How to Sketch a Crime Scene

chapter4-crime-scene-sketch-2017.pdf

One of the fundamental skills you will learn in Crime Scene Processing is how to sketch a crime scene. The resources provided here are designed to help you understand the different types of crime scene sketches and how to create rough and final sketches of crime scenes.

How to Use the Nikon D7100

Photography is another key skill for crime scene investigators. In the Crime Scene Processing course, you will use a Nikon D7100 digital single-lens reflex (DSLR) camera with 18-140mm and 35mm lenses and a Nikon SB-700 AF Speedlight. The videos provided here are designed to help you learn how to use this equipment. You can also access a great web tutorial on the Nikon D7000 series on the KenRockwell.com.

How to Collect and Compare Fingerprint Evidence

During the Crime Scene Processing course, you will learn how to collect latent prints from a crime scene. You will also learn how to collect known prints from suspects and victims to use in fingerprint comparisons. The videos below describe some of the common collection methods that you will use in class to collect unknown and known fingerprints.

Taking Legible Fingerprints Guide (FBI).pdf

Collecting Known Prints

Known prints are used to compare to latent fingerprints collected at a crime scene. Known prints are taken from suspects, victims, or other persons that may have had access to a crime scene. Known prints are usually collected on a 10-print card, which includes rolled prints and slap prints. The resources provided here explain how to collect known prints.

Collecting Latent Prints

Latent prints are fingerprints that are invisible to the naked eye. Investigators can use a variety of processors to help visualize the print. Physical processors like black power and magnetic powder can be lifted using physical tape. There are also chemical fingerprint processors, some of which can be collected via tape and others that can be photographed and preserved as digital evidence.

Comparing Fingerprints

This video explains the fingerprint comparison process. Of importance are the reliance on human interpretation, the verification standard for fingerprint "matches" and the evaluative findings for fingerprint examiners.

Analyzing Trace Evidence in Fingerprints

The TED Talk provided here describes how forensic chemists are using fingerprints to identify more than just fingerprint patterns. Using microscopic trace evidence, forensic scientists can detect if the suspect has used drugs, touched explosives, or contacted other substances like condoms.

How to Analyze Bloodstain Patterns

The video provided here shows you to calculate the area of convergence (2D) and area of origin (3D) using bloodstain patterns.

Forensic Science Quality Assurance Guidelines

Scientific Working Groups

A Scientific Working Group (SWGs) consists of scientific experts brought together to identify best practices and develop standard operating procedures and guidelines for the field. There were numerous SWGs developed in the late 1990's, early 2000's, each devoted to a specific area within the forensic science discipline. SWGs were under the regulation of the National Institute of Standards and Technology (NIST), a subdivision of the U.S. Department of Commerce.

The goal of each SWG was to improve evidence recovery, analysis, and testimony relating to the specific type of evidence considered by the SWG. Although many of the original SWGs have been disbanded, most SWGs maintain an online repository of guidelines and other reports that they have published. I encourage you to review the websites below when researching for your Evidence Critique Paper.

American Academy of Forensic Science's Academy Standards Board (ASB)

The Academy Standards Board (ASB) was developed by the American Academy of Forensic Science with the goal of creating a national registry of collection & analysis standards for all forensic science evidence. The ASB is a good source of standard operating procedures and evaluation reports for different forensic science analysis techniques.

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