Who acts as the gatekeeper for the admissibility of expert scientific testimony under Daubert?

• A. The jury acts as gatekeeper, deciding admissibility.
• B. The trial judge acts as gatekeeper, but only for lay witnesses.
• C. The appellate court acts as gatekeeper during trial.
• D. The trial judge acts as gatekeeper, applying Daubert to determine admissibility of expert scientific testimony.

Answer: (D)

Daubert assigns the trial judge the gatekeeper role for expert scientific testimony, ensuring that the methods and principles underlying the testimony are reliable and relevant before it can reach the jury. The judge uses Daubert’s framework to assess admissibility, looking at factors like whether the theory or technique can be tested, has been subjected to peer review, has known error rates, relies on standards, and enjoys general acceptance, while also allowing other trustworthy considerations relevant to reliability. This gatekeeping is about the admissibility of expert testimony, not about whether the jury should weigh or credit it once admitted. Lay witnesses are governed by different rules, and appellate courts don’t perform this gatekeeping during trial—they review admissibility decisions after the fact. So the best description is that the trial judge acts as gatekeeper, applying Daubert to determine admissibility of expert scientific testimony.