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Forensic DNA Education for Law Enforcement Decisionmakers


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Many agencies lack formal evidence retention policies, and there is significant variation between jurisdictions that do have policies. Many states have passed or are looking to pass laws requiring indefinite storage of forensic evidence for both unsolved crimes and evidence that was used in criminal convictions.1

The ability of DNA analysis to identify criminals and exonerate the innocent has made this technology an invaluable tool for criminal justice. In some cases, evidence has been destroyed while inmates were appealing their cases. Retaining evidence from criminal convictions allows this powerful technology to be used for cases in which DNA testing was never done or for cases in which older, less sensitive DNA methods were used and inconclusive or indiscriminant results were obtained. Developing policies that provide clear guidelines for the preservation of biological evidence by any agency that is responsible for evidence storage is a major area of need.2 There have been hundreds of exonerations of the innocent after subsequent DNA analysis was performed on remaining evidence in those cases.

1 National Institute of Justice, Postconviction DNA Testing: Recommendations for Handling Requests PDF download: 448kB • Visit the National Criminal Justice Reference System »
2 William P. Kiley, M.S., Focus On Forensics, The Effects of DNA Advances On Police Property Rooms March 2009 »

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