Latent Impression
Definition
An impression that is invisible or barely visible until developed or lifted. Dust impressions on dark floors and oblique-light-only impressions sit here.
- Evidence type
- Footwear, tyre, footprint impressions
- Visibility
- Invisible or barely visible without aid
- Example
- Dust impressions on dark flooring
- Detection aid
- Oblique lighting
Common questions
How is a latent impression typically documented at a scene?+
Oblique lighting is used to cast shadow across the fine surface irregularities the impression leaves, and electrostatic dust lifting or gelatin lifters can transfer the impression to a contrasting surface for photography and comparison.
What distinguishes a latent impression from a plastic impression?+
A latent impression is a thin surface deposit, such as dust displacement, that leaves no three-dimensional depth, while a plastic impression is a moulded indentation left in a soft material like mud or snow, which is documented and cast differently.
Related terms
- 2D Impression
- A two-dimensional print on a hard, flat surface (tiled floor, polished cement, paper). Lifted with electrostatic dust lifter (ESLA), gel lifter, or...
- 3D Impression
- An impression made in a deformable medium: soil, sand, snow, mud, soft asphalt. The sole or tread pushes into the medium and...
- Class Characteristic
- A feature shared by an entire group of objects (every shoe of one model has the same sole tread; every tire of...
- Individual Characteristic
- A characteristic unique to a specific typewriter unit arising from manufacturing variation or service wear; used to identify or eliminate a specific...
- Patent Impression
- An impression that is visible to the naked eye without enhancement. A bloody shoeprint on white tile is patent.