FRSC 1011H Lecture Notes - Lecture 5: Arson
7 May 2018
School
Department
Course
Professor
Collection of Crime Scene Evidence
Crime Scene 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
● But if physical evidence is to be used effectively for aiding the investigator, its
presence first must be recognized at the crime scene
● Here, investigators must recognize and properly preserve evidence for lab
examination
Procedures for Collection
● Investigators handle and process physical evidence in a way that prevents
change to the evidence through contamination, breaking, evaporation,
accidental scratching or bending, or other changes occuring as a result of
improper or careless packaging.
Packaging
● Each different item or similar items collected at different locations must be placed
in separate containers.
● Packing evidence separately prevents damage through contact and prevents
cross- contamination
● Evidence from arson scenes should be packaged in airtight metal or glass
containers to prevent the loss of accelerant vapors
● Biological material evidence material should be allowed to air-dry before being
packaged in wrapping paper, manila-envelopes, or paper bags
Chain of Custody
● A list of all person who came into possession of an item of evidence
Obtaining Reference Samples
● Standard / reference sample: physical evidence whose origin is known, such as
blood or hair from a suspect, that can be compared to crime-scene evidence
● Attough most investigators have little difficulty recognizing and collecting relevant
crime-scene evidence, few seem aware of the necessity and importance of
providing the crime lab with a thorough sampling of standard/ reference materials
Document Summary
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. But if physical evidence is to be used effectively for aiding the investigator, its presence first must be recognized at the crime scene. Here, investigators must recognize and properly preserve evidence for lab examination. Investigators handle and process physical evidence in a way that prevents change to the evidence through contamination, breaking, evaporation, accidental scratching or bending, or other changes occuring as a result of improper or careless packaging. Each different item or similar items collected at different locations must be placed in separate containers. Packing evidence separately prevents damage through contact and prevents cross- contamination. Evidence from arson scenes should be packaged in airtight metal or glass containers to prevent the loss of accelerant vapors.
