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Law 101: Legal Guide for the Forensic Expert

Evidence Retesting

In cases where biological evidence was collected, still exists and was initially subjected to DNA testing, exclusionary results could support a claim of innocence.

However, reasonable individuals might not agree that the results raise a reasonable doubt about guilt. This includes cases where there is disagreement for policy and/or economic reasons about whether DNA testing should be permitted at state expense for anyone and/or for indigents.

These cases may raise difficult policy issues about how far post-conviction relief should reach. Factors that bear on the decision to test will include:

  • Additional evidence in the case.
  • Whether conviction was based on a guilty plea, a no-contest plea, or a trial.
  • The availability of DNA testing at the time of trial.
  • The availability of appropriate DNA technology at the time of trial.

The preceding factors are moot if no biological evidence was available for testing, or if the existing biological evidence sample size is too small to retest.

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Date Created: August 7, 2023