The outcomes of field sobriety tests such as coordination drills and horizontal gaze nystagmus can be affected by the presence of certain medical conditions in a driver. For example, Wisconsin drivers who suffer from medical nystagmus may fail HGN tests and may be charged with drunk driving when they were in fact not intoxicated while behind the wheels of their cars.
Nystagmus is a condition that affects the eyes. It can cause a person's eyes to move rapidly or unevenly in a variety of different directional patterns. Some individuals who are under the influence of alcohol temporarily adopt this condition and law enforcement officials look for it in field sobriety tests when assessing a person's potential level of drunkenness.
Problems during the development of a person's eyes can lead to nystagmus; individuals with ear and nervous system conditions can experience nystagmus at a higher rate than others. Even if a person does not have a diagnosed nystagmus condition the person may find the person's eyes behaving in such a way if the person is tired or under stress. Readers of this blog should recognize that the information provided is not offered as medical advice -- those who fear that they may suffer from nystagmus should seek out their own professional assessments.
However, drivers who have been charged with drunk driving and who suffer from medical nystagmus may find themselves facing difficult legal battles due to the mistakes made during their arrests. Such individuals should know that they have rights to offer evidence of their defenses during their drunk driving trials and may present their own stories with regard to the charges pending against them. Attorneys who work in the DUI defense field can help their clients prepare for their trials and present their medical conditions to the courts hearing their cases.