State v. Henley, 422 P.3d 217

Background

Victim (11) testified that during a family camping trip defendant (stepfather) digitally penetrated her and rubbed his penis against her; she also described prior massages that made her uncomfortable and an earlier incident at age 5–6. Prosecutor emphasized massages as relevant.
State called Courtney Palfreyman, a forensic interviewer with social-work degrees and 10+ years’ experience, who described behaviors that "might be considered grooming," explained grooming as building trust to weaken defenses, and testified that the described massages "could be considered grooming." Defense objected to foundation under OEC 702.
Trial court admitted Palfreyman’s grooming testimony over defense objection and the jury convicted defendant of first-degree sexual abuse and attempted first-degree sodomy (acquitted on one count). Court of Appeals affirmed.
Oregon Supreme Court granted review to decide whether grooming testimony is "scientific" evidence under OEC 702 and thus required a foundational showing of scientific validity (per Brown and O'Key), and whether the admission was harmless.
Court held the grooming testimony was "scientific" under OEC 702 because (1) it implied grounding in behavioral science given the witness’s credentials and training, and (2) jurors were likely to perceive it as having scientific persuasive force; trial court erred by admitting it without a scientific foundation.
The Court declined to decide on the scientific validity of grooming literature via judicial notice, remanded for the trial court to develop the record, and reversed convictions as the error was prejudicial (not harmless).

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether expert testimony about "grooming" is "scientific" evidence under OEC 702	State: Palfreyman’s grooming evidence was experiential/specialized, not a scientific assertion, so no Brown/O'Key foundation required	Henley: Grooming testimony rests in behavioral science and would be perceived as scientific; requires foundational showing of scientific validity	Held: Grooming testimony was "scientific"—it implied a grounding in behavioral science and jurors would likely view it as scientific (OEC 702 applies)
Whether trial court erred by admitting grooming testimony without a scientific foundation	State: No error—testimony was nondiagnostic, experiential expert testimony	Henley: Error—state failed to establish scientific validity as required under Brown/O'Key	Held: Trial court erred by admitting grooming testimony without requiring proof of scientific validity/reliability
Whether the Supreme Court should decide scientific validity on review by judicial notice of literature	State: Court may take judicial notice and find grooming has sufficient scientific validity	Henley: Trial court should develop the evidentiary record; judicial notice inappropriate here	Held: Declined to decide scientific validity on appeal; remanded for trial court fact development rather than taking judicial notice
Whether the erroneous admission was harmless or prejudicial	State: Error harmless because independent evidence (victim’s testimony, prior incident, massages) supported sexual purpose	Henley: Testimony was central to credibility dispute and had persuasive scientific force; prosecutor used it substantively—error prejudicial	Held: Admission was not harmless; error likely affected verdict—reversed and remanded

Key Cases Cited

State v. Brown, 297 Or. 404 (1984) (scientific evidence draws convincing force from scientific principles; foundational reliability required)
State v. O'Key, 321 Or. 285 (1995) (scientific knowledge implies grounding in scientific method; jury perception of scientific weight matters)
State v. Marrington, 335 Or. 555 (2003) (expert testimony invoking research/literature is perceived as scientific and requires validation)
Jennings v. Baxter Healthcare Corp., 331 Or. 285 (2000) (clinical/diagnostic testimony bears the mark of science and must meet foundational standards)
State v. Hansen, 304 Or. 169 (1987) (testimony about grooming techniques has limited relevance and poses risk of unfair prejudice under OEC 403)
Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993) (scientific knowledge must be derived from the scientific method; factors for reliability)
State v. Perry, 347 Or. 110 (2009) (discussing acceptance of delayed-reporting phenomenon in evidentiary context)