As A Criminalist, You Have Been Asked To Speak To A Group

As A Criminalist You Have Been Asked To Speak To a Group of Students

As a criminalist, you have been asked to speak to a group of students who want to learn more about crime scene investigation. Write a 1,050- to 2,100-word paper in which you address the following in the same manner as you would address the group of students: Identify the procedures associated with crime scene evaluation. Describe the preservation and collection of physical evidence. Describe the procedures for securing and searching the crime scene to include crime scene safety. Identify methods of recording the crime scene.

Paper For Above instruction

Understanding the intricacies of crime scene investigation is essential for aspiring criminalists and law enforcement professionals. Crime scene investigation entails a systematic approach to evaluating a scene, securing evidence, and ensuring accurate documentation, all while maintaining safety protocols. When addressing students, it is vital to break down each component into clear, comprehensible steps to foster a comprehensive understanding of this critical forensic process.

Procedures Associated with Crime Scene Evaluation

The initial step in crime scene investigation involves a thorough evaluation of the scene. Upon arrival, investigators must first establish the scene's boundaries and determine its scope. This process includes conducting a preliminary walk-through to identify potential evidence, assess the scene's condition, and develop an initial plan for investigation (Saferstein, 2018). During this walk-through, investigators note significant features, unusual activities, and any potential hazards. An essential aspect is establishing the scene's chronological and physical boundaries to prevent contamination or loss of evidence.

Documentation begins during this walk-through with detailed notes, photographs, and sketches. Investigators assess lighting conditions, weather influences, and potential evidence contamination sources. Additionally, they identify individuals present at the scene, establish access points, and control entry to prevent evidence compromise. These procedures lay the foundation for meticulous evidence collection and subsequent analysis.

Preservation and Collection of Physical Evidence

Once the scene is evaluated, the preservation and collection of evidence take precedence. Proper evidence preservation is critical to maintaining the integrity of physical evidence to ensure accurate forensic analysis later. The process starts with assigning clear labels and packaging to prevent cross-contamination. For biological samples, sterile containers or swabs are used, while larger items are secured in suitable materials to prevent damage.

Investigators follow strict protocols based on the type of evidence. For instance, trace evidence like fibers and hairs is collected carefully with tweezers and stored in paper bindles, which prevent mold and deterioration, as opposed to plastic containers that could promote mold growth (Kobilinsky, 2018). Fingerprints are lifted using powders or superglue vapors and then documented through photographs. Firearms and bullets are carefully collected in rigid containers to prevent accidental discharge or damage. Preserving evidence also involves controlling the scene to prevent environmental factors such as moisture, heat, or contamination from degrading the evidence.

Chain of custody documentation is vital during collection, recording each person's handling of evidence from the scene to the laboratory. This documentation ensures the evidence's integrity is maintained throughout the investigation process.

Procedures for Securing and Searching the Crime Scene, Including Safety

Securing the crime scene involves establishing physical boundaries with barriers such as crime scene tape, guards, or natural borders to restrict access only to authorized personnel. This step helps prevent tampering, contamination, or loss of evidence (James & Nordby, 2017). Once secured, a detailed record of all individuals entering and leaving the scene is maintained as part of the chain of custody.

Safety is paramount during scene security and search procedures. Investigators must wear personal protective equipment (PPE) such as gloves, masks, shoe covers, and eye protection to prevent contamination and protect themselves from potential hazards like biohazards or toxic substances. Conducting a risk assessment before beginning searches ensures that safety protocols are followed to minimize accidents or exposure to hazardous materials.

Searching the scene involves systematic methods to ensure comprehensive evidence recovery. The most commonly used techniques include grid, spiral, strip/line, and zone searches. The choice of method depends on the scene's size and complexity. Investigators coordinate their efforts to methodically search every area, avoiding missed evidence or duplication of effort. For example, in a large outdoor scene, a strip search allows investigators to cover the area efficiently by dividing it into zones. These procedures are crucial for ensuring no evidence is overlooked and that the scene's integrity is maintained.

Methods of Recording the Crime Scene

Reliable recording methods are essential for documenting the crime scene accurately. Photographs provide visual records of the scene, capturing the initial condition, evidence placement, and scene context. Overhead and detailed close-up photographs should be taken from multiple angles, with scales included to assess size (Hageman, 1994). Video recordings can offer dynamic views of the scene, aiding in later analysis and courtroom presentation.

Sketching the scene involves creating detailed drawings, often with measurements, to depict evidence locations and scene layout. Sketches can be rough or finished, and they should include a legend, compass rose, and scale for accuracy. Investigators often prepare preliminary sketches during the walk-through, followed by more detailed finalized diagrams after evidence collection.

Notes and reports are also vital components of documentation. Investigators record step-by-step procedures, observations, evidence collected, and persons present at the scene. Proper documentation ensures transparency, reproducibility, and legal admissibility of the investigation findings.

Conclusion

Effective crime scene investigation relies heavily on structured procedures for evaluation, evidence preservation, scene securing, searching, and documentation. Each step plays a critical role in ensuring the integrity of the evidence and the overall investigation's success. As future criminalists and law enforcement specialists, understanding and implementing these procedures ensures justice for victims, improves investigation efficiency, and upholds the integrity of forensic science.

References

• Hageman, J. (1994). Crime scene photography. Law Enforcement Technology, 21(4), 28-31.
• James, S. H., & Nordby, J. J. (2017). Forensic science: An introduction to scientific and investigative techniques (4th ed.). CRC Press.
• Kobilinsky, L. (2018). Forensic science: Advances and perspectives. CRC Press.
• Saferstein, R. (2018). Criminalistics: An introduction to forensic science (12th ed.). Pearson.
• National Institute of Justice. (2020). Crime scene investigation: A guide for law enforcement. NIJ.gov.
• Thompson, W. C. (2015). Crime scene investigation: A guide for law enforcement. CRC Press.
• Lee, H. C., & Miller, R. K. (2020). Basic criminal investigation. CRC Press.
• Stoney, D. (2017). Crime scene processing and evidence collection. Journal of Forensic Sciences, 62(3), 736-743.
• Fisher, B. A., & Fisher, D. B. (2016). Techniques of crime scene investigation. CRC Press.
• Pollock, J. M. (2018). Forensic science reform. Academic Press.