State v. Ortiz, 528 P.3d 795

A 9‑1‑1 caller reported erratic driving; Officer Miguel located Ortiz at the scene, smelled alcohol, and observed watery eyes and emotional behavior.
Ortiz admitted drinking, said she felt "tipsy" and that she did not believe she was safe to drive; she denied driving the vehicle.
Miguel administered two field sobriety tests (walk‑and‑turn; one‑leg‑stand), observed multiple "clues," and arrested Ortiz; bodycam video of the encounter and FST performance was played for the jury.
A breath test about an hour later showed a .07% BAC (below the per se limit). Ortiz was convicted of DUII and appealed.
At trial Miguel testified (without objection) that FSTs are nationally standardized, designed to determine impairment, and supported by studies "proving their validity," and she stated Ortiz’s FST results were consistent with intoxication.
On appeal the Court of Appeals reviewed under plain‑error doctrine, held that the officer’s statements were scientific evidence admitted without the required Brown/O’Key foundation, found plain error, concluded the error was not harmless, and reversed and remanded for a new trial.

Issue	State's Argument	Ortiz's Argument	Held
Whether Miguel’s testimony that FSTs are nationally standardized and validated by studies constituted "scientific" evidence requiring a Brown/O’Key foundation	Miguel’s testimony was admissible as non‑scientific background and demonstrative of routine police procedure; any foundation could have been supplied	Testimony presented FSTs as scientifically validated and thus required a foundational showing of scientific validity under Brown/O’Key	Court: Testimony was scientific; trial court plainly erred by admitting it without foundation and should have excluded it sua sponte
Whether the admission of that scientific testimony was harmless and whether appellate court should exercise discretion to correct plain error	Any error was harmless given other evidence (odor, admissions, video); appellate court should not exercise discretion to reverse	The scientific characterization of FSTs had undue persuasive force separate from other evidence and was not harmless; reversal warranted	Court: Error was not harmless; exercised discretion to correct plain error and reversed and remanded

State v. Reid, 312 Or App 540 (Or. Ct. App. 2021) (officer’s pass/fail FST testimony deemed scientific; court found plain error)
State v. Eatinger, 298 Or App 630 (Or. Ct. App. 2019) (officer testimony that FSTs were product of scientific research treated as scientific evidence)
State v. Beltran‑Chavez, 286 Or App 590 (Or. Ct. App. 2017) (testimony that a subject passed/failed FSTs draws persuasive force from an objective scoring rubric and is scientific)
State v. O’Key, 321 Or 285 (Or. 1995) (courts must assess scientific validity of proffered scientific evidence under Brown/O’Key factors)
State v. Brown, 297 Or 404 (Or. 1984) (framework for evaluating admissibility of scientific evidence)
State v. Rambo, 250 Or App 186 (Or. Ct. App. 2012) (officer may offer intoxication opinions grounded in training and experience, so long as testimony does not imply scientific basis)
State v. Davis, 336 Or 19 (Or. 2003) (harmless‑error standards and inquiry into whether error affected the verdict)