State v. Dulfu

Expert testimony is scientific when it "possess[es] significantly increase potential to influence the trier of fact as scientific assertions." Scientific evidence must be based on a valid foundation, to be evaluated using the Brown/O'Key factors.

Defendant appealed his conviction of, among other charges,15 counts of second-degree Encouraging Child Sexual Abuse (ESCA II). On appeal Defendant asserted that the trial court erred in excluding expert testimony that there are non-sexual reasons for possessing child pornography. Expert testimony is scientific when the testimony “possess[es] significantly increased potential to influence the trier of fact as scientific assertions.” State v. Marrington, 335 Or. 555, 562, 73 P.3d 911 (2003) (quoting State v. O’Key, 321 Or. 285, 292, 899 P.2d 663 (1995)) (internal quotations omitted). If evidence is considered scientific, it must be based on a valid foundation. Id. at 561 (citing O’Key, 321 Or. 291-92). Courts screen scientific evidence before ruling on its admissibility using a number of enumerated factors. State v. Brown, 297 Or. 404, 417, 687 P.2d 751 (1984). The Court held that the trial court correctly considered the expert’s testimony scientific because the factfinder would have perceived the expert’s testimony as grounded in “conclusions that have been reached through application of a scientific method to collected data.” The Court further held that the foundation laid for the expert’s testimony did not meet the standards set by Brown and O’Key. Judgment affirmed.