What Is A Horizontal Gaze Nystagmus Test?
What is the Horizontal Gaze Nystagmus Test?
Alcohol is a central nervous system depressant affecting many of the higher as well as lower motor control systems of the body. This results in poor motor coordination, sluggish reflexes, and emotional instability. The part of the nervous system that fine-tunes and controls hand movements and body posture also controls eye movements. When intoxicated, a person’s nervous system will display a breakdown in the smooth and accurate control of eye movements. This breakdown in the smooth control of eye movement may result in the inability to hold the eyes steady, resulting in a number of observable changes of impaired oculomotor functioning. See, Jack E. Richman & John Jakobowski, The Competency and Accuracy of Police Academy Recruits in the Use of the Horizontal Gaze Nystagmus Test for Detecting Alcohol Impairment, 47 New Eng. J. Optometry 5, 6 (Winter 1994). [Ed. Note, The citations and quotes in this DaytonDUI blog article were taken from HERE, HORIZONTAL GAZE NYSTAGMUS: THE SCIENCE & THE LAW, A Resource Guide for Judges, Prosecutors and Law Enforcement (no authorship or suggested citation given).
“Nystagmus” is a term used to describe a “bouncing” eye motion that is displayed in two ways: (1) pendular nystagmus, where the eye oscillates equally in two directions, and (2) jerk nystagmus, where the eye moves slowly away from a fixation point and then is rapidly corrected through a “saccadic” or fast movement. Raymond D. Adams & Maurice Victor, Principles of Neurology, ch.13, “Disorders of Ocular Movement and Pupillary Function,” 117 (4th ed. 1991). HGN is a type of jerk nystagmus with the saccadic movement toward the direction of the gaze. An eye normally moves smoothly like a marble rolling over a glass plane, whereas an eye with jerk nystagmus moves like a marble rolling across sandpaper. Most types of nystagmus, including HGN, are involuntary motions, meaning the person exhibiting the nystagmus cannot control it. C.J. Forkiotis, Optometric Exercise: The Scientific Basis for Alcohol Gaze Nystagmus, 59 Curriculum II, No. 7 at 9 (April 1987); Gregory W. Good & Arol R. Augsburger, Use of Horizontal Gaze Nystagmus as a Part of Roadside Sobriety Testing, 63 Am. J. of Optometry & Physiological Optics 467, 469 (1986). In fact, the subject exhibiting the nystagmus is unaware that it is happening because the bouncing of the eye does not affect the subject’s vision.
Alcohol causes two types: alcohol gaze nystagmus, which includes HGN, and positional alcohol nystagmus. Although alcohol causes both, alcohol gaze nystagmus and positional alcohol nystagmus are very different and easily distinguishable. Testing for positional alcohol nystagmus is not a part of the standardized field sobriety test battery. Defendants sometimes claim or attempt to confuse matters by arguing that the nystagmus the officer saw was actually positional alcohol nystagmus and not alcohol gaze nystagmus.
When an officer asks you to follow his pen, he is performing the horizontal gaze nystagmus test. Nystagmus is defined as the oscillation of the eyeball that occurs when there is a disturbance of the vestibular system or the oculomotor control of the eye. The nystagmus the officer is looking for is an involuntary motion. A person is usually unaware of the presence of a nystagmus and cannot control it. Forkiotis, C.J. Optometric Exercise: The Scientific Basis for Alcohol Gaze Nystagmus. 59 Curriculum II, No. 7 at 9 (April 1987); Good, Gregory W. & Augsburger, Arol R. Use of Horizontal Gaze Nystagmus as a Part of Roadside Sobriety Testing. 63 Am. J. of Optometry & Physiological Optics 467, 469 (1986); Stapleton, June M. et al. Effects of Alcohol and Other Psychotropic Drugs on Eye Movements: Relevance to Traffic Safety. 47 Q.J. Stud. on Alcohol 426, 430 (1986). The officer is looking for a type of nystagmus wherein the eye moves slowly in one direction and then returns rapidly, sometimes referred to as a jerk or jerking nystagmus. Adams, Raymond D. & Victor, Maurice. Disorders of Ocular Movement and Pupillary Function. Principles of Neurology. Ch.13, 117 (4th ed. 1991).
A major weakness in relying on the horizontal gaze nystagmus test in the criminal justice arena is that there are multiple causes of nystagmus that have been observed. Syndromes such as influenza, vertigo, epilepsy, measles, syphilis, arteriosclerosis, muscular dystrophy, multiple sclerosis, Korsakoff’s Syndrome, brain hemorrhage, streptococcus infections, and other psychogenic disorders all have been shown to produce nystagmus. Additionally, conditions such as hypertension, motion sickness, sunstroke, eyestrain, eye muscle fatigue, glaucoma, and changes in atmospheric pressure may result in gaze nystagmus. Pangman. Horizontal Gaze Nystagmus: Voodoo Science. 2 DWI J. 1, 3-4 (1987). Caffeine, nicotine and aspirin (alone or in combination with alcohol) can also lead to a nystagmus which mimics a nystagmus attributable to alcohol consumption. Id. at 3-4. Scientific literature also points to a person’s circadian rhythms or biorhythms as having an affect on nystagmus readings as the body reacts differently to alcohol at different times in the day and even fatigue nystagmus can be found in an individual, and the list, according to critics, goes on. Id. at 3-4; Booker, J.L. End-position nystagmus as an indicator of ethanol intoxication. Sci Justice. 41(2):113-116. (April – June, 2001).
