Which test requires that expert testimony be based on accepted scientific principles?

The Frye test is based on the principle that scientific evidence must be sufficiently established and accepted within the relevant scientific community before it can be admissible in court. This means that for expert testimony to be considered credible, it must stem from techniques or theories that have gained general acceptance among experts in the field. Thus, the Frye test emphasizes the consensus within the scientific community about the validity of the methods used by the expert.

In contrast, the Daubert guidelines, while also addressing the admissibility of expert testimony, focus more on the reliability and relevance of the scientific evidence rather than just general acceptance among peers. Chain of custody pertains to the handling and preservation of evidence rather than the qualifications of expert testimony, while Rule 702 of the Federal Rules of Evidence allows for expert testimony based on specialized knowledge that will assist the trier of fact, but does not specifically require adherence to established scientific principles like the Frye test does.