People v. McKown

Docket No. 102372.

IN THE

SUPREME COURT

OF

THE STATE OF ILLINOIS

THE PEOPLE OF THE STATE OF ILLINOIS, Appellee, v.

JOANNE McKOWN, Appellant.

Opinion filed February 19, 2010.

JUSTICE GARMAN delivered the judgment of the court, with

opinion.

Chief Justice Fitzgerald and Justices Freeman, Thomas, Kilbride,

Karmeier, and Burke concurred in the judgment and opinion.

OPINION

Following a bench trial in the circuit court of Peoria County,

defendant was convicted of two counts of aggravated driving under

the influence of alcohol (DUI) (625 ILCS 5/11–501(d)(1)(C) (West

2006)), and other offenses. The appellate court affirmed (People v.

McKown, No. 3–04–0433 (2006) (unpublished order under Supreme

Court Rule 23)), and this court granted her petition for leave to

appeal. The single issue raised in her petition was whether she was

entitled to a hearing pursuant to the rule of Frye v. United States, 293

F. 1013 (D.C. Cir. 1923), before evidence of her performance on a

horizontal gaze nystagmus (HGN) test could be admitted. We held

that the trial court and the appellate court erred in taking judicial

notice that the HGN test is generally accepted as an indicator of

alcohol impairment and remanded to the trial court with instructions

to conduct a Frye hearing. People v. McKown, 226 Ill. 2d 245, 248

(2007) (McKown I). We retained jurisdiction and now review the trial

court’s judgment on that issue.

BACKGROUND

Under the rule of Frye, scientific evidence is admissible at trial

only “if the methodology or scientific principle upon which the opinion

is based is ‘sufficiently established to have gained general acceptance

in the particular field in which it belongs.’ ” In re Commitment of

Simons, 213 Ill. 2d 523, 529-30 (2004), quoting Frye, 293 F. at 1014.

Further, the Frye test is necessary only if the scientific principle,

technique or test offered by the expert to support his or her conclusion

is “new” or “novel.” See People v. Basler, 193 Ill. 2d 545, 550-51

(2000).

We held in McKown I that “[b]ecause the results of an HGN test

require expert interpretation” by a trained police officer, “the results

of HGN testing are scientific evidence.” McKown I, 226 Ill. 2d at 257.

We further held that, despite its use by police officers for many years,

“the methodology of HGN testing is novel for purposes of Frye.”

McKown I, 226 Ill. 2d at 258. Thus, a Frye hearing was necessary “to

determine if the HGN test has achieved general acceptance as a

reliable indicator of alcohol impairment.”1 McKown I, 226 Ill. 2d at

257. Finally, although we noted that it was appropriate in some

circumstances for a trial court to resolve the question of general

acceptance via judicial notice (McKown I, 226 Ill. 2d at 254), this

1

We note that this statement in McKown I was not intended to graft an

additional element of reliability onto the Frye test. As we observed in

Donaldson, “[t]he trial court is not required to conduct a two-part inquiry

into both the reliability of the methodology and its general acceptance.” The

question of reliability is “subsumed by the inquiry into its general acceptance

in the scientific community.” Donaldson v. Central Illinois Public Service

Co., 199 Ill. 2d 63, 81 (2002). See also In re Commitment of Sandry, 367

Ill. App. 3d 949, 966 (2006) (“once it is determined that a methodology is

generally accepted, it follows that it has achieved a sufficient degree of

reliability and validity to cross the threshold of admissibility”).

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particular issue could not be resolved “on judicial notice alone”

(McKown I, 226 Ill. 2d at 275). We remanded the matter to the trial

court for a Frye hearing to determine whether HGN testing is

generally accepted in the particular scientific field to which it belongs

as an indicator of alcohol impairment and to make findings of fact and

conclusions of law as to this question. McKown I, 226 Ill. 2d at 276-

77.

Nystagmus is “an involuntary, rapid, rhythmic movement of the

eyeball, which may be horizontal, vertical, rotatory, or mixed, i.e., of

two varieties.” Dorland’s Illustrated Medical Dictionary 1296 (30th

ed. 2003). The medical dictionary lists 45 types of nystagmus. For

example, ataxic nystagmus is unilateral and occurs in individuals with

multiple sclerosis. Dorland’s Illustrated Medical Dictionary 1296

(30th ed. 2003). Congenital nystagmus “may be caused by or

associated with optic atrophy, coloboma, albinism, bilateral macular

lesions, congenital cataract, severe astigmatism, and glaucoma.”

Dorland’s Illustrated Medical Dictionary 1296 (30th ed. 2003). Gaze

nystagmus, which is at issue in the present case, is “made apparent by

looking to the right or to the left,” as opposed to fixation nystagmus,

“which appears only on gazing fixedly at an object,” or latent

nystagmus, “which occurs only when one eye is covered.” Dorland’s

Illustrated Medical Dictionary 1296 (30th ed. 2003).

The methodology employed by law enforcement officers for

conducting an HGN testing as a part of field-sobriety testing is

explained in detail in our earlier opinion. In brief, the officer first

questions the subject to determine whether he or she has any medical

condition or is taking any medication that might affect the results of

the test. If not, the officer performs a preliminary test to determine

whether the pupils of the subject’s eyes are of equal size and whether

the eyes “track” equally as an object is moved, at eye level, from side

to side. If so, the HGN test itself is performed. The officer looks for

three “clues,” assessing each eye separately. The three clues are lack

of smooth pursuit, distinct nystagmus at maximum deviation, and the

onset of nystagmus at an angle less than 45 degrees. One point is

assigned for each clue that is present in either eye. Thus, the maximum

score is six, which would indicate all three clues present in both eyes.

A score of four or more is considered “failing” and indicative of

alcohol impairment. McKown I, 226 Ill. 2d at 249-50.

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The Evidence

The Frye hearing was held over the course of four dates between

March 2007 and April 2008. The State presented the testimony of Dr.

Carl Citek, Master Sergeant Antonio Lebron, Dr. Zenon Zuk, and

Thomas Page. Defendant presented the testimony of Dr. Joseph

Citron, Dr. Ronald Henson, and Dr. Steven Reubenzner. In addition,

each party submitted numerous journal articles and other writings in

support of its position. Finally, each party submitted a trial brief

arguing for certain findings of fact and conclusions of law.

Although the State had the burden on remand of demonstrating

that the HGN test meets the Frye standard (People v. Basler, 193 Ill.

2d 545, 551 (2000)), the presentation of evidence began with the

testimony of a witness called by the defendant.

