What type of developer do patrol officers typically use for latent prints?

What type of developer do patrol officers typically use for latent prints?

• A. Black powder
• B. UV dye
• C. Magnetic powder
• D. Fluorescent powder

Answer: (A)

The main idea here is understanding what field officers commonly use to visualize latent fingerprints on-scene. For patrol work, the go-to method is dusting the suspected surface with powder to reveal the print. Black powder is the standard choice because it is inexpensive, portable, easy to use, and works well on many nonporous surfaces like glass, metal, and painted items found at a scene. It provides clear ridge details and can be lifted with tape for processing. Magnetic powder is also used in the field, especially on delicate or textured surfaces where brushing might cause damage, but it isn’t the typical first option because it can be less reliable for some surfaces and requires a magnetized applicator. UV dye and fluorescent powders serve specialized visualization under UV light and are less commonly used as the routine field method compared to black powder.

The main idea here is understanding what field officers commonly use to visualize latent fingerprints on-scene. For patrol work, the go-to method is dusting the suspected surface with powder to reveal the print. Black powder is the standard choice because it is inexpensive, portable, easy to use, and works well on many nonporous surfaces like glass, metal, and painted items found at a scene. It provides clear ridge details and can be lifted with tape for processing.

Magnetic powder is also used in the field, especially on delicate or textured surfaces where brushing might cause damage, but it isn’t the typical first option because it can be less reliable for some surfaces and requires a magnetized applicator. UV dye and fluorescent powders serve specialized visualization under UV light and are less commonly used as the routine field method compared to black powder.