- Frye's "general acceptance" test (1923) was superseded by the adoption of the Federal Rules of Evidence (1975).
Nothing in the rules as a whole or in the drafting history of rule 702 gives any indication that "general acceptance" is a necessary precondition to the admissibility of scientific evidence. Moreover, such a rigid standard would be at odds with the rules' liberal thrust and their general approach to relaxing the barriers to "opinion" testimony.
- The Judge must ensure that:
The expert's testimony is relevant and "rests on" a reliable foundation.
Relevancy standard = FRE 702 = assist trier of fact
Reliability standard = FRE 702 = scientific knowledge
..."scientific" implies a grounding in science's methods and procedures, while ... "knowledge" connotes a body of known facts or ideas inferred from such facts or accepted as true on good grounds.
- Pursuant to FRE 104(a):
The judge must make a preliminary assessment of whether the testimony's underlying reasoning or methodology is scientifically valid and properly can be applied to the facts at issue. Many considerations will bear on the inquiry, including:
- Whether the theory or technique in question can be (and has been) tested,
- Whether it has been subjected to peer review and publication,
- Its known or potential error rate,
- The existence and maintenance of standards controlling its operation, (e.g., SOPS, QC/QA, CLIA, third-party payers)
- Whether there is widespread acceptance within a relevant scientific community.
- Whether the inquiry is a flexible one, and its focus must be solely on principles and methodology, not on the conclusions that they generate.
- Cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof ... Is the appropriate means by which evidence based on valid principles may be challenged.