The state of South Dakota follows the Daubert test for the admissibility of expert witness testimony. State v. Lemler, 774 N.W.2d 272 (S.D. 2009). The purpose of this test is to ensure that expert testimony is reliable before it is admitted. Id. Under this test, courts should analyze: “(1) whether the theory or technique in question can be (and has been) tested, (2) whether it has been subjected to peer review and publication, (3) its known or potential error rate and the existence and maintenance of standards controlling its operation, and (4) whether it has attracted widespread acceptance within a relevant scientific community.” Id. This test is flexible, and courts should consider the factors and even if not all are met, if the court feels the evidence is relevant and reliable, the testimony will be admissible. Id. Additionally, the court should focus on the “principles and methodology” used by the expert and not on the conclusions the expert testifies to. Id.