Dr. Joseph Citron testified that he is a board-certified

ophthalmologist who received his clinical training at the Mayo Clinic

in Rochester, Minnesota. He practices in Atlanta, Georgia, and has

over 30 years experience in emergency medical care, including the

care of intoxicated patients. In 1999, he completed the National

Highway Transportation Safety Administration (NHTSA) training

course in field-sobriety testing, which included training in the HGN

test. He has 10 years of experience as an instructor on field-sobriety

testing for the Atlanta police department and other agencies. He also

holds a law degree.

Citron explained the differences in education and training between

an ophthalmologist and an optometrist, as well as the fact that an

optometrist does not perform surgery or medical diagnosis. He also

explained the meaning of the term “nystagmus,” which he described

as a condition that is “usually pathologic in origin” and “not part of

the normal findings in an individual.” Nystagmus itself is not a

diagnosis; it is merely a description of a certain type of eye movement

that may be caused by many conditions. He was unable to give a

specific number of recognized causes, but agreed with the statement

that the number is at least 39. Citron further testified that once an

individual had consumed sufficient alcohol to “reach the threshold of

central nervous system depression,” he could display nystagmus.

With regard to the HGN test performed by law enforcement

officers, Citron explained that the test is not performed in the same

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manner as the test a physician would perform during the examination

of a patient. He then explained that the NHTSA, which is a division

of the United States Department of Transportation, has promulgated

standards for performing the HGN test as a field-sobriety test. These

standards must be observed “in the same fashion every time by

everybody” and individual test results would be invalid if the test were

not performed in the “prescribed standardized fashion.” He then made

a presentation regarding the proper procedure for performing the

HGN test.

Citron testified that based on a “failed” HGN test alone, one could

not form an opinion that the cause of the failure was alcohol. The test

is a “preliminary test.” It is “the beginning of an evaluation, not the

conclusion.” Further, if one offered an opinion that the failure of the

test was caused by alcohol, that opinion would be conjecture or

speculation. Finally, Citron testified that a failed HGN test is a sign

that the subject’s central nervous system (CNS) is depressed. While

the cause of CNS depression might be recent consumption of alcohol,

the failed test is not an indicator of actual impairment due to alcohol.

On cross-examination by the State, Citron reiterated that HGN

can be an indicator of alcohol consumption and that an officer who

observes a failed HGN test can “put the presence of alcohol as a

central nervous system depressant on a list of possible causes for these

findings.”

The State’s case began with the testimony of Master Sergeant

Lebron of the Illinois State Police. He holds a bachelor’s degree in law

enforcement administration and, as part of his training to become a

state trooper, received training in the administration of standardized

field-sobriety tests. He testified that he spent 16 years as a patrol

officer. Lebron estimated that over the course of his career, he has

conducted close to 500 DUI investigations. Prior to taking his current

supervisory position, Lebron served as the breath-alcohol section

supervisor at the State Police Academy. In this capacity, he was

responsible for training new recruits in standardized field-sobriety

testing, including administration of the HGN test using the NHTSA

manual. A copy of the manual was introduced into evidence.

Lebron described conducting workshops at the Academy during

which some volunteers would consume differing amounts of alcohol

and others would be given a placebo as a control. The volunteers

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would take Breathalyzer tests to measure their blood-alcohol levels.

Then the trainees would perform field-sobriety tests on the volunteers.

During theses workshops, he observed that volunteers who had

consumed a sufficient amount of alcohol displayed HGN as well as a

degree of reduced motor skills. He has observed 400 to 500

volunteers being examined in such workshops.

He then testified that the HGN test, if performed according to the

standardized protocol, is generally accepted in the law enforcement

community as a reliable indicator of impairment due to alcohol. After

a defense objection, he clarified this statement to say that, in his

opinion, a failed HGN test is an indicator that the person has

consumed alcohol.

On cross-examination, Lebron acknowledged that he has seen

individuals fail all three of the field-sobriety tests when they had

absolutely no alcohol in their systems.

Dr. Karl Citek, a professor of optometry at Pacific University

College of Optometry in Forest Grove, Oregon, testified for the State.

He is involved in training police officers to perform standardized field-

sobriety tests and has observed these tests being performed in

controlled conditions. On one occasion, he accompanied patrol

officers and performed an HGN test in the field. On questioning by

defense counsel regarding his expert credentials, he acknowledged

that as an optometrist, he was not qualified to diagnose or treat any

of the several dozen conditions that may cause nystagmus.

After being accepted as an expert witness, Citek testified that

optometrists have a “better feel for the test” than ophthalmologists

because “when nystagmus occurs because of an outside influence ***

visual function is reduced.” He also testified regarding a resolution

adopted in 1993 by the American Optometric Association (AOA)

House of Delegates endorsing the HGN test as a valid and reliable

field-sobriety test. He stated that the resolution was renewed in 2006

and that he agrees with the resolution.

On cross-examination, Citek acknowledged that lack of smooth

pursuit could be exhibited by a subject with a blood-alcohol

concentration as low as 0.02 and that nystagmus at maximum

deviation could be exhibited by a subject with a blood-alcohol

concentration as low as 0.04. Thus, a subject could be given a “failing

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score” on the HGN test with a blood-alcohol concentration at half the

statutory limit of 0.08 (625 ILCS 5/11–501(a)(1) (West 2006)). Citek

noted, however, that some individuals could be intoxicated at this

level.

With regard to officer training, Citek acknowledged that an officer

could pass the standard written test following training in field-sobriety

testing by answering 16 of 20 questions correctly and that only four

of the 20 questions relate to HGN testing. Thus, an officer could

answer all questions concerning HGN testing incorrectly and still

receive certification in field-sobriety testing. Citek noted that in

addition to passing the written test, officers must perform HGN tests

at a live workshop to demonstrate proficiency before being certified.

He was unable to answer further questions about the test and the

testing procedure because, although he had read the NHTSA training

manual, he himself had not completed the training.

On the question of the American Optometric Association

resolution, Citek testified that he was not present at the 1993 annual

meeting at which the resolution was adopted. He did not know if the

resolution was debated prior to being voted upon or how the vote was

taken, by head count or by acclamation.

The State next presented the testimony of Dr. Zenon Zuk, medical

director of the Los Angeles County/University of Southern California

Employee Health Care System. Zuk was previously employed as staff

physician at the Los Angeles County jail, where he performed more

than 7,000 medical evaluations on arrestees admitted to the jail. These

evaluations included an assessment of whether the arrestee was under

the influence of alcohol or other drugs.

