The Reliability of Fingerprint Identification - A Case Report

Crime Scene Processing
"Latent" prints are chance or unintentional prints found on items of evidence or at a crime scene. Some prints can be plainly seen. They are made by a finger coated with a foreign substance like blood, grease, or dirt. Some prints are "plastic impressions" imprinted in pliable substances like butter, candles, putty, and semidry paint. Other prints, invisible or barely visible to the eye, are ...

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Fingerprint Evidence Collection
Latent Print evidence can typically be divided into two categories: Porous and Non-porous. Porous evidence such as paper, unfinished wood, cardboard, etc., is normally conducive to the preservation of prints because latent print residue can soak into the surface. Non-porous evidence such as plastic, glass, metal, foil, etc., is much more fragile because the latent print residue may just be lying on the surface. Even the slightest  handling can "wipe away" a latent print on non-porous surfaces...

How You Often Destroy Prints at Crime Scenes
DO wear gloves... but maybe not for the reasons you think!  Wear gloves primarily to keep your hands clean.  Assume that any relatively smooth area your gloves touch will destroy identifiable latent prints on non-porous or semi-porous surfaces.  When you are handling evidence...

Super Glue Fuming
By NOT superglue fuming nonporous evidence before you mail it to the lab, you help the bad guys..... it's about the same as wiping the evidence clean. Do NOT expect latent finger or palm prints on a pistol, knife, can, bottle, or credit card to survive mailing to the lab if you don't either...
 

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