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Vol. 7, Issue 4

Scientific Evidence: Grand Theories and Basic Methods

Curtis E.A. Karnow, Judge of The California Superior Court (County of San Francisco)

21 Aug 2022

California law requires judges to admit expert scientific testimony without resolving scientific controversies, which are left to juries. But case law does not provide a definition of “science” verses inadmissible pseudoscience. And typically juries are asked to resolve ‘scientific’ controversies based on studies never provided to them.

The Essay discusses three common definitions of science, finding them insufficient to address the admissibility of scientific expert opinion. The Essay thus argues against reliance on a definition of ‘science’ and instead recommends the elaboration of criteria for the scientific method including statistical validity, the unreliability of single or preliminary studies, among other criteria for admissibility. In this way, judges, who do have access to the studies, make all significant reliability determinations.

The consequence of this use of scientific methodology as a test for admissibility is an expansion of the “gatekeeper” role of judges in evaluating scientific expert evidence.

To read this Essay, please click here: Scientific Evidence: Grand Theories and Basic Methods.