Zuk testified that, in his opinion, a finding of HGN is generally

accepted in the medical community as an indicator of alcohol-induced

CNS impairment. If he were to observe HGN during the examination

of a patient, he would inquire about the ingestion of drugs and/or

alcohol within in the previous 12 to 24 hours. He stated that he could

not make a diagnosis solely on the basis of HGN, but that the test is

a “linchpin” in determining whether a patient’s CNS is impaired.

He also testified that police officers can be trained to administer

the test correctly and to observe the presence of HGN. He opined that

the HGN test used by law enforcement is “more rigid,” “more

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formal,” and “more methodical” than the HGN test used by

physicians.

Zuk stated that there are 35 to 40 different forms of nystagmus

and explained at length how these can be distinguished from HGN. On

cross-examination, however, he acknowledged that nystagmus might

be a symptom of as many as 125 diseases or conditions. He stated on

redirect examination that while these conditions could cause

nystagmus, it would not manifest “in the exact same way as HGN.”

Further, many of the diseases or conditions on this list are rare and

perhaps 80% of them would not be seen by a practicing physician “in

a lifetime of practice.”

Finally, Zuk acknowledged that the HGN test was originally

validated as a test for estimating a person’s blood-alcohol

concentration, not as a measure of driving impairment.

Thomas Page testified for the State that he served as a police

officer for 22 years in Detroit and Los Angeles. He has administered

the HGN test in the field and has observed other officers doing so. He

trains police officers and others to perform the test and to interpret the

results. He opined that the test is “universally” accepted within the law

enforcement community as a reliable indicator of alcohol impairment.

He testified that in his experience, the presence of HGN has

corresponded to the presence of an impairing level of alcohol in the

subject’s system. He did not, however, provide any data in support of

this statement. He acknowledged that he could not speak to the

question of general acceptance of HGN testing within the scientific or

medical communities.

At the conclusion of the State’s case, the defendant presented her

remaining witnesses.

Dr. Ronald Henson is a former police officer who was among the

first officers to receive NHTSA training on HGN testing in Illinois.

His doctorate is in the field of applied management and decision

sciences. He has been an instructor on field-sobriety testing at the

Police Training Institute at the University of Illinois and has taught the

physiology and pharmacology of alcohol at Bradley University. He is

familiar with HGN research, having collected papers and articles on

the subject for over 25 years, and he has written and lectured on the

subject.

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He testified that the test was designed to estimate the subject’s

blood-alcohol concentration , not to reveal impairment, and that it has

not been accepted in the academic community as a reliable indicator

of alcohol impairment because it cannot discriminate between those

who have merely consumed alcohol and those who have consumed

too much.

He further testified to his opinion that Illinois’ training of police

officers on the subject of field-sobriety testing is inadequate. While the

NHTSA recommends a 24-hour course, Illinois devotes only four to

six hours to the entire three-test battery of field-sobriety tests. Only

one hour is devoted to HGN. Further, the NHTSA-approved written

test contains 20 questions on field-sobriety tests while the Illinois test

contains six or fewer such questions. Illinois does not require that

officers undergo retraining or recertification in field-sobriety testing.

Based on his review of videotapes of actual Illinois arrests, he opined

that only 1 in 100 field HGN tests is properly administered.

Dr. Steven Rubenzer testified that he is a board-certified forensic

psychologist. He has completed both the NHTSA student course and

its instructor course. He has published several peer-reviewed articles

relating to HGN testing.2 Based on a survey of psychologists that he

conducted, he testified that HGN testing is not generally accepted in

his field as an indicator of intoxication and that there are no academic

studies validating the test as a measure of impairment.

He pointed to the lack of peer-reviewed literature on the subject

by ophthalmologists and optometrists and to what he described as

flaws in the methodology of the original research study on this subject.

See M. Burns & H. Moskowitz, Psychophysical Tests for DWI

Arrest, DOT HS-802 424, June 1977, U.S. Department of

Transportation, National Highway Traffic Safety Administration. A

later article by Burns stated that a more recent study showed that 20

out of 26 people who failed the test had a blood-alcohol concentration

2

Defendant states in her brief that this court “referred to” an article by

this witness in its opinion in McKown I. While this statement is literally true,

we “referred” to the article only as being on her “extensive list of articles that

condemn the reliability of HGN testing.” McKown I, 226 Ill. 2d at 273. We

did not, in any sense, endorse or rely on the article.

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below 0.08, which he described as a false positive error rate of 67%.

He also described a 1981 study showing “interrater reliability” of only

0.66. That is, when the subject was examined by two police officers,

the officers’ judgment of impairment was the same in only two-thirds

of cases. He opined that a interrater reliability coefficient of less than

0.80 rendered the test unreliable.

On cross-examination, Rubenzer acknowledged that his peer-

reviewed article cited a journal called “Journal of Optometry and the

Law,” which does not exist. He further acknowledged that he has not

conducted any research studies on the HGN test and that he has no

medical training. His survey of psychologists was conducted on-line.

Of 64 board-certified psychologists who responded to his query, 53

stated that they believed that HGN testing was not generally accepted

in their field.

The Trial Court’s Findings of Fact and Conclusions of Law

In brief answer, the trial court concluded that “the clinical HGN

test is generally accepted in the scientific world of ophthalmology and

optometry as a reliable (preliminary) indicator of alcohol impairment.”

While acknowledging that the roadside HGN test as performed by law

enforcement officers “has been questioned as to its general acceptance

and reliability,” the trial court noted that the “scientific principle itself

is unquestioned.” In addition, the trial court found that the HGN test,

when properly conducted by a trained police officer, “has been shown

to be a sufficiently reliable component of field-sobriety testing that

assists the police officer in making the decision to arrest and to

formulate an opinion (along with other evidence) of whether a person

is operating a motor vehicle under the influence.”

At the conclusion of its summary of the evidence presented, the

trial court made five enumerated conclusions of law:

“1. HGN testing satisfies the Frye standard in Illinois.

2. HGN testing is but one facet of field sobriety testing

and is admissible as a factor to be considered by the trier-of-

fact on the issue of alcohol or drug impairment.

3. A proper foundation must include that the witness has

been adequately trained, has conducted testing and assessment

in accordance with the training, and that he administered the

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particular test in accordance with his training and proper

procedures.

4. [Testimony regarding] HGN testing results should be

limited to the conclusion that a “failed” test suggests that the

subject may have consumed alcohol and may [have] be[en]

under the influence. There should be no attempt to correlate

the test results with any particular blood-alcohol level or range

or level of intoxication.

