Care should be taken in selecting a single sample (or at least the minimum number of samples) for testing that will give meaningful/useful results for a particular case. There is no point in testing samples in category 5 cases. (See Determining Which Samples to Test). Criteria for selection of the sample may include:
The availability of and necessity for samples from known individuals who should be tested for exclusionary purposes will need to be carefully considered. For example, in sexual assault cases where the defendant is excluded as a donor of the DNA, it is imperative that a sample from the victim and any known consensual partner(s) be tested in order for that exclusionary result to provide exculpatory evidence. Additionally, testing of the victim's sample in sexual assault cases can serve as a built-in control to confirm that the testing has been performed correctly and that the questioned sample is, in fact, linked to that victim.
Go to the Next Section: Retention of Samples for Future Testing
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