Which type of prints are contamination by blood and are found on weapons or scene items?

• A. Contaminated prints
• B. Latent prints
• C. Plastic prints
• D. Patent prints

Answer: (A)

When a fingerprint surface is touched by a person who has blood on their finger, the blood becomes part of the print. That contamination makes the print directly visible and recoverable on weapons or scene items, rather than remaining hidden or requiring special development. This is why it’s described as a contaminated print—the contaminant (blood) alters the print and allows immediate identification and collection, sometimes even yielding DNA from the blood itself.

Latent prints are invisible until developed, which isn’t the case here because the blood provides the visibility. Plastic prints are three-dimensional impressions in soft surfaces, and patent prints are visible prints produced by a visible substance like blood or ink; the scenario emphasizes the contamination aspect rather than just visibility, hence the term contaminated prints.