5. In conjunction with other evidence, HGN may be used

as a part of the police officer’s opinion that the subject [was]

under the influence and impaired.” (Emphasis in original.)

ISSUES PRESENTED

Defendant argues that: (1) the HGN test is not a reliable indicator

of impairment due to alcohol and, therefore, does not meet the Frye

standard; (2) even if the HGN test does meet the Frye standard,

admissibility of test results should be limited to showing probable

cause for arrest; (3) if HGN test results are admissible at trial, the

court must strictly enforce standards for performance of the test; (4)

police officers who testify regarding HGN test results are testifying as

expert witnesses and should not be considered qualified unless they

have received extensive training; (5) the trial court’s findings of fact

in the Frye hearing were erroneous; and (6) the HGN test results

should not have been admitted at her trial because the officer did not

properly administer the test.

The State responds that the HGN test does meet the Frye standard

and that use of this evidence should not be limited to establishing

probable cause. In response to defendant’s third and fourth arguments,

the State argues that this court should adopt the trial court’s

foundational requirements for admissibility. The State also argues that

defendant has forfeited her final argument by failing to raise the issue

in her petition for leave to appeal.

ANALYSIS

At the Frye hearing, the burden was on the State to demonstrate

that HGN testing is generally accepted in the relevant scientific field

as an indicator of alcohol impairment. People v. Miller, 173 Ill. 2d

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167, 187-88 (1996) (proponent of evidence predicated upon a

scientific theory bears the burden of demonstrating that the theory

relied upon by the expert has gained general acceptance in the expert’s

scientific field). We review the trial court’s conclusion that the State

has met this burden de novo. In doing so, we may “consider not only

the trial court record but also, where appropriate, sources outside the

record, including legal and scientific articles, as well as court opinions

from other jurisdictions.” Commitment of Simons, 213 Ill. 2d at 531.

We note that the various witnesses, although knowledgeable and

experienced, were not altogether objective. Each has a stake of some

sort in the outcome of this debate. Thus, we are guided more by the

points on which they agree than by any points of disagreement.

Challenge to the Trial Court’s Findings of Fact

Defendant argues that the findings of fact upon which the trial

court’s conclusion was based are erroneous. She takes particular

exception to the trial court’s uncritical acceptance of the American

Optometric Association’s resolution and its reliance on case law from

other states that predates some of the more current scientific

literature.

In its written findings of fact, the trial court stated that the “long-

standing resolution of the American Optometric Association declaring

the HGN test ‘to be a scientifically valid and reliable tool for trained

officers to use in field sobriety testing’ is compelling evidence showing

a sufficient consensus in the scientific community to allow HGN

testimony in Illinois courts.”

The resolution was introduced into evidence via the testimony of

Citek, who, on cross-examination, could provide no background

information regarding the purpose for which it was proposed, the

circumstances under which the resolution was adopted, or the debate,

if any, over the proposal.

The American Optometric Association is a professional

organization, not a scientific body. Its goals are to set professional

standards, lobby government and other organizations on behalf of the

profession, and to provide leadership for research and education. See

http://www.aoa.org (last visited February 1, 2010). According to

Citek’s testimony, not all members of the profession are members of

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the Association.

We do not believe that a resolution adopted by the members of a

professional organization can be considered evidence of consensus

among the members of that profession. Of the 36,000 actual members,

it is likely that a fraction were present at the American Optometric

Association House of Delegates in 1993 when this resolution was

adopted and when it was subsequently reaffirmed. The record contains

no information as to the number of members voting for or against the

resolution. Thus, rather than expressing general acceptance, the

resolution expresses the opinion of a relatively small number of

members of the profession.

Further, the purpose of the American Optometric Association

resolution was to urge doctors of optometry to “become involved as

professional consultants in the use of HGN field sobriety testing.”

Thus, rather than expressing a considered professional opinion on the

science underlying HGN testing, the resolution expressed an interest

in urging members to take advantage of a professional opportunity

being created by the emerging acceptance of HGN testing by law

enforcement agencies.

Thus, we agree with the defendant on this point and give no

weight whatsoever to the Association’s resolution.

Each party provided the trial court with journal articles and other

literature in support of its position. The State introduced into evidence

a volume entitled “DWI Detection and Standardized Field Sobriety

Testing” (cited therein as DOT HS 178 R2/06), published by the

NHTSA as a training manual for students participating in training for

field-sobriety testing. Six pages of the volume are devoted to the

subject of nystagmus. The volume outlines a 10-step procedure for

performing a field test for HGN. DOT HS 178 R2/06, at VIII-7.

The volume also contains a bibliography listing 34 “Scientific

Publications and Research Reports Addressing Nystagmus.” The

actual reports and publications are not included. Given this lack of

content regarding the science underlying HGN field testing, we find

nothing in this volume relevant to the question of general acceptance

in the relevant scientific field.

The State also submitted journal articles by several of its expert

witnesses and others on the subject of HGN testing and the

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relationship of HGN to impairment due to consumption of alcohol or

other drugs. Many of these publications were prepared under contract

to the NHTSA.

In addition, the State provided the report of the initial 1977

laboratory study that has served as the basis for the widespread

adoption of HGN field testing. The study was sponsored by the

NHTSA for the purpose of evaluating the field-sobriety tests being

used by police officers at that time, identifying tests that would

provide the most reliable evidence of a blood-alcohol concentration

above the legal limit, and standardizing the procedures for

administering these tests. M. Burns & H. Moskowitz, Psychophysical

Tests for DWI Arrest, DOT HS-802 424, June 1977, U.S. Department

of Transportation, National Highway Traffic Safety Administration.

Ten officers administered a battery of six tests, including HGN, to 238

subjects. Some of the subjects were given alcohol prior to testing;

others were given a placebo. The subjects’ blood-alcohol

concentrations were measured and shown to be in the zero to 0.15

range. The officers were instructed to arrest any subject they believed

to have a blood-alcohol concentration of 0.10 or higher, based on the

results of six field-sobriety tests. They made correct arrest decisions

in 76% of cases. Analysis of the data led to the recommendation that

accuracy could be improved by reducing the number of tests to a

battery of three: one-leg stand, walk-and-turn, and HGN.