The horizontal gaze nystagmus test is not present in marijuana impairment cases. In State v. Dixon, 2007-Ohio-5189 (Ohio Ct. App. 12th Dist. Clermont County 2007), the court addressed the issue of standardized field sobriety tests and marijuana impairment. Relying upon the NHTSA standards, the court concluded that observations as to performance on the walk & turn test and the one-leg stand test were indicative of impairment, thus allowing those to be used against a suspected marijuana user. The HGN test, however, is not indicative of marijuana impairment. According to NHTSA nystagmus would not be present due to marijuana and, as such, it was plain error to admit evidence of the horizontal gaze nystagmus test against the defendant accused of marijuana impairment.
Ohio Revised Code 4511.19(D)(4)(b) sets forth the standards for admissibility of the results of field sobriety tests in OVI (drunk driving) prosecutions. See State v. Bozcar, 113 Ohio St. 3d 148, 2007-Ohio-1251, 863 N.E.2d 115 (2007). In order for the tests to be admissible, the State must demonstrate:
- By clear and convincing evidence.
- The Officer administered the tests insubstantial compliance.
- The testing standards for any reliable, credible, and generally accepted test.
- Including, but not limited to, the standards set by NHTSA.
The only guidance provided for determining the meaning of “substantial compliance” has come from State v. Burnside, 100 Ohio St. 3d 152, 2003-Ohio-5372 (2003), wherein the court indicated that errors that are clearly “de minimus” or “minor procedural deviations” are not substantial. Thus, the State must set forth the testing standards, offer some testimony that the testing standards have been accepted and that the officer has substantially complied. If the State fails to introduce testimonial or documentary evidence of the standards (most likely via the NHTSA training manual), then they have not met this burden. See Village of Gates Mills v. Mace, 2005-Ohio-2191 (Ohio Ct. App. 8th Dist., Cuyahoga County), wherein the State did not meet this burden despite the Court having its own copy of the manual.
In my practice we have seen a trend to manipulating the “substantial compliance” standard into a de facto prejudice standard. The burden is being subtly shifted to the defendant to demonstrate that he or she was somehow prejudiced by the officer’s failure to comply with the NHTSA standards. For example; if the officer does not articulate that he advised the suspect not to raise his or her arms, the Court says that he substantially complied by merely mentioning that he was trained in NHTSA protocols. If, however, the defense points out that the officer did not give the proper instruction and still scored the test in a way negative to the defendant, the court may consider excluding some portion or all of the test. Case law can be helpful on this point.
In State v. Clay, 34 Ohio St. 2d 250, 298 N.E.2d 137 (1973) the court ruled, “[h]owever, if by cross examination or otherwise, the defense places such compliance at issue, it then is incumbent upon the State, in order to maintain its burden of proof, to offer the methods and regulations into evidence and prove compliance.” Some courts may try to take Judicial Notice of the manual (See Evid. R 201) when no manual was introduced. In State v. Wells 2005-Ohio-5008 (Ohio Ct. App. 2d Dist., Montgomery County) held that the court cannot assume judicial notice when the record does not demonstrate a request for judicial notice or a reference to the manual by the trial court. The 9th District Court of Appeals issued a great decision on the issue of substantial compliance. Specifically, the issue involved giving the HGN test while the Defendant was seated in the car. The Court found that this was not substantial compliance. (State v. Haneberg 5/29/2007, 2007-Ohio-2561, 9th District Court of Appeals).
The validity of Standardized Field Sobriety Tests results is dependent upon law enforcement practitioners following the established, standardized procedures for test administration and scoring. NHTSA’s SFST Student Manual states that the procedures demonstrated in the training program describe how SFSTs should be administered under ideal conditions, but that ideal conditions do not always exist in the field. Variations from ideal conditions, and deviations from the standardized procedures, might affect the evidentiary weight that should be given to test results.
Attorney Charles M. Rowland II dedicates his practice to defending the accused drunk driver in the Miami Valley and throughout Ohio. He has the credentials and the experience to win your case and has made himself Dayton’s choice for drunk driving defense. Contact Charles Rowland by phone at (937) 318-1384 or toll-free at 1-888-ROWLAND (888-769-5263). If you need assistance after hours, call the 24/7 DUI Hotline at (937) 776-2671. You can have DaytonDUI at your fingertips by downloading the DaytonDUI Android App or have DaytonDUI sent directly to your mobile device by texting DaytonDUI (one word) to 50500. Follow DaytonDUI on Facebook, @DaytonDUI on Twitter, YouTube, Tumblr, Pheed and Pintrest or get RSS of the Ohio DUI blog. “All I do is DUI defense.”
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