dissenting.
The only issue before us is the admissibility of the HGN test as evidence at trial. In his findings of facts and conclusions of law, the trial judge concluded that the probative value of the evidence is outweighed by the danger of unfair prejudice because of the potential for error and the subjectivity of the test. He opined that the test may be of substantial probative value and helpful to the trier of fact in determining whether a defendant was under the influence of intoxicants and whether the blood alcohol content (BAC) was at least .08 percent. He found a serious potential for error, however, when the test is administered in the field. I agree.
The state argues that the HGN test is reliable and accurate. Defendant argues that the test is not accurate enough to be used to prove a specific BAC, and that the probative value of the evidence is outweighed by the danger of unfair prejudice.
*62In State v. Reed, 83 Or App 451, 732 P2d 66 (1987), we held that the HGN test is scientific evidence based on a novel scientific principle and that, in order for the results of the HGN test to be admissible as a field sobriety test, the state must lay a foundation for the scientific reliability and acceptance of the test. In State v. Scott, 121 Or App 308, 854 P2d 991 (1993), we reaffirmed that holding, rejecting the state’s argument that, under ORS 813.135 and ORS 801.272, the legislature approved admitting the results of the HGN test into evidence without an evidentiary foundation.
The Supreme Court articulated an analysis for admissibility of scientific evidence in State v. Brown, 297 Or 404, 687 P2d 751 (1984). Typically, scientific evidence is presented by an expert witness who can explain data or test results and, if necessary, the scientific principles that are said to give the evidence its reliability or accuracy. The Court elected to apply traditional standards to this expert testimony. 297 Or at 408.
Under the Oregon Evidence Code, expert testimony is admissible if it is relevant under OEC 4011 and if it will help the trier of fact in deciding a disputed issue. OEC 702.2 To identify and evaluate the probative value and the helpfulness of scientific evidence, the Court in Brown enumerated seven factors as guidelines:
“(1) The technique’s general acceptance in the field;
“(2) The expert’s qualifications and stature;
“(3) The use which has been made of the technique;
“(4) The potential rate of error;
“(5) The existence of specialized literature;
“(6) The novelty of the invention; and
*63“(7) The extent to which the technique relies on the subjective interpretation of the expert.” 297 Or at 417.
The court referred to additional factors that may be considered. Of that list, I consider the following factor appropriate to the evaluation of the HGN test and incorporate it into my analysis: “The extent to which the basic data are verifiable by the court and jury[.]” 297 Or at 417 n 5.
Even if evidence has probative value and is helpful to the trier of fact, it may still be excluded if it is unduly prejudicial, repetitive, or falls under some other exclusionary provision as provided in OEC 403.3 297 Or at 438. Regardless of the normal discretionary power of the trial judge in balancing the probative value of evidence against its prejudicial effect, the appellate courts retain the power to determine the admissibility of scientific evidence under the OEC.
The court received evidence on the admissibility of the test at an omnibus hearing on January 24, 1991. The parties stipulated that the court could also consider the testimony of witnesses received at an earlier hearing before the same judge in a different case. At the January 24, hearing, Dr. Yolton, a professor of optometry, along with the arresting officer,4 testified for the state, and Dr. Wolf, an ophthalmologist, testified for defendant. Testimony from an earlier hearing included that of Dr. Burns, a research psychologist, Dr. Brady, a consulting pathologist, Sergeant Studdard of the Los Angeles Police Department and Lieutenant Hayes of the Oregon State Police.
Yolton testified that nystagmus is a loss of steady fixation by the eyes on a target. In alcohol-induced nystagmus, also called jerk nystagmus, the eyes drift slowly in one direction and jerk back.
The rules for administering the HGN test are in OAR chapter 257. According to those rules, a trained officer is *64authorized to conduct the HGN test, in conjunction with certain other field tests, in order to determine if the driver is driving while under the influence of intoxicating liquor or with a blood alcohol content of greater than .08 percent, in violation of ORS 813.010. The officer holds a finger, pencil or penlight vertically in front of the person’s face, about 15 inches from the nose, and conducts any of the following three procedures deemed appropriate: (1) moving the stimulus to the side, checking for smooth pursuit (as opposed to drifting and jerking back); (2) checking for nystagmus at the maximum deviation of each eye;5 and (3) checking for the onset of nystagmus at approximately 40 degrees in each eye. OAR 257-25-020(l)(a).6
Reviewing the factors enumerated in Brown, I conclude that all of the experts are well-qualified and that Burns is nationally recognized for HGN testing research. The test is generally accepted by law enforcement authorities as a field sobriety test.7 Studdard stated that the test is accepted by law enforcement agencies to determine whether the person is under the influence of intoxicants but not as a way to determine BAC. Brady agreed that he would use it with other field sobriety tests to determine whether a person was impaired by alcohol, but not to determine a specific BAC.
Jurisdictions differ on the use of the HGN test as evidence in a criminal trial. Some jurisdictions allow a trained officer to testify about HGN test results without establishing an evidentiary foundation for the accuracy and reliability of the scientific principles. See, e.g., State v. Edman, 452 NW2d 169 (Iowa 1990); State v. Clark, 234 Mont 222, 762 P2d 853 (1988); State v. Nagel, 30 Ohio App 3d 80, 506 NE2d 285 (1986). In Arizona, the test may be used to establish probable *65cause for arrest and to corroborate or attack the accuracy of chemical tests, but not as independent evidence of blood alcohol content in the absence of a chemical analysis.8 State v. Superior Court, 149 Ariz 269, 276, 279, 718 P2d 171 (1986); see also State v. Garrett, 119 Idaho 878, 811 P2d 488 (1991); State v. Armstrong, 561 So 2d 883 (La App) writ den 568 So2d 1077 (La 1990). In Arizona, an officer may also testify in a criminal trial that the HGN test shows that a driver is under neurological dysfunction, one cause of which could be alcohol impairment, as long as there is no discussion regarding the accuracy of predicting a specific BAC. State ex rel Hamilton v. City Court of City of Mesa, 165 Ariz 514, 799 P2d 855 (1990).
