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Law 101: Legal Guide for the Forensic Expert

Testing Methodology of the Relevant Discipline

  • The technique or theory being offered as evidence must be grounded in testing methodology consistent with the relevant discipline.

  • The scientific testimony offered by the expert must be consistent with methods and procedures of science.

  • The theories behind the scientific knowledge offered in court must be based on the scientific method and properly validated.

The validity of the chosen discipline's methodology and techniques used in the case may be questioned before trial. The judge may hear testimony from experts on both sides and may rule on whether the proposed technique is scientifically valid and reliable or is "junk science" and therefore inadmissible.

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