Untitled Flashcards Set

Crime Scene Investigation

Introduction

• Crime scenes transform ordinary household items into evidence.

• Importance of a properly processed crime scene, which serves as the foundation for forensic analyses.

• The disparity between media portrayals of crime scenes and the complex realities of processing them.

• The necessity of trained personnel for crime scene processing.

Of Artifacts and Evidence

• Crime scene processing is a form of "careful destruction" of the scene.

• Evidence is information used in legal investigations to establish facts.

• Comparison between archaeological excavation and crime scene processing; both are one-way processes.

Key terms:

Þ   Datum: A fixed reference point for measurements.

Þ   Artifact: A human-made object.

Þ   Feature: A non-portable artifact.

Þ   Provenance: Origin of an item in 3D space.

Crime Scene Investigation

• Unique nature of each crime scene due to various factors such as weapon, location, and individuals involved.

• Importance of following protocols while remaining flexible in response to scene conditions.

First on the Scene

Duties of the First Officer (FO)

1. Detain potential suspects.

2. Provide medical aid to those in need.

3. Secure the scene against destruction or alteration of evidence.

4. Control access to the scene.

• Assess the scene's security and document all entries and exits.

Plan of Action

• Preparation includes obtaining search warrants and defining scene borders.

• Command station setup for effective communication away from the scene.

• Assign roles and responsibilities to personnel for an organized investigation.

Preliminary Survey

• Perform a careful walk-through of the crime scene.

• Take preliminary photographs and extensive notes to document conditions and initial findings.

Photography

• Start photographing as soon as possible in an overall to close-up manner.

• Use scales for contextual reference in images and document photography in a log.

Sketch

• Create sketches that complement photography, including distances and locations of evidence.

• Must include essential details such as case identifier, dimensions, and weather conditions.

Chain of Custody

• Vital documentation of evidence movement from collection to court presentation.

• Inaccuracies in the chain can compromise the evidence's reliability.

Crime Scene Search and Evidence Collection

• Evidence collection should follow a methodical pattern (spiral, grid, etc.).

• Measurements of evidence locations should be precise and systematically documented.

Final Survey

• Conduct a recap of the entire investigation to ensure thoroughness.

• Document the release of the crime scene, including timings and persons involved.

Submission of Evidence to the Laboratory

• Evidence must be submitted with appropriate documentation detailing its origin and required examinations.

Safety

Risks Involved

• Crime scenes may present chemical and biological hazards, including exposure to bloodborne pathogens.

Sources and Forms of Dangerous Materials

• Inhalation: Airborne contaminants pose serious health risks.

• Skin Contact: Common route for contaminants; protective attire is essential.

• Ingestion: Less common but hazardous when corrosive materials are involved.

• Injection: Sharp objects can pose severe risks during evidence collection.

Universal Precautions

• Treat all human blood and fluids as potentially infectious.

• Use personal protective equipment (PPE) properly to minimize exposure risks.

Personal Protective Equipment (PPE)

• Select appropriate gloves based on the materials handled; keep in mind personal allergies.

• Use eye protection when dealing with hazardous materials.

• Ensure foot and other protections are adequate based on the scene's risks.