When a sexual assault occurs, police encourage the victim to complete a “rape kit” – a standardized procedure to collect evidence needed to find and prosecute the assailant. But instead of rapid usage of this evidence, tens of thousands of the completed kits still sit in police warehouses – untested and waiting.

Dr. Kelly Walsh, forensic scientist at the Urban Institute, helps us understand what's behind the huge failure and what we need to do about it.

Find more at criminalinjusticepodcast.com.