What is the difference between a latent print and an impression?

What is the difference between a latent print and an impression?

• A. A latent print is invisible and requires development; an impression is a visible mark left by a finger.
• B. A latent print is visible; an impression is invisible.
• C. A latent print is formed by DNA; an impression is formed by mud.
• D. A latent print is always on metal; an impression is on glass.

Answer: (A)

The main idea is the difference in visibility and how they’re created at a scene. A latent print is invisible to the naked eye because it’s made from naturally deposited skin secretions—oils and sweat—on a surface. It only becomes visible after development techniques such as powders, chemical reagents, or special lighting are used. An impression, by contrast, is a physical mark left by the finger that is already visible or becomes a clear imprint in a soft or malleable surface (like mud, wax, dust, or clay). So, the key distinction is that latent prints are invisible until processed, while an impression is a visible fingerprint imprint produced by contact with a substrate. The other ideas misstate what creates the print or its visibility and are not accurate descriptions of how latent prints and impressions differ.

The main idea is the difference in visibility and how they’re created at a scene. A latent print is invisible to the naked eye because it’s made from naturally deposited skin secretions—oils and sweat—on a surface. It only becomes visible after development techniques such as powders, chemical reagents, or special lighting are used. An impression, by contrast, is a physical mark left by the finger that is already visible or becomes a clear imprint in a soft or malleable surface (like mud, wax, dust, or clay). So, the key distinction is that latent prints are invisible until processed, while an impression is a visible fingerprint imprint produced by contact with a substrate. The other ideas misstate what creates the print or its visibility and are not accurate descriptions of how latent prints and impressions differ.