Wheaton, IL (PRWEB) April 7, 2010 -- In a sweeping decision, the Illinois Supreme Court placed limits on the police use of a sobriety test that had gone unchallenged in Illinois for the past 25 years. This case (People v. McKown (2010) --- N.E.2d ----, 2010 WL 572082 (Ill.) (McKown II) has been closely followed by police departments, prosecutors, and courts throughout the country, where similar challenges have been mounted against the test since it was first introduced by the National Highway Traffic Safety Administration in 1982.
The eye test known as horizontal gaze nystagmus or 'HGN', has been employed by police officers throughout the country since then, for determining whether someone was over the legal limit of 0.08. There are over 1.5 million drunk driving arrests every year in the United States, and virtually every police officer has used this test to determine whether a person was over 0.08 and hence 'under the influence'.
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
The Illinois Supreme Court ordered a special hearing involving national experts to determine the HGN test's scientific reliability and accuracy. The Illinois Supreme Court found that the eye test was improperly admitted into evidence, and threw out McKown's conviction. The Illinois Supreme Court barred the use of the test as proof that a driver was over .08 (the legal limit) and barring its use as anything more than a possibility of intoxication.
A similar challenge is currently underway in Kansas. HGN is one of three standardized field sobriety tests used in Georgia and Metro Atlanta DUIs. Many DUI police officers in the Atlanta area will testify that 4/6 clues on HGN equals impairment but this is not true and the test has only been validated for estimating probable blood alcohol at over .08 with 4/6 clues and over .1 with 6/6 clues with 77% accuracy. George C. Creal, Jr. has tried hundreds of cases where the HGN was attacked by using the Officer's training and training manuals against them to defeat them from using any improper inferences of impairment by the officer to the jury.