The HGN test is not new and there is extensive literature about it, including reports of field studies and laboratory investigations. Yolton testified that the studies show that the HGN test is at least 80 percent accurate in predicting a .10 percent BAC and is more accurate than the other field sobriety tests. Burns testified that the 80 percent accuracy included other causes of HGN that were connected to nerve and muscle disfunction. Yolton testified that most of the literature suggests that if the alcohol level is .10 percent or more, the onset of jerk nystagmus will occur at approximately a 40 degree deviation from the nose.
There are a number of potential causes for misdiagnosis. A number of experts testified that nonalcohol induced jerk nystagmus caused by disease or brain damage occurs in three to four percent of the population, although it is generally nonsymmetrical (one eye only), whereas alcohol-induced nystagmus is the same in both eyes. Yolton testified that other drugs, such as depressants and convulsants, can cause HGN, and sleep loss can change the angle of onset by about five degrees. He also testified that if the officer moves the stimulus too rapidly or moves the stimulus slightly above the smooth pursuit line, the results will be distorted. Yolton referred to one authority who was critical of the test, because the test did not distinguish between alcohol-induced *66nystagmus and disease-caused nystagmus and because he did not believe that police officers would be properly trained in administering the test. Wolf testified that nystagmus can be produced by fatigue and anxiety and that, because there are so many possible causes of HGN, the test has very little value other than substantiating an impression that someone is under the influence of alcohol.
Brady testified that police car strobe lights would affect the test results. Wolf also testified that nystagmus can be caused in the field setting by strobe lights or lights from traffic on a busy highway.
Yolton testified that it is impractical to use a protractor in the field to measure 40 degrees but that, to obtain precise results, within plus or minus several degrees, it is probably necessary to use one. Wolf testified that, without using a protractor, the HGN test is not a scientific test. Hayes testified that an angle of onset of the nystagmus of 45 degrees correlates with a .05 percent BAC and that an angle of onset of 40 degrees suggests a BAC of .10 percent. Burns testified that, although the HGN test was demonstrably the most accurate and least subjective of all the field sobriety tests, the test is highly subjective, and she did not advocate using any one field sobriety test alone. In addition, the nature of the test administered in the field does not allow the judge or jury to verify the results. That issue was of major concern to the court in State v. Superior Court, supra, 149 Ariz at 279.
In summary, the use of the HGN test as a field sobriety test in conjunction with other field sobriety tests is well-documented and well established. The test is commonly used to establish probable cause to take a driver off the road. The evidence shows that it is relevant under OEC 401 and would be helpful to the trier of fact under OEC 702 to prove alcohol impairment. The issue is whether, under the balancing test of OEC 403, the test is accurate and reliable enough in predicting alcohol impairment that it is not outweighed by the danger of unfair prejudice or confusion of the issues when it is used to prove a violation of ORS 813.010.
I am concerned that there are causes for horizontal gaze nystagmus other than alcohol, including disease, fatigue and anxiety, that produce false positives. I am more troubled, *67however, that use of the test without calibrated instruments to insure the accuracy of the angle measured creates a serious potential for error and subjectivity. A difference of only five degrees in angle, between 40 and 45 degrees, can create a major difference in the expected test result, .10 BAC versus .05 BAC. The result also can be distorted in the field by police car strobe lights and other traffic lights, movement on the highway or by moving the stimulus too quickly or not on the smooth pursuit line. In addition, there is no way to verify the test results.
Considering the potential for error and subjectivity in performing the test in the field, I conclude that as proof of a violation of ORS 813.010, the probative value and helpfulness of the HGN test is greatly outweighed by the danger of unfair prejudice and confusion and the potential of the jury’s over-reliance on the scientific nature of the test.
Respectfully, I dissent.
OEC 401 provides:
“ ‘Relevant evidence’ means evidence having any tendency to make the existence of any fact that is of consequence to the determination of the action more probable or less probable than it would be without the evidence.”
OEC 702 provides:
“If scientific, technical or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training or education may testify thereto in the form of an opinion or otherwise.”
OEC 403 provides:
“Although relevant, evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury, or by considerations of undue delay or needless presentation of cumulative evidence.”
The parties stipulated that only the arresting officer’s January 24, 1991, testimony would be considered, not his testimony at an earlier hearing.
Yolton explained that this type of nystagmus is a significant exaggeration of nystagmus that occurs at the end of a person’s focus as the target moves to the side. The eyes will drift back toward the center and then jerk back to the side. The phenomenon normally occurs for a few seconds, but in alcohol-induced nystagmus, the condition will continue over an extended period, and the movements will be larger and are easy to distinguish.
The rule has since been amended to proivde that the officer shall check for the onsent of nystagmus “prior to 45 degrees in each eye.”
According to Burns, the National Highway Traffic Safety Association uses this test nationally, and about one-half of the states has adopted the field sobriety test battery that includes the HGN test.
The court found that, although the HGN test satisfied the evidentiary standard set forth in Frye v. United States, 293 F 1013 (DC Cir 1923), the test was fraught with due process problems, including a margin of error that would not satisfy proof of a crime beyond a reasonable doubt and the inability to duplicate the officer’s “reading” of the test.