Question

Latent fingerprints were noted on the following five items. For each item which visualization method you would use. I realize that you can use a combination of methods, but from the combination, select the most important one. In addition, state whether this method is physical, chemical or optical. Refer to class notes. Lastly, explain why you would use it. DA pop can left at the crime scene by the suspect. A painting that was stolen from the gallery. i) A glass window that was broken in order to gain entry.

please explain them clearly.

Answer 1

i) A pop can left at the crime scene by the suspect. - Dusting the surface with a finger print powder which is black granular, aluminum flake, black magnetic, etc. such that the fingerprints become visible and can be photographed and lifted from the surface of the can using an adhesive tape.This can further be preserved by placing on a latent lift card.

ii) A painting that was stolen from the gallery - Chemical developers may be used for porous surfaces since some chemicals react with certain latent print residue for example amino acids and inorganic salts. Examples of chemicals that may be used are: DFO (1,2-diazafluoren-9-one), Ninhydrin .

iii) A glass window that was broken in order to gain entry. - Alternate Light Source method using laser or LED devices that emit a particular wavelength of light. Or Cyanoacrylate, also called as superglue fuming method. These methods are used instead of dusting finger-print powder because the latter can contaminate the evidence.