Based on our review of the initial study and the other articles

provided by the State, several themes emerge. First, alcohol and CNS-

depressant drugs affect the neural centers in the brain that control eye

movements, as well as other centers of the brain. Second, HGN

correlates highly with both an elevated blood-alcohol concentration

and with cognitive impairment. Third, an individual may fail the HGN

test by showing 4 or more clues despite a blood-alcohol concentration

below the legal limit for driving. Such a person may or may not be

impaired for driving. Fourth, to be a reliable indicator of alcohol

consumption, HGN field testing must be performed in accordance

with the NHTSA protocol. Fifth, police officers can be trained to

distinguish HGN due to consumption of alcohol or other substances

from some other common forms of nystagmus.

Defendant argues that the literature she provides is more current

than that relied upon by the State and that, as a result, it calls into

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doubt continued reliance on HGN testing as a field-sobriety test,

despite acceptance by several state courts in the years after the initial

1977 study.

Several articles written by expert witness Rubenzer are provided.

The articles are descriptive, in that they summarize research done by

others rather than report on independent research. In brief summary,

these articles conclude that HGN testing is being improperly used by

law enforcement. The HGN field test was originally developed by

Burns and others as a tool to screen drivers to determine whether

blood-alcohol concentration testing was justified. The test was not

designed to determine whether the subject is impaired for driving and

its use for this purpose has not been validated by controlled studies.

Further, Rubenzer asserts that the developers of the test, along with

prosecutors, have “oversold” the test.

Among the other articles provided by defendant, several are taken

from defense-oriented journals and others from the Web sites of

attorneys who engage in DUI defense practice.

While the points made by Rubenzer and others are worth noting,

we find nothing in the materials provided by defendant to contradict

the five general points listed above that we found supported by the

literature provided by the State.

In sum, while we agree with defendant that the American

Optometric Association’s resolution is not worthy of consideration

under Frye, we reject her assertion that the trial court’s findings of

fact are erroneous. In any event, because we are engaged in de novo

review, we are not bound by those findings.

Relevant Scientific Field

A review of the evidence presented reveals that HGN is a physical

sign that reveals, among other things, the existence of CNS

depression. Thus, the underlying basic science is the physiology of the

CNS. Practitioners such as neurologists, ophthalmologists, and

optometrists are trained to perform this test in a clinical setting and to

observe the results and, in the case of physicians, to diagnose and treat

conditions that cause nystagmus.

As noted above, in the 1970s, the NHTSA sponsored research by

psychologist Dr. Marcelline Burns of the Southern California

-15-

Research Institute into the reliability of field-sobriety testing. Based

on her research, which found a correlation between the ingestion of

alcohol and the presence of HGN, law enforcement agencies adopted

this clinical test for use as a field-sobriety test.

Lebron and Page testified that HGN testing is generally accepted

within the law enforcement community as a field-sobriety test. Law

enforcement, however, is not a scientific field. Therefore, general

acceptance within law enforcement circles cannot be the basis for

finding scientific evidence admissible under Frye.

The trial court found that the relevant scientific fields to which the

HGN test belongs are optometry and medicine, specifically the

medical specialty of ophthalmology.

We agree with the trial court that the relevant scientific fields that

embrace the testing for and observation of HGN include medicine,

ophthalmology, and optometry. Research and expert opinion in other

scientific or medical fields, such as neurophysiology, might also be

relevant.

Thus, the question of general acceptance must be determined from

the testimony of experts and the literature in these scientific fields, and

not from the testimony or writings of law enforcement officers or

agencies.3 Similarly, despite Dr. Henson’s years of experience, his

3

Some Illinois cases have phrased the Frye test in terms that would seem

to require the expert witness whose testimony is used to admit the scientific

evidence at trial to be a member of the scientific field to which the scientific

evidence belongs. See, e.g., In re Marriage of Gambla, 367 Ill. App. 3d 441,

460 (2006) (stating that under Frye, “the proponent of expert testimony

predicated upon a scientific theory must establish that the theory has gained

general acceptance in the expert’s scientific field” (emphasis added)).

This has never been a requirement under Frye, which requires the court

to determine whether the science underlying a witness’s testimony is

generally accepted in the relevant scientific field. Whether the testifying

witness is qualified to give the scientific testimony is a separate question.

Thus, a police officer trained as an accident-reconstruction expert may

be qualified to testify regarding the use of certain principles of physics to

determine how fast a vehicle was traveling at the moment of impact, even

though the expert is not a physicist. So long as the scientific principles being

applied are generally accepted in the field to which they belong–physics–the

-16-

professional credentials do not qualify him as an expert on the general

acceptance of HGN testing for the purpose of alcohol impairment

within these scientific fields.

General Acceptance

Defendant argues that the presence of HGN is not a reliable

indicator of impairment due to alcohol. She points to testimony that

the presence of HGN correlates with blood-alcohol concentrations of

0.04 to 0.06, which is lower than the statutory definition of

intoxication. The State responds that defendant was not charged with

driving with a blood-alcohol concentration over the legal limit (625

ILCS 5/11–501(a)(2) (West 2006)); she was charged with aggravated

DUI (625 ILCS 5/11–501(d)(1)(C) (West 2006)), and that a driver

may be impaired with a blood-alcohol concentration below 0.08.

Defendant also argues that an individual may fail the HGN test due

to as many as 125 conditions unrelated to alcohol ingestion. The State

answers that the testimony clearly shows that the eye movements

elicited by the HGN test are readily distinguishable from other forms

of nystagmus and that these differences are obvious to a properly

trained observer.

These points of disagreement and the issues raised at oral

argument reveal that before we can determine whether a scientific

principle is generally accepted, we must define the purpose for which

it is being used at trial. Our remand for a Frye hearing directed the

trial court to determine whether a failed HGN test was generally

accepted in the relevant scientific community as an indicator of

impairment due to alcohol. McKown I, 226 Ill. 2d at 276.

The testimony by witnesses for both parties consistently stated

that the presence of the physical sign of HGN is indicative of CNS

depression due to the consumption of alcohol. This sign may also

indicate some other form of CNS depression. There is also general

otherwise qualified expert may testify regarding those principles.

Similarly, our conclusion that the science of HGN testing belongs to the

fields of medicine and optometry for purpose of the Frye hearing does not

preclude a police officer from testifying regarding the performance of the test

and the results observed.

-17-

agreement among the testifying experts that when the subject has

consumed alcohol, HGN is not necessarily a sign of impairment as a

result of that alcohol consumption.

The trial court concluded that “both ophthalmology and optometry

generally accept the principle that the HGN test may be an indicator

of alcohol consumption.” The trial court stated, further, that the use

of HGN test results at trial “should be limited to the conclusion that

a ‘failed’ test suggests that the subject may have consumed alcohol

and may [have] be[en] under the influence. There should be no

attempt to correlate the test results with any particular blood-alcohol

level or range or level of intoxication.”

