Fingerprint evidence is one of the most common and important pieces of crime scene evidence. One of the most important steps in the examination of fingerprint evidence is locating the prints at the crime scene and accurately processing them. Fingerprints are usually visualized and lifted using fine particles or powders (also known as a physical method), such as powder dusting, luminescent powders, and magnetic powders. There is also a process referred to as chemical lifting, including such techniques as iodine fuming, spray reagents, and cyanoacrylate fuming.
A senior investigator has instructed one of the new recruits to lift possible fingerprints from various spots within the crime scene and to collect and preserve footwear and tire track impressions that have been located outside of the abandoned warehouse. This is the first time that the investigator will be performing these duties in an actual crime scene, and he has asked you to help him through the process to ensure that he produces the best evidence. In this assignment, you will provide a walk-through for the new investigator on the fingerprinting and casting processes.
What general areas should always be inspected for possible fingerprints? Explain.
What is the documentation process regarding the lifting of fingerprints? Explain in detail.
What are the 2 general types of surfaces in which investigators must lift fingerprints? Explain.
What is the casting process used for the footwear and tire tread impressions outside of the warehouse? Explain in detail.
What materials will you use to lift these molds from the ground? Explain.
What is the process for casting these impressions and creating molds? Describe and explain in detail using a step-by-step process.
Briefly explain the purpose of each step.
Explain the following for each fingerprinting method listed: Cyanoacrylate fuming, Ninhydrin, Visualization/lifting in blood, and Visualization/lifting on human skin.
Once the surface/material/substance has been designated for fingerprinting, what is the process for the selected method? Describe and explain in detail using a step-by-step process.
Briefly explain the purpose of each step.
Be sure to reference all sources using APA style.
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The areas that should be inspected for possible fingerprints are areas not normally touched or on surfaces capable of yielding viable fingerprints. Also the areas that are directly related to the crime should be inspected. For example, in case of a murder the areas close to the body, the articles capable of yielding fingerprints on the body, or the murder weapon should be inspected for possible fingerprints. The explanation is that the point of entry, the location of the crime, areas where the suspect may have cleaned up, and the point of exit must be examined for fingerprints.
The documentation process for lifting of fingerprints must contain the basic data. It must have the crime scene address, the name of the victim, the date and time of your arrival and departure from the scene, and your name. Documentation must indicate where items of evidence from which fingerprints were taken were located at the scene and the condition of the evidence before collection (a). For example if the victim was killed with a gun, the documentation must be documented in its original location, orientation, and condition. It is necessary to document the surface before processing. Next the latent prints must be designated and labeled on the surface. This means documenting the manner in which the surface was touched, the distortion in the print and anatomical source of the latent print. Next the patent prints must be described. The location and orientation of the prints must be documented accurately. Examination quality photographs must be taken and development techniques must be applied.
The two general types of surfaces in which investigators must lift fingerprints are porous surfaces and non porous surfaces. Nonporous surfaces include metal, glass, or plastic. Porous surfaces are paper, cloth, or wood. There are other classifications of surfaces in ...
This solution explains the fingerprinting process and techniques. The sources used are also included in the solution.
Types of Evidence at a Crime Scene Investigation
There are numerous examples of physical and trace evidence, and although general crime scene procedures will be the same, the type of evidence will determine the specific collection procedure. Below is a list of many types of evidence that may be found at a crime scene.
- Petroleum products
- Powder residues
- Serial numbers
- Soils and minerals
- Tool marks
- Vehicles and lights
- Woods and vegetative materials
Address the following:
- Select 5 - 7 of the above types of physical evidence, and explain processes involved with the identification, collection, and preservation of each type.
- Answer the following questions for each of your selections: ◦How is it identified? Explain. What class characteristics might you find associated with the selected type of evidence?
- How difficult is the type of evidence to identify? Explain.
- What is the process for removing and collecting the evidence? Explain in detail. Your analysis must reference specific tests, histological staining, microscopes, and other equipment or techniques that should be used.
- What tools are necessary to collect the evidence? Describe.
- What challenges exist regarding the collection of the evidence? Explain.
- How is the evidence stored and preserved? Explain. How difficult is it to store and preserve the evidence? Explain.
- How might the evidence become contaminated and therefore inadmissible in court? Explain.
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