2/9 FSCI

Crime Scene Investigation Essentials

Initial Assessment

  • Purpose of Initial Survey

    • Determine immediate situation before moving anything.
    • Check for a person's pulse; if they are not alive, further actions change.

  • Indicators of Death

    • Rigor Mortis: Body rigidity indicating death; often sets in several hours after death.
    • Lividity: Pooling of blood at the lowest points of the body, indicating time since death.

  • Situational Awareness

    • Presence of blood: Observe coagulation to assess viability of resuscitation attempts.
    • Importance of leaving everything undisturbed to preserve crime scene.

Crime Scene Preservation

  • Photo Documentation

    • Photograph the scene extensively before altering anything.
    • Measurements should be taken to document the scene layout and potential evidence.

  • Issues to Consider During Investigation

    • The five critical questions:
    • Who?: Identify individuals involved.
    • What went wrong?: Determine circumstances leading to the incident.
    • Where?: Identify locations of entrance and exit.
    • Why?: Examine motives behind the event.
    • How?: Assess methods used in the event.

Evidence Preservation Techniques

  • Fragile Evidence

    • Footprints in Various Conditions:
    • Cover footprints with a cardboard box if it’s snowing or raining to prevent deterioration.
    • Castings can be taken in mud, wet concrete, or snow; spray to preserve details.

  • Hair and Fibers

    • Employ methods to preserve hair strands using tweezers or controlled environments to prevent loss.
    • Collect all hair samples for microscopic analysis in order to determine their origin (human vs. animal).

Investigator Responsibilities

  • Documentation and Reporting

    • Maintain ongoing notes throughout the crime scene investigation.
    • Create sketches and catalog photographs.
    • Collect evidence properly and prepare detailed reports.

  • Collaboration

    • A crime scene investigator may work alone but can also delegate responsibilities within a team.

Evidence Collection Guidelines

  • Hair Sample Collection

    • Collect both human and animal hair samples; differences are determined post-collection via microscopy.
    • Maintain comprehensive records of all evidence collected, adhering to chain of custody practices.

  • Importance of Organized Notes

    • Uniformity in documentation is vital. Notes should be kept in professional notepads or formatted consistently.
    • All notes should clearly delineate dates, times, incidents, and observations made at the scene.

Scene Control and Security

  • Establishing Command

    • Identify an individual in charge to oversee the investigation's process and organize resources.

  • Important Initial Observations

    • Pay attention to odors; they can indicate toxic or volatile substances.
    • Record conditions or disturbances indicative of a struggle (e.g., furniture disarray).

  • Physical Evidence Recording

    • Look for indications of forced entry (e.g., door conditions, window integrity).
    • Capture evidence of drugs or consumption (e.g., bottles, ashtrays), which may provide insight into the situation.

Photography and Evidence Assessment

  • Photographing Evidence

    • Capture the layout and context of the crime scene as is, including the state of light switches and their conditions.
    • Unaltered crime scenes will yield the best evidence.

  • Conditions to Note

    • Conditions related to blood spatter patterns help to understand events leading to injury or death.
    • Determine the presence and positioning of items (e.g., light switches, furniture).

Systematic Evidence Search

  • Methodology
    • Ensure a thorough and methodical approach to prevent missed evidence.
    • Take time to document everything meticulously to avoid gaps in testimony or evidence collection.

Conclusion

  • The importance of a systematic approach to a crime scene is paramount; careful planning, documentation, and collaboration fosters accurate investigations. Further discussions on the topic of crime scene photography and advanced evidence collection techniques will continue in future sessions.