We agree. Consumption of alcohol is a necessary precondition to

impairment due to alcohol. Therefore, any evidence of alcohol

consumption is relevant to the question of impairment. See People v.

Beaman, 229 Ill. 2d 56, 75-76 (2008) (stating that evidence is relevant

if it tends to make the existence of any fact in consequence more or

less probable than it would be without the evidence); Black’s Law

Dictionary 1404 (9th ed. 2009) (defining relevant as “[l]ogically

connected and tending to prove or disprove a matter in issue”). A

failed HGN test is relevant to impairment in the same manner as the

smell of alcohol on the subject’s breath or the presence of empty or

partially empty liquor containers in his car. Each of these facts is

evidence of alcohol consumption and is properly admitted into

evidence on the question of impairment.

We, therefore, adopt the trial court’s finding that HGN testing is

generally accepted in the relevant scientific fields and that evidence of

HGN test results is admissible for the purpose of proving that a

defendant may have consumed alcohol and may, as a result, be

impaired.

Decisions of Our Sister States

Our conclusion that HGN testing is generally accepted is

consistent with that of other states that have conducted Frye hearings

on this question. See Ballard v. State, 955 P. 2d 931 (Alaska App.

1998) (HGN test results admissible to show that a defendant has

consumed alcohol and is potentially impaired); State v. Superior

Court, 149 Ariz. 269, 718 P.2d 171 (1986) (holding that with proper

-18-

foundation, testimony regarding nystagmus is admissible as evidence

that a defendant was driving while under the influence of alcohol);;

People v. Joehnk, 35 Cal. App. 4th 1488, 42 Cal. Rptr. 2d 6 (1995)

(when combined with results of other field-sobriety tests and with the

officer’s observations, HGN is a useful tool in reaching opinion as to

whether a defendant is intoxicated); State v. Klawitter, 518 N.W.2d

577 (Minn. 1994) (HGN testing satisfies Frye test); State v. Baue, 258

Neb. 968, 607 N.W.2d 191 (2000) (HGN evidence admissible for

limited purpose of showing the defendant had an impairment that may

have been caused by alcohol, but not admissible for proving blood-

alcohol concentration in excess of legal limit); State v. Baity, 140

Wash. 2d 1, 991 P.2d 1151 (2000) (use of HGN as forensic test to

determine intoxication satisfies Frye).

Defendant argues that reliance on these cases is misplaced either

because the cases have been undermined by later developments or

because the Frye issue was not as fully litigated, as it has been in the

present case. Because we do not rely on these cases as support for our

holding, but merely acknowledge that our conclusion is consistent

with them, we reject defendant’s argument that our reliance on these

cases is misplaced.

Limits on Admission of HGN Evidence at Trial

Defendant argues that the use of HGN evidence should be limited

to use at a preliminary hearing to establish probable cause to arrest.

She argues that the HGN test is not sufficiently reliable to be used as

evidence of guilt because it does not prove impairment beyond a

reasonable doubt. Defendant cites no authority for imposing such a

limitation but urges this court, as “gatekeeper of evidence,” to declare

that HGN test results may not be used at trial.

Defendant overlooks the threshold requirement of relevance. Each

individual item of evidence does not have to prove the fact at issue

beyond a reasonable doubt. Rather, each individual item of evidence

must tend to show that the fact at issue, in this case impairment due

to alcohol, is more or less likely. By way of analogy, it is often said

that “ ‘a brick is not a wall.’ ” Fed. R. of Evid. 401, Advisory

Committee’s Note, quoting C. McCormick, Handbook of the Law of

Evidence §152, at 317 (1954). That is, an individual item of evidence

-19-

is merely a brick, one of many bricks used to build the wall that is the

fact at issue.

The police officer’s testimony regarding the results of a

defendant’s failed HGN test tends to show that he or she consumed

alcohol prior to being tested. Similarly, testimony that a defendant did

not display any sign of HGN is relevant evidence that tends to show

that he or she had not consumed alcohol. The result of the test,

therefore, makes it either more or less likely that a defendant was

impaired due to alcohol.

This is the concern addressed by the trial court’s conclusion that

the use of HGN evidence should be limited to proof of alcohol

consumption and the possibility of resulting impairment. Limitation

may take the form of sustaining an objection to certain questions or

arguments made by the prosecutor, giving a limiting instruction at the

time the testimony is given, or giving a written jury instruction at the

conclusion of the case. The need for a limitation on the use of the

evidence, however, is not a basis for finding the evidence inadmissible

at trial under the test of Frye.

We, therefore, reject defendant’s invitation to limit the use of this

relevant piece of evidence to showing probable cause.

Defendant also argues that despite its relevance, a failed HGN test

result “proves too much” because of its “aura” of scientific certainty.

In effect, she is arguing that the risk of undue prejudice from this

evidence substantially outweighs its probative value. See People v.

Walker, 211 Ill. 2d 317, 337 (2004) (“Illinois courts have long

recognized, as a matter of common law, that a trial court may exercise

its discretion to exclude evidence, even when it is relevant, if its

prejudicial effect substantially outweighs its probative value”).

This balancing of risk of prejudice versus probative value is not

performed across the board. It is necessarily a case-by-case analysis.

Our finding that HGN evidence meets the Frye standard does not

preclude the possibility that, in a given case, the trial court might rule

such evidence inadmissible on grounds of undue prejudice.

Defendant also asserts that there is insufficient oversight of police

officers who administer the HGN test in the field, particularly with

regard to their qualifications and their ability to interpret the test

results. She argues that field studies and anecdotal evidence suggest

-20-

that the “vast majority” of police officers improperly perform the test

in arrest situations. In light of this, she argues for more extensive

training of police officers and for stricter standards regarding the

procedure for performing the test in the field. Specifically, she claims

that if HGN evidence does meet the Frye standard, the only

acceptable method for administering the HGN test by a police officer

is the NHTSA method.

This argument merges two separate questions: first, the proper

method for conducting HGN testing in the field and, second, the

qualifications of the witness who will testify regarding the HGN test

results.

The trial court framed the question before it on remand in terms

of the general acceptance of the “NHTSA roadside HGN test.” The

evidence presented by both parties was geared toward the test as

developed and taught by the NHTSA. Thus, the trial court’s ruling on

the Frye issue necessarily imported the NHTSA standard testing

protocol. Our adoption of the trial court’s conclusion is similarly

limited.

