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Limiting The Use Of Hgn In Georgia Dui Refusal Cases

In Georgia DUI cases, the HGN test (sometimes called the “eye test”) can be one of the primary pieces of evidence that the state relies upon.  One of the primary areas of cross-examination that I focus upon with regard to the HGN test is the lack of correlation between the HGN test and a person’s actual driving ability.  However, this is frequently addressed by the state by questioning an officer about the correlation between the HGN test and a suspect’s BAC, and many will attempt to ask the officer if he has observed a correlation between the results on the HGN test subjects that did submit to the breath test in his cases.  Below is a motion that you can use to limit this type of testimony by an officer:


Comes Now, the Defendant in the above-styled case, by and through the undersigned counsel of record, and respectfully moves this Honorable Court to limit the arresting officer’s testimony regarding the horizontal gaze nystagmus (HGN) and breath test results in other cases.  In support of his motion, the Defendant shows this Honorable Court the following:

The Defendant was arrested on July 28, 2007 by XXXXXXXX of the XXXXXXXX.  In connection with his investigation of the Defendant, XXXXXXXXX performed the HGN test upon the Defendant.  The Defendant requests that the Trooper be precluded from offering any testimony regarding any alleged correlation between observations during the HGN test and breath tests results obtained in other cases.

The determination of whether a scientific principle or technique is admissible in criminal case in Georgia is governed by the rule stated in Harper v. State, 249 Ga. 519, 525-26, 292 S.E.2d 389 (1982).  The Harper rule requires that the Court in a criminal case determine “whether a given scientific principle or technique is a phenomenon that may be verified with such certainty that it is competent evidence in a court of law….”  Id. at 525.  Otherwise stated, the Court must determine whether the scientific principle or technique “has reached a scientific stage of verifiable certainty” or “‘rests upon the laws of nature.’”  Id. (citations omitted).  “[E]vidence based on a scientific principle or technique is admissible only if the science underlying the evidence is a phenomenon that may be verified with such certainty that it is competent evidence in a court of law.”  Parker v. State, 307 Ga.App. 61, 704 S.E.2d 438 (2010).

In Harper, the Georgia Supreme Court described the types of evidence that our trial courts should look to in determining whether a scientific principle or technique has reached a scientific stage of verifiable certainty.  The Harper court explicity expressed its disapproval of the “counting heads” rule of Frye v. United States, 293 F. 1013 (D.C. Cir. 1923).  Id.  According to the Harper Court:

The trial court may make this determination from evidence presented to it at trial by the parties; in this regard expert testimony may be of value. Or the trial court may base its determination on exhibits, treatises or the rationale of cases in other jurisdictions. The significant point is that the trial court makes this determination based on the evidence available to him rather than by simply calculating the consensus in the scientific community. Once a procedure has been recognized in a substantial number of courts, a trial judge may judicially notice, without receiving evidence, that the procedure has been established with verifiable certainty, or that it rests upon the laws of nature.

Id. at 525-26.  “[O]nce a procedure has been utilized for a significant period of time, and expert testimony has been received thereon in case after case, the trial court does not have to keep reinventing the wheel; a once novel technology can and does become commonplace.”  Hawkins v. State, 223 Ga. App. 34, 476 S.E.2d 803, 807 (1996).

Certain evaluations commonly employed in DUI investigations, such as the “ABCs,” the “Walk-and-Turn Test,” and the “One-Leg Stand Test,” have been recognized as “physical dexterity exercises that common sense, common experience, and the ‘laws of nature’” share are performed less well after drinking alcohol.”  Hawkins v. State, 223 Ga. App. 34, 476 S.E.2d 803, 807 (1996).  Accordingly, “[t]he screening of these gross motor skills is hardly the type of ‘scientific principle or technique’ to which Harper referred, and this Court will not hold these physical manifestations of impairment, which could be as obvious to the layperson as to the expert, to such a standard of admissibility.”  Id.

