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Overview
Laboratory Time and Resources
Interacting With Crime Laboratories
DNA Evidence: Probative Value and Prioritization
Communicating With the Prosecutor
Outsourcing Considerations
Leveraging Limited Resources
Avoiding Steep Costs
Communicating With the Legislature
Evidence Retention Policies
Best Practices for Handling “Cold Hits”
Offender Collection Statutes
Partial Matches
Familial Searching
Rapid DNA Technology
Resources, Guides and Best Practices

Laboratory Time and Resources

Time Required to Perform Laboratory Analysis

Step 2: Body Fluid Stain/Tissue Identification

The extent of this step varies from laboratory to laboratory. Some laboratories perform only preliminary tests, which are frequently less time-consuming, but are not definitive. In addition to preliminary testing, laboratories may perform confirmatory testing on stains that have a positive preliminary test result. Confirmatory tests are highly discriminating and allow the analyst to report the origin of the fluid/tissue with a high degree of scientific certainty. These tests typically require significantly more time to perform.

composite image. image one: blue alternate light source showing possible location of biological fluid on item of clothing evidence. image two: purple stain of acid phosphotase presumptive color test for semen. image three: computer screen displaying confirmatory microscopic evaluation for sperm cells.

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