Posted by duijim in on January 9, 2024
Law enforcement officers use several tests, known as standardized field sobriety tests, to ascertain whether a driver is impaired. These include horizontal gaze nystagmus test, 9 step walk and turn test and one leg stand test.
DUI investigations typically utilize tests with scientific backing for their investigations of DUI offenses, while officers will rely on general observations and portable breath testing as means for developing probable cause for arrest.
Horizontal Gaze Nystagmus Test
Horizontal Gaze Nystagmus (HGN) test is one of the standard field sobriety tests used by police officers to ascertain intoxication levels. It involves looking for involuntary eye jerking during eye movement that increases with alcohol or certain drugs consumption; and should provide law enforcement with enough probable cause to arrest you for DUI.
Deputy begins the test by having you fixate on a stationary stimulus – usually a penlight or other light placed 12-15 inches from your face and above eyebrow level – then moving it horizontally while watching for signs of nystagmus and tracking. They look for three specific clues: lack of smooth pursuit, distinct and sustained nystagmus at maximum deviation, and an initial appearance before 45 degrees as indicators that you are showing probable cause to arrest for DUI. If all three occur simultaneously then this would constitute positive test result and probable grounds to make an arrest charge against you based upon these three indicators alone if all three occur simultaneously then this test would result in probable cause to make an arrest for DUI arrest warrant.
Everyone has nystagmus, though it is typically undetectable by the naked eye. When drinking and driving, however, its prominence becomes more obvious, prompting law enforcement officers to use nystagmus as evidence of intoxication. Studies have proven the HGN test to be effective at identifying drunk drivers; however, other factors could impact its accuracy such as medical conditions or injuries, eye strain, fatigue and more.
To administer the HGN test, a suspect should remove their glasses or contact lenses before following a light for four seconds while keeping eyes open. When their eyes start jerking back and forth – known as the onset angle of nystagmus – this indicates an elevated blood alcohol concentration level.
There are two forms of nystagmus caused by drinking: alcohol gaze nystagmus and positional alcohol nystagmus, both detectable with the HGN and both can signal high BAC. But nystagmus may be caused by other things as well, including inner ear fluid movement, brain activity, eye muscle tension or neurological injuries or disease – as well as certain medications like antihistamines, sedatives or pain relievers.
The deputy will record each eye’s onset angle in the section labeled Medical Assessment on the front page, then check or uncheck equal pupil size, equal tracking, and resting nystagmus in their respective sections of the guide, recording any other facts, circumstances, conditions or observations made within that time. Finally, they will sign the page to certify compliance with NHTSA Manual requirements and administering test accordingly.
Walk and Turn Test
The walk and turn test, designed to measure balance and coordination, requires subjects to take nine steps heel-to-toe along a straight line before turning around and returning back the same way. An officer watches out for indicators like stepping off the line, using arms for balance or failing to walk heel-to-toe; these indicators could be indicators that someone has been drinking. Typically used with horizontal gaze nystagmus test and one leg stand test to ascertain driver impairment.
Problems with this test arise due to its demanding requirements of balance and coordination for success, making it particularly challenging for people with medical conditions that impede their balance to pass it. Furthermore, its results can also be affected by weather, road conditions and shoes worn; if two or more clues appear during this test officers assume their blood alcohol content (BAC) exceeds 0.08%.
For optimal accuracy, this test must be administered on hard, dry, even ground. Failing to meet this criteria could produce inaccurate results that have serious ramifications on a DUI case’s outcome.
Conducting this test can be extremely difficult for those who have trouble walking, poor vision, or other medical concerns; therefore it is wise to decline taking this test if pulled over for suspicion of DUI.
An experienced Georgia DUI attorney can challenge the results of a field sobriety test in several ways. They may review video footage showing how it was administered, searching for any discrepancies or irregularities. Furthermore, an attorney may hire an expert witness who provides testimony that calls into question its reliability or provides alternative explanations for suspect’s performance on test.
An Atlanta DUI lawyer could provide invaluable representation for drivers facing DUI charges in Georgia. An Atlanta DUI lawyer could assist them to challenge evidence obtained during field sobriety tests and fight their evidence successfully, possibly getting charges dismissed altogether. Contact them now to arrange a free consultation where an attorney from their firm will explain how these tests should function and discuss potential defense strategies and possible counterarguments; consultations are free and confidential and provide an ideal chance to ask any pertinent questions that you might have about your own situation. The firm accepts credit cards while also offering low flat fees that provide significant cost savings compared to litigation cases brought by competition.
One Leg Stand Test
The One Leg Stand Test is one of the many standardized field sobriety tests police officers use to gauge intoxication. It requires individuals to remain balanced for 30 seconds on one foot – an extremely challenging feat even under ideal conditions, let alone when standing alongside a road before an officer who might suspect they’re under the influence.
Beginning the test, an officer provides both verbal and visual instructions to their subject. Once in position, they instruct them to start. One foot must be raised approximately six inches off of the ground with its point facing forward while keeping their eyes focused on that raised foot while counting by thousands “one thousand one, two thousand two etc”. Until told otherwise by law enforcement.
Law enforcement officers are trained to recognize four signs of intoxication when administering this test, such as swaying while balancing, using arms for balance (moving more than six inches away from body), and maintaining one-legged stands.
An officer with proper training can distinguish these clues; however, even when administered accurately in an environment in which all relevant variables have been carefully considered and managed, accuracy typically only exceeds 65%. Furthermore, physical limitations, age, weight and footwear can all impact an individual’s ability to pass this test.
An experienced Atlanta DUI lawyers must challenge the results of this and other standardized field sobriety tests. An experienced lawyer may contend that these exams were improperly administered and affected by roadside distractions like uneven roads or gravel; glaring blue lights from patrol cars; or anxiety related to performing these supervised sobriety tests in front of police officers who believe you to be impaired.
Refusing field sobriety tests is your right, yet doing so could result in arrest if police officers cannot conduct breath or blood tests to measure your blood alcohol content. Get in touch with us now for a free consultation if arrested as a result of field sobriety test results; our legal team will fight hard for your freedom and rights in court should any arrest result; should a DUI conviction occur, we can also assist with driver’s license reinstatement process if needed. It is imperative that you understand your rights so you make wise choices regarding your future!