Though standard field sobriety tests (SFSTs) are widely administered by police officers across the nation, their scientific validity remains unproven and many factors could impede your performance on such exams.
First and foremost, it is important to realize that these tests cannot provide accurate readings for individuals who fall just above the legal limit.
The Walk and Turn Test
One of the standard field sobriety tests is the Walk and Turn test, designed to measure your ability to walk in a straight line heel-to-toe for nine steps, pivot, then return back to where you started from. According to NHTSA claims this can indicate DUI/DWI; however, its results can also be affected by external factors; medical conditions like back or inner ear problems could impede your performance on this test.
Officers must adhere to precise guidelines when administering DUI tests. A knowledgeable DUI lawyer may demonstrate that an unlawful test was administered, leaving its results dubious.
The One-Leg Stand Test
One of the most frequently administered field sobriety tests is the one-leg stand test. To perform this task, one foot should be raised six inches off of the ground while you count out loud in thousands (one thousand, two thousand, three thousand etc). Police officers look out for signs that suggest intoxication such as swaying while standing or placing one’s foot down; failing two or more clues provides probable cause to arrest someone for DUI.
Researchers have discovered that simply because a person fails a field sobriety test does not necessarily indicate they are drunk; sober individuals often perform poorly due to factors like age, physical limitations or weather conditions; our job as attorneys is to ensure these variables don’t allow officers to falsely accuse clients of DUI.
The Horizontal Gaze Nystagmus Test
Over 45 years of intensive studies, researchers have concluded that standard field sobriety tests (SFSTs), such as the Walk and Turn Test, One-Leg Stand Test, and Horizontal Gaze Nystagmus Test can accurately predict an individual’s blood alcohol concentration (BAC). Law enforcement officers must strictly abide by NHTSA’s SFST Student Manual in order to guarantee accurate results.
An officer administering a HGN test will place an object 12-15 inches from your nose and move it from side to side slowly, looking for any involuntary eye movement, known as nystagmus, that might occur as a response.
Cross examining officers who conduct HGN tests, our Atlanta DUI defense attorneys often point out that there is no conclusive proof connecting an eyeball nystagmus to driving safely – providing our clients an ideal opportunity to strengthen their defense against DUI charges.
The Breath Test
Police administering standard field sobriety tests (SFST) look for certain indicators of intoxication such as swaying, failing to follow instructions, and losing balance. Officers also often ask drivers to perform additional tasks such as reciting tongue twisters, saying partial ABCs or picking up coins with their fingers as part of these standardized exams.
Medical conditions and medications can impede your ability to complete these tests effectively. Vertigo can make it hard to walk in a straight line, leading to unsteadiness; similarly, ear infections, low blood pressure and eye muscle imbalance may impair performance as well.
Police may require you to blow into a portable breathalyzer as part of their sobriety test, measuring how much alcohol is present in your system and calculating your BAC, or blood alcohol concentration. While breathalyzers are capable of detecting alcohol consumption, they cannot tell what other substances might have entered your body, making their results less accurate than standard field sobriety tests results.
