Latent Fingerprint
Definition
A fingerprint impression deposited by the transfer of sweat and oil from fingertip ridges that is not immediately visible to the naked eye and requires development (powdering, chemical treatment, or optical imaging) to be recorded.
- Deposited by
- Sweat and oil transfer from ridge detail
- Visibility
- Not visible to the naked eye
- Development methods
- Powdering, chemical treatment, optical imaging
- Contrast with
- Patent (visible) and plastic (moulded) impressions
Common questions
Why does substrate choice determine which development method is used on a latent print?+
Porous surfaces like paper favour chemical reagents such as ninhydrin that react with amino acids, while non-porous surfaces like glass or metal favour powder dusting or cyanoacrylate fuming, since each method targets residue components that behave differently by surface type.
How does a latent print differ from a patent print in handling?+
A patent print is already visible, such as one left in blood or ink, and only needs photography before collection, whereas a latent print must first be developed to reveal ridge detail before it can be photographed or lifted.
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