - Secure scene - Keep out non-essential personnel, gawkers, media - Detain witnesses at a scene (keep them separated) - Document all of his/her own actions - Provide "walk-thru" and briefing for arriving specialists - Document personnel present in a log - Establish a secure perimeter (physical barriers) - DON'T TOUCH ANYTHING! Roles of the Principle Investigator - Interview responding patrol officer - Assign duties to other personnel - Interview witnesses and keep them separated - Maintain a secure perimeter - Use markers to indicate evidence to be documented - ONLY person who should talk to the media Photography and Videography - Photography essential - Overall photo of scene(s) showing entire room - Show the relationship of the scene to its surroundings - Mid-range photo showing relationships among pieces of evidence - Close-up photos of evidence (including body) - Photos should be taken from many different angles - Use scales when appropriate - Describe photos taken on a photo log - Videotaping often used but never to the exclusion of photographs Notes and Sketches - Crime Scene Notes- Provides a written record of all activities - Arrival information, scene description, victim description - Note time at which a discovery made and by whom - Can sometimes use a recording device but must transcribe it - Crime Scene Sketch - A simple line sketch of the scene - Can show things photographs cannot (e.g. floor plan) - Add exact dimensions of the scene and relationship of physical evidence to body Evidence Collection - Usually assigned to a single person - Collect the most fragile evidence first - Blood if present, as DNA degrades over time - Tire marks and shoe prints - Collection of: - Control samples if necessary - Sufficient quantities for analysis - Liquids in airtight containers - Place primary containers into secondary containers - Collect and package each piece of evidence separately - Label all evidence with appropriate information; seal it properly - Maintain chain of custody (from collection to deposition in evidence room) Crime Reconstruction - Determine the sequence of events of the crime - Done after documentation of the crime scene and collection of physical evidence - Involves investigators and crime scene analysis - Uses the scientific method - Evidence used: - Eyewitness explanations - Blood spatter and bloodstain patterns - Gunshot trajectory via cartridges, holes in furniture, walls, and victim - Fingerprints - Impressions - Patterns of breakage/burningContamination of Scene - Should be avoided at all costs! - Primary investigator should designate a single route of entry and exit to a crime scene - If something is moved, don't attempt to replace it! Document that it has been moved - Minimize the number of people at the scene - Don't use/flush toilets as this is a primary source of evidence in drug cases/deaths - Don’t' use the telephone found at the scene - Wear personal protective
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