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.
The following processes have proven to be reliable for the development of fingerprints:
- Ninhydrin
- Visualization/lifting in blood
- Chemical lifting
- Fume circulation
Address the following in 2 FULL PAGES using the bullet below and using the Four fingerprinting developments listed above.
- Explain the following for each fingerprinting method selected:
- Once the surface/material/substance has been designated for fingerprinting, what is the process of each selected method listed above? Describe and explain in detail using a step-by-step process.
- Briefly explain the purpose of each step.