1 Forensic Science Fundamentals Investigations 2 e Chapter

Chapter 2 Vocabulary o o o o 2 chain of custody circumstantial evidence class

Principle of Exchange o Locard's Principle of Exchange • • 3 When a person

Types of Evidence o Direct evidence • o Circumstantial evidence • 4 First-hand observations

5 Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western

Types of Evidence (continued) o Class evidence • o Individual evidence • 6 Narrows

The Crime-Scene Investigation Team o o o 7 Police officers Crime-scene investigators Medical examiners

The Seven S’S of Crime-Scene Investigation 1. 2. 3. 4. 5. 6. 7. 8

9 Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western

Packaging Evidence o 10 The paper bindle is ideal packaging for small, dry, trace

Chain of Custody 11 Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All

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Mapping the Outdoor Crime Scene o 13 Datum Points and Subdatum Points Forensic Science:

Mapping the Outdoor Crime Scene (continued) o 14 Marking Evidence Collecting Limits Forensic Science:

15 Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western

16 Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western

Mapping the Outdoor Crime Scene (continued) o 17 Measuring and Marking Evidence Positions Forensic

Analyze the Evidence o 18 Forensic lab technicians are specialized to process only one

Crime-Scene Reconstruction o Crime scene reconstruction involves: • • o 19 Forming a hypothesis

Staged Crime Scenes o Commonly staged types of crime scenes include: • • •

Summary o o o 21 Locard’s Principle of Exchange states that contacts between people

Summary (continued) o o o 22 A crime-scene investigation team consists of police officers,

Summary (continued) o o 23 After examining the crime scene(s) and identifying evidence, the

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Chapter 2 Vocabulary o o o o 2 chain of custody circumstantial evidence class evidence crime-scene investigation crime-scene reconstruction datum point direct evidence o o o o Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 first responder individual evidence paper bindle primary crime scene secondary crime scene trace evidence triangulation All rights Reserved Cengage/NGL/South-Western © 2016

Principle of Exchange o Locard's Principle of Exchange • • 3 When a person comes in contact with an object or another person, a cross-transfer of physical material can occur. The intensity, duration, and nature of the entities and contact determine the extent of the transfer. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Types of Evidence o Direct evidence • o Circumstantial evidence • 4 First-hand observations Indirect evidence that can be used to imply a fact but that does not prove it Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Types of Evidence (continued) o Class evidence • o Individual evidence • 6 Narrows an identity to a group of persons or things Narrows an identity to a single person or thing Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

The Crime-Scene Investigation Team o o o 7 Police officers Crime-scene investigators Medical examiners Detectives Specialists Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

The Seven S’S of Crime-Scene Investigation 1. 2. 3. 4. 5. 6. 7. 8 Securing the Scene Separating the Witnesses Scanning the Scene Seeing the Scene Sketching the Scene Searching for Evidence Securing and Collecting Evidence Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Packaging Evidence o 10 The paper bindle is ideal packaging for small, dry, trace evidence. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Mapping the Outdoor Crime Scene (continued) o 17 Measuring and Marking Evidence Positions Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Analyze the Evidence o 18 Forensic lab technicians are specialized to process only one type of evidence. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Crime-Scene Reconstruction o Crime scene reconstruction involves: • • o 19 Forming a hypothesis of the sequence of events from before the crime was committed through its commission Comparing the evidence to witnesses statements Investigators need to maintain an open mind as they examine all possibilities. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Staged Crime Scenes o Commonly staged types of crime scenes include: • • • 20 Arson Murder staged to look like a suicide Burglary Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Summary o o o 21 Locard’s Principle of Exchange states that contacts between people and objects during a crime can result in a transfer of material. Evidence may be direct, as in eyewitness accounts, or circumstantial, which does not directly support a fact. Evidence may be physical or biological. Trace evidence is a small amount of physical or biological evidence. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Summary (continued) o o o 22 A crime-scene investigation team consists of police officers, detectives, crime-scene investigators, medical examiners, and specialists. A crime-scene investigation consists of recognizing, documenting, photographing, and collecting evidence from the crime scene. First-responding officers must identify the extent of a crime scene, including primary and secondary scenes when possible, secure the scene(s), and segregate witnesses. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016

Summary (continued) o o 23 After examining the crime scene(s) and identifying evidence, the crime-scene investigators document the scene(s) with photographs and sketches. Crime scene(s) are sometimes precisely mapped to ensure that no evidence is overlooked. Evidence must be properly handled, collected, and labeled so that the chain of custody is maintained. Evidence is analyzed in a forensic laboratory, and the results are provided to detectives, who develop a possible crime-scene scenario. Forensic Science: Fundamentals & Investigations, 2 e Chapter 2 All rights Reserved Cengage/NGL/South-Western © 2016