We hold that evidence of HGN field-sobriety testing, when

performed according to the NHTSA protocol by a properly trained

officer, is admissible under the Frye test for the purpose of showing

whether the subject has likely consumed alcohol and may be impaired.

As for the qualifications of the individual witness, the trial court

concluded that a proper foundation must be laid, including a showing

that the witness is properly trained and that he performed the test in

accordance with proper procedures.

We agree. A properly trained police officer who performed the

HGN field test in accordance with proper procedures may give expert

testimony regarding the results of the test. We also agree with the trial

court’s conclusion that a testifying officer may use the HGN test

results as a part of the basis for his opinion that the defendant was

under the influence and impaired.

In sum, we affirm each of the trial court’s five conclusions of law.

Whether the HGN Test Was Properly Administered by the Officer

in This Case

Defendant’s final argument is that even if evidence of HGN field

-21-

testing is generally admissible under Frye, the evidence should not

have been admitted against her because the test was not administered

by Officer Klatt in compliance with NHTSA standards. Specifically,

she argues that Klatt did not testify that he checked her eyes for equal

tracking before conducting the HGN test. He did not testify that he

checked her eyes for equal pupil size. He did not describe the speed

at which he moved the stylus or that he held the stylus at the point of

maximum deviation for the requisite four seconds. He did not testify

that he repeated the procedure twice, as NHTSA protocol requires.

Finally, he confused two of the clues when he combined two steps in

the protocol. As a result, defendant argues, Klatt’s testimony

regarding the HGN test should have been excluded and, further, he

should not have been allowed to express an opinion that she was

impaired because his opinion was necessarily based on the result of the

improperly performed test. She argues further that because the trial

court relied “heavily” on this evidence, her conviction should be

reversed. Finally, she argues that a new trial is barred by double

jeopardy.

The State argues that defendant forfeited any argument on this

issue by failing to raise it at trial and in a posttrial motion. People v.

Enoch, 122 Ill. 2d 176, 186 (1988). The State notes that because the

defendant failed to raise this issue at trial, it was deprived of the

opportunity to cure any defect in the officer’s foundation testimony at

that time. People v. Bush, 214 Ill. 2d 318, 333 (2005).

In her brief to the appellate court, defendant argued that the State

failed to present an adequate foundation for the results of her HGN

test to be admitted. She did not argue that trial counsel was ineffective

for failing to make a timely objection and to raise the issue in a

posttrial motion. She did not argue that admission of the officer’s

testimony regarding HGN was plain error.

The State, however, failed to bring defendant’s forfeiture of the

issue to the attention of the appellate court. In effect, the State

forfeited its ability to argue forfeiture by the defendant. People v.

Williams, 193 Ill. 2d 306, 347 (2000) (doctrine of forfeiture applies

to the State as well as to the defendant and State may forfeit claim

that the defendant forfeited an issue by not properly preserving it for

review).

The appellate court addressed the issue on the merits, finding that

-22-

a sufficient foundation was presented for the admission of the test

result.

In her petition for leave to appeal, defendant raised only the single

issue of the necessity for a Frye hearing. On this issue, she prevailed

and was granted remand for a Frye hearing.

At the Frye hearing, defense counsel attempted to question Dr.

Citron as to whether Klatt correctly performed the HGN test

according to NHTSA standards. The State objected. Counsel

explained that his position was that while an HGN test performed

according to these standards might meet the Frye standard for

admissibility, the test as performed by the officer in this case did not

meet the Frye standard. The trial court sustained the objection,

reasoning that if the Frye hearing had been held at trial, the question

of admissibility of HGN testing in general would have been resolved

prior to the receipt of the officer’s testimony. Thus, the question on

remand was to be answered as a general matter. Any question

regarding the admissibility of a specific test in an individual case was

one to be answered at trial. Defense counsel was allowed to make an

offer of proof. Citron testified that he had reviewed the transcript of

Officer Klatt’s testimony and that the examination as described by

Klatt did not follow the NHTSA standardized protocol for HGN

testing. As a result, he opined, the test was invalid.

Similarly, defense counsel was allowed to make an offer of proof

during cross-examination of Master Sergeant Lebron. Lebron

reviewed the transcript of Officer Klatt’s trial testimony and stated

that Klatt performed the test while defendant was seated; while the

NHTSA manual requires that the subject be standing. Further, Klatt’s

testimony does not indicate that he questioned defendant about any

eye problems, equal tracking, equal pupil size, or resting nystagmus.

Lebron stated that he “would agree” with the statement that Klatt did

not perform the test in accordance with NHTSA standards.

During its cross-examination of Dr. Citek, the defense again made

an offer of proof regarding the manner in which Klatt conducted the

HGN test in this case. Citek acknowledged that the officer’s testimony

did not state that he observed equal pupil size and equal tracking

before he conducted the HGN test and that if the officer did skip these

steps, the test results would not be reliable.

-23-

Page acknowledged that the HGN test must be performed

according to NHTSA standards to be considered reliable as a field-

sobriety test and that he has seen trained police officers administer the

test incorrectly. He agreed that Klatt’s trial testimony did not correctly

describe the clues one observes when administering the HGN test.

Dr. Henson reviewed Klatt’s testimony and stated based on that

testimony, the test Klatt performed was not in compliance with

NHTSA standards.

Notwithstanding the testimony on remand in which even the

State’s witnesses found Klatt’s testimony insufficient to lay the

foundation for HGN evidence, the State argues that because defendant

failed to raise the issue in her petition for leave to appeal, she again

forfeited any claim that the foundation for the officer’s testimony

regarding her HGN test results was insufficient. People v. Carter, 208

Ill. 2d 309, 318 (2003) (failure to include an issue in a petition for

leave to appeal results in forfeiture of that issue for review).

The State is correct that an issue may be deemed forfeited if a

petitioner fails to raise it in his petition for leave to appeal. However,

as we explained in In re Rolandis G., 232 Ill. 2d 13, 37 (2008), “the

failure to raise an issue in a petition for leave to appeal is not a

jurisdictional bar to this court’s ability to review a matter.”

Whether to review a forfeited issue under these circumstances is

within this court’s discretion. Rolandis G., 232 Ill. 2d at 37. We have

established a clear framework for the exercise of such discretion.

When an issue is not specifically mentioned in a party’s petition for

leave to appeal, but it is “ ‘inextricably intertwined’ ” with other

matters properly before the court, review is appropriate. Rolandis G.,

232 Ill. 2d at 37, quoting Hansen v. Baxter Healthcare Corp., 198 Ill.

2d 420, 430 (2002). If, however, the forfeited issue is not inextricably

intertwined with the issues properly before the court, the forfeiture

rule should be given effect.