In contrast to those tests which test gross motor skills (e.g., a walk-and-turn or one-leg stand test) or which drawn upon commonsense for their utility in a DUI investigation (e.g., an alphabet test), certain tests typically employed in DUI investigations require a determination that the Harper standard has been satisfied.  In Hawkins, the Court of Appeals clarified that the horizontal gaze nystagmus (hereinafter, “HGN”) test is a scientific test that required a Harper foundation. The HGN test involves “the well-known and medically accepted principle that nystagmus can be caused by the ingestion of alcohol: ‘Jerk nystagmus … is characterized by a slow drift, usually away from the direction of gaze, followed by a quick jerk of recovery in the direction of gaze.  A motor disorder, it may be congenital or due to a variety of conditions affecting the brain, including ingestion of drugs such as alcohol and barbiturates….’”  Hawkins, 476 S.E.2d at 807 (citations omitted).

Any alleged correlation between HGN and a breath test result in other cases certainly does not rest upon “common sense, common experience, and the ‘laws of nature[.]’”  Hawkins, 476 S.E.2d at 807.  Any conclusion that there is an alleged correlation between HGN and a breath test result in other cases is a scientific conclusion and should be required to be scientifically accepted as having reached a “state of verifiable certainty in the scrientific community[.]”  Id. at 808.

In Hawkins, the Court further held that the “HGN test is an accepted, common procedure that has reached a state of verifiable certainty in the scrientific community and is admissible as a basis upon which an officer can determine that a driver was impaired by alcohol.”  Id. at 808.  Thus, the Hawkins Court held that the trial court was no longer required to hear expert testimony in order to introduce evidence of HGN.  Id.  In reaching its conclusion that the production of evidence to satisfy the Harper standard for admissibility was no longer required, the Court observed the following:

  1. the effect of alcohol on the eyes and inducing horizontal gaze nystagmus is recognized in The Merck Manual of Diagnosis and Therapy;
  2. the horizontal gaze nystagmus test has undergone validation studies sanctioned by the National Highway Traffic Safety Administration (Burns & Moskowitz, “Psychophysical Tests for DWI Arrest,” U.S. Department of Transportation, Rep. No. DOT-HS-802-424 (1977); Schweitz & Snyder, “Field Evaluation of a Behavioral Test Battery for DWI,” U.S. Department of Transportation, Rep. No. DOT-HS-806-475 (1983);
  3. the horizontal gaze nystagmus test has been employed by law enforcement in all 50 states;
  4. the relationship of horizontal gaze nystagmus to alcohol consumption was recognized in the premier DUI defense treatise (Erwin, Defense of Drunk Driving Cases (3rd ed. 1985), § 8.15A[3]);and
  5. “The characteristics, theory, and scientific acceptability of HGN testing in relation to DUI cases has been discussed in numerous articles and in numerous judicial opinions. See particularly, State v. Superior Court149 Ariz. 269, 718 P.2d 171, appendices A & B 182-184, 149 Ariz. 269, 718 P.2d 171 (1986); State v. Nagel, 30 Ohio App.3d 80, 506 N.E.2d 285 (1986); see also, e.g., Barnes, The Effects of Ethyl Alcohol on Visual Pursuit and Suppression of the Vestibulo-Ocular Reflex, 406 ACTA Otolaryngol Supp., p. 161 (Sweden 1984) (ethyl alcohol disrupted visual pursuit eye movement by increasing number of nystagmic “catch-up saccades”); Goldberg, Effects and After-Effects of Alcohol, Tranquilizers and Fatigue on Ocular Phenom- ena, Alcohol and Road Traffic, p. 123 (1963) (of different types of nystagmus, alcohol gaze nystagmus is the most easily observed); Zyo, Medico-Legal and Psychiatric Studies on the Alcoholic Intoxicated Offender, 30 Japanese J. of Legal Medicine, No. 3 (1976), p. 169 (recommends use of nystagmus test to determine somatic and mental symptoms of alcohol in- toxication, as well as blood alcohol content).”

Hawkins, 476 S.E.2d at 807-808.

While Hawkins acknowledged that HGN itself satisfies the Harper standard, there is no evidence that any attempt by the officer in this case to correlate between HGN and a breath test result in other cases  would satisy Harper as “a phenomenon that may be verified with such certainty that it is competent evidence in a court of law[.]”  Harper v. State, 249 Ga. at 525.  Accordingly, evidence regarding any alleged correlation between HGN and a breath test result in other cases should be excluded from the trial of this case until the State has adequately laid a foundation for the admission of such evidence in accordance with Harper.

Respectfully Submitted, this ___ day of ____________, 2012.

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About the Author

Ben Sessions, Attorney at Sessions Law Group
Ben Sessions

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