Establishing a Chain of Custody and Preserving Evidence for Testing
The original condition of the evidence and its packaging should be photographed and carefully documented at the time of its discovery and throughout all stages of the postconviction procedures.
The defense attorneys and prosecutors should develop mutually agreeable methods for preserving the chain of custody for the evidence throughout the testing process. This should include photographing the evidence and its packaging when it is received and sent; an evidence labeling system that includes initialing by evidence handlers with times and dates; and, if possible, photomicrographs of relevant slides, especially slides containing sperm in sexual assault cases.
The evidence should be properly preserved. The most important factor in storing evidence is a dry atmosphere at room temperature.
It is important to continue to carefully preserve the evidence even after postconviction DNA testing has been conducted because future developments in the technology may make it possible to obtain additional results at a later date. For example, there have been several cases where RFLP DNA testing was conducted and the results were inconclusive, but PCR-based testing was conducted years later and conclusive results were obtained. Particularly with the advent of mitochondrial DNA testing, there will be many new cases where future DNA testing will be able to produce results that were not previously obtainable.
Go to the Next Section: Procedure After Postconviction Testing Results Have Been Obtained
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