The issues properly before this court in the present appeal are

whether, in general, evidence regarding HGN testing of a defendant

in a DUI prosecution is admissible under the Frye test and, if so, what

circumstances must be present before such evidence may be admitted

in a specific case. We conclude that the forfeited question is

inextricably intertwined with the issues that we have addressed herein,

-24-

particularly given the clear record Klatt’s testimony did not meet the

standards we have now adopted.

Admission of Klatt’s testimony regarding the HGN test he

performed in the absence of a proper foundation was error. Error will

be deemed harmless and a new trial unnecessary when “the competent

evidence in the record establishes the defendant’s guilt beyond a

reasonable doubt and it can be concluded that retrial without the

erroneous admission of the challenged evidence would produce no

different result.” People v. Arman, 131 Ill. 2d 115, 124 (1989).

In McKown I, we rejected the State’s argument that if denial of a

Frye hearing was error, it was harmless error. “Given the fact[s] that

defendant’s blood-alcohol content was not verified by any chemical

test, and no other field-sobriety tests were given,” we found it

“reasonable to conclude that the trial court relied heavily on the

improperly admitted HGN test results.” McKown I, 226 Ill. 2d at 276.

In light of our earlier decision, defendant’s conviction must be

reversed.

We must now consider whether a new trial would subject

defendant to double jeopardy. See People v. Jones, 175 Ill. 2d 126,

134 (1997); People v. McDonald, 125 Ill. 2d 182, 201 (1988). If the

evidence presented at the first trial, including the improperly admitted

evidence, would have been sufficient for any rational trier of fact to

find the essential elements of the crime proven beyond a reasonable

doubt, retrial is the proper remedy. People v. Lopez, 229 Ill. 2d 322,

367 (2008). If no rational trier of fact could so find, defendant may

not be subjected to a second trial.

In her brief, defendant argues that because the results of her HGN

test should not have been admitted into evidence, Klatt’s opinion,

which was based in part on the test results, should also be excluded

and that remand for a new trial would, therefore, violate double

jeopardy. She offers no authority for the proposition that an opinion

witness who is barred from testifying regarding one fact that entered

into the formation of his opinion is barred from giving an opinion

altogether. Further, she offers no authority for the proposition that a

police officer cannot testify to the facts and circumstances he observed

while investigating an accident.

We agree with the State that a new trial is proper. There is no bar

-25-

to the officer’s testifying regarding the facts and circumstances he

observed while investigating the accident. In addition, the officer’s

opinion regarding defendant’s state of intoxication was supported by

other facts in the record, aside from her performance on the HGN test.

Klatt testified that defendant had already been transported from

the scene when he arrived. He found a partially full can of beer in her

car. He spoke to defendant later at the hospital and observed that her

speech was slurred, her eyes were bloodshot, and she had a strong

odor of beer on her breath. Although she initially denied drinking that

day, she later admitted to him that she had consumed two cans of beer

before leaving her house, another can while driving, and had opened

a fourth can just prior to the accident. She also stated that she had

slept only four hours the previous night. At that point, Klatt

performed the HGN test. Because defendant was seated in a hospital

bed, he was unable to perform other field-sobriety tests.

There was sufficient information in Klatt’s possession prior to his

conducting the HGN test to allow him to form an opinion regarding

defendant’s impairment due to alcohol. At the time he interviewed

defendant, he already suspected her of driving under the influence

based on the statements of the other witnesses and the open can of

beer he found in her car. Her speech, eyes, and breath confirmed his

suspicion. Her admission that she had consumed three cans of beer

and was in the process of consuming a fourth can, after having only

four hours of sleep, provided further confirmation. The result of the

HGN test he performed may have merely provided additional support

for his opinion. We conclude that Klatt may testify regarding these

other facts and to the opinion he formed based on these facts. 4

In addition, three witnesses other than the officer testified

regarding the accident. Randall Retherford, another motorist, testified

that he drove his truck onto the shoulder of the road to avoid the

defendant’s car, which was approaching him at high speed. He saw

4

We note also that while the admission of the HGN test results in this case

was error, it was error because the State did not lay the proper foundation,

not because HGN test results are inadmissible in general. Thus, if the State

can lay the proper foundation for Klatt’s testimony on remand, the test

results will be admissible.

-26-

the defendant’s vehicle “lock up its wheels, veer to the left,” and hit

three on-coming motorcycles.

His testimony was corroborated by one of the injured riders,

Robert Stanley, who testified that as he lay on the ground after being

thrown from his motorcycle, defendant approached him and offered

to help him remove his helmet. He testified that he smelled the odor

of beer on her breath.

Another cyclist who was not involved in the accident, Chad

Morris, testified that he heard squealing tires and saw defendant’s car

veering into his lane, sliding sideways into the oncoming motorcycles.

He was able to stop in time to avoid being hit.

Viewing the testimony of these witnesses, in combination with the

admissible portion of Officer Klatt’s testimony, in the light most

favorable to the prosecution (see People v. Diggins, 235 Ill. 2d 48, 58

(1999)), there was sufficient evidence from which the trial court could

have found defendant guilty of aggravated driving under the influence

of alcohol beyond a reasonable doubt and, thus, double jeopardy does

not preclude a new trial. See People v. Hope, 116 Ill. 2d 265, 279

(1986). However, we note that nothing in this opinion should be

construed as a finding regarding defendant’s guilt that would be

binding upon remand.

Defendant argued in McKown I that the odor of alcohol on her

breath merely indicated that she had consumed alcohol, not that she

was impaired. She also argued that her bloodshot eyes could be

explained by her recent overnight shift working in a chemical plant.

These are arguments better addressed to the trier of fact. She is free

to make these arguments at her new trial.

CONCLUSION

In sum, we adopt the trial court’s findings on remand that HGN

testing is generally accepted in the relevant scientific fields as evidence

of alcohol consumption and possible impairment. We also adopt the

trial court’s five conclusions of law regarding the admission of HGN

evidence and its use at trial. The admissibility of HGN evidence in an

individual case will depend on the State’s ability to lay a proper

foundation and to demonstrate the qualifications of its witness, subject

to the balancing of probative value with the risk of unfair prejudice.

-27-

We find that admission of the officer’s testimony regarding HGN

testing in this case was reversible error. Thus, we reverse the

judgments of the appellate and circuit courts and remand the cause to

the circuit court for a new trial.

Judgments reversed;

cause remanded.

-28-