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Law 101: Legal Guide for the Forensic Expert

Facts of the Case

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National Institute of Justice (NIJ) (see reuse policy).

An expert should obtain all of the facts about the case to be able to render an informed opinion.

If an expert knows certain facts about the case before scientific testing is conducted, the expert should not allow such knowledge to influence the comprehensiveness of results reported (i.e., making results fit facts known ahead of time vs. reporting a variety of potential conclusions that all fit the data).

An expert should remain objective and neutral when examining and reporting the evidence, during engagement and throughout the trial process. Despite being engaged by one party, it is imperative that the expert witness remembers that the role is not that of an advocate for either party.

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