Porous surfaces are places where a material absorbs latent print. An example of a porous surface is a piece of paper. Some of the chemicals that forensics science developers use to process latent fingerprints in a porous material include physical developer and ninhydrin (Houck, 2016). The chemicals work by reacting with residues in the latent print, such as inorganic salts and amino acids. The latent print becomes visible through the detection of the patterns of the amino acids in print. Furthermore, the reaction of the latent print residue with ninhydrin makes the print to turn into a purple color. Therefore, forensics examiners photograph the latent prints and try to match the prints with possible suspects. Also, forensics examiners use DFO, a chemical, to detect latent prints on porous materials. The chemical makes the fingerprints absorb light. A forensics examiner also illuminates the prints with blue-green light to get the exact match of the prints. Forensic professionals can locate the item in a crime scene at any particular location. The paper can be on a piece of a desk, on the floor or a chair (Tilstone, Savage & Clark, 2006).
The use of ninhydrin chemical in detecting latent prints is common among forensic scientists because it is cheap, productive and efficient (Tilstone, Savage & Clark, 2006). The use of ninhydrin produces permanent documents because crime scene experts photograph the prints. The experts print the prints on paper and keep a soft copy of the pictures, where they are stored in computer systems. The use of computer systems to store soft copies of latent prints makes it easy to cross-match the prints with police records. According to Houck (2016), ninhydrin has helped crime scene experts to detect criminals.
Houck, M. M. (2016). Forensic fingerprints. San Diego, CA : Academic Press
Tilstone, W. J., Savage, K. A., & Clark, L. A. (2006). Forensic science: An encyclopedia of history, methods, and techniques. Santa Barbara, Calif: ABC-CLIO.