What techniques are CSAs trained in for processing latent prints?

Crime Scene Analysts (CSAs) are trained in both powder and chemical methods for processing latent prints because each has unique advantages and is suitable for different surfaces and conditions.

Powder methods involve using fine powders that adhere to the moisture and oils present in latent prints. These powders are typically applied with brushes or puffs to reveal the print on various non-porous surfaces like glass and plastic. The simplicity and effectiveness of powder methods make them a fundamental technique for detecting and preserving prints.

Chemical methods, on the other hand, involve using chemical reagents that react with components of the latent print. These methods are particularly useful for porous surfaces like paper, where traditional powder techniques would be less effective. Chemicals like ninhydrin and superglue (cyanoacrylate) fuming can enhance the visibility of prints that might otherwise be undetectable.

The combination of both techniques allows CSAs to effectively process a wider range of surfaces and conditions encountered in crime scenes, maximizing the chances of recovering usable latent prints. This multifaceted approach is a critical part of a CSA's training, ensuring versatility and thoroughness in evidence collection.