A Daubert challenge is a hearing conducted before the judge where the validity and admissibility of expert testimony is challenged by opposing counsel. The expert is required to demonstrate that his/her methodology and reasoning are scientifically valid and can be applied to the facts of the case.
The term comes from the 1993 U.S. Supreme Court case, Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), in which the Court articulated a new set of criteria for the admissibility of scientific expert testimony. In its 1999 Kumho Tire v. Carmichael opinion, the Court extended Daubert's general holding to include non-scientific expert testimony as well.
