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Term of the Month

Defining Criminal Justice Research

Welcome to NIJ’s Term of the Month. Each month we are featuring a term from our scientific research portfolios informing significant American justice system issues and solutions. Along with a definition, we are providing links to related resources that illuminate the featured term.

August 2021 — Alternate Light Source

In forensic science, an alternate light source uses monochromatic light to detect and identify physical evidence, including bruises, body fluids, hair, clothing fibers, and other trace materials. This technology takes advantage of a material’s inherent luminescent properties that cause it to glow when struck with a specific wavelength of light.  

Related NIJ content:  

Detection of Inflicted Bruises by Alternate Light: Results of a Randomized Controlled Trial

Just Science: 2019 NIJ R&D: Just Skin Deep (Podcast)


Date Created: